nextcloud / server

lib/private/Files/View.php

Indentation +2090 added lines, -2090 removed lines

@@ -83,2094 +83,2094 @@
  * \OC\Files\Storage\Storage object
  */
 class View {
-	/** @var string */
-	private $fakeRoot = '';
-
-	/**
-	 * @var \OCP\Lock\ILockingProvider
-	 */
-	protected $lockingProvider;
-
-	private $lockingEnabled;
-
-	private $updaterEnabled = true;
-
-	/** @var \OC\User\Manager */
-	private $userManager;
-
-	/** @var \OCP\ILogger */
-	private $logger;
-
-	/**
-	 * @param string $root
-	 * @throws \Exception If $root contains an invalid path
-	 */
-	public function __construct($root = '') {
-		if (is_null($root)) {
-			throw new \InvalidArgumentException('Root can\'t be null');
-		}
-		if (!Filesystem::isValidPath($root)) {
-			throw new \Exception();
-		}
-
-		$this->fakeRoot = $root;
-		$this->lockingProvider = \OC::$server->getLockingProvider();
-		$this->lockingEnabled = !($this->lockingProvider instanceof \OC\Lock\NoopLockingProvider);
-		$this->userManager = \OC::$server->getUserManager();
-		$this->logger = \OC::$server->getLogger();
-	}
-
-	public function getAbsolutePath($path = '/') {
-		if ($path === null) {
-			return null;
-		}
-		$this->assertPathLength($path);
-		if ($path === '') {
-			$path = '/';
-		}
-		if ($path[0] !== '/') {
-			$path = '/' . $path;
-		}
-		return $this->fakeRoot . $path;
-	}
-
-	/**
-	 * change the root to a fake root
-	 *
-	 * @param string $fakeRoot
-	 * @return boolean|null
-	 */
-	public function chroot($fakeRoot) {
-		if (!$fakeRoot == '') {
-			if ($fakeRoot[0] !== '/') {
-				$fakeRoot = '/' . $fakeRoot;
-			}
-		}
-		$this->fakeRoot = $fakeRoot;
-	}
-
-	/**
-	 * get the fake root
-	 *
-	 * @return string
-	 */
-	public function getRoot() {
-		return $this->fakeRoot;
-	}
-
-	/**
-	 * get path relative to the root of the view
-	 *
-	 * @param string $path
-	 * @return string
-	 */
-	public function getRelativePath($path) {
-		$this->assertPathLength($path);
-		if ($this->fakeRoot == '') {
-			return $path;
-		}
-
-		if (rtrim($path, '/') === rtrim($this->fakeRoot, '/')) {
-			return '/';
-		}
-
-		// missing slashes can cause wrong matches!
-		$root = rtrim($this->fakeRoot, '/') . '/';
-
-		if (strpos($path, $root) !== 0) {
-			return null;
-		} else {
-			$path = substr($path, strlen($this->fakeRoot));
-			if (strlen($path) === 0) {
-				return '/';
-			} else {
-				return $path;
-			}
-		}
-	}
-
-	/**
-	 * get the mountpoint of the storage object for a path
-	 * ( note: because a storage is not always mounted inside the fakeroot, the
-	 * returned mountpoint is relative to the absolute root of the filesystem
-	 * and does not take the chroot into account )
-	 *
-	 * @param string $path
-	 * @return string
-	 */
-	public function getMountPoint($path) {
-		return Filesystem::getMountPoint($this->getAbsolutePath($path));
-	}
-
-	/**
-	 * get the mountpoint of the storage object for a path
-	 * ( note: because a storage is not always mounted inside the fakeroot, the
-	 * returned mountpoint is relative to the absolute root of the filesystem
-	 * and does not take the chroot into account )
-	 *
-	 * @param string $path
-	 * @return \OCP\Files\Mount\IMountPoint
-	 */
-	public function getMount($path) {
-		return Filesystem::getMountManager()->find($this->getAbsolutePath($path));
-	}
-
-	/**
-	 * resolve a path to a storage and internal path
-	 *
-	 * @param string $path
-	 * @return array an array consisting of the storage and the internal path
-	 */
-	public function resolvePath($path) {
-		$a = $this->getAbsolutePath($path);
-		$p = Filesystem::normalizePath($a);
-		return Filesystem::resolvePath($p);
-	}
-
-	/**
-	 * return the path to a local version of the file
-	 * we need this because we can't know if a file is stored local or not from
-	 * outside the filestorage and for some purposes a local file is needed
-	 *
-	 * @param string $path
-	 * @return string
-	 */
-	public function getLocalFile($path) {
-		$parent = substr($path, 0, strrpos($path, '/'));
-		$path = $this->getAbsolutePath($path);
-		list($storage, $internalPath) = Filesystem::resolvePath($path);
-		if (Filesystem::isValidPath($parent) and $storage) {
-			return $storage->getLocalFile($internalPath);
-		} else {
-			return null;
-		}
-	}
-
-	/**
-	 * @param string $path
-	 * @return string
-	 */
-	public function getLocalFolder($path) {
-		$parent = substr($path, 0, strrpos($path, '/'));
-		$path = $this->getAbsolutePath($path);
-		list($storage, $internalPath) = Filesystem::resolvePath($path);
-		if (Filesystem::isValidPath($parent) and $storage) {
-			return $storage->getLocalFolder($internalPath);
-		} else {
-			return null;
-		}
-	}
-
-	/**
-	 * the following functions operate with arguments and return values identical
-	 * to those of their PHP built-in equivalents. Mostly they are merely wrappers
-	 * for \OC\Files\Storage\Storage via basicOperation().
-	 */
-	public function mkdir($path) {
-		return $this->basicOperation('mkdir', $path, array('create', 'write'));
-	}
-
-	/**
-	 * remove mount point
-	 *
-	 * @param \OC\Files\Mount\MoveableMount $mount
-	 * @param string $path relative to data/
-	 * @return boolean
-	 */
-	protected function removeMount($mount, $path) {
-		if ($mount instanceof MoveableMount) {
-			// cut of /user/files to get the relative path to data/user/files
-			$pathParts = explode('/', $path, 4);
-			$relPath = '/' . $pathParts[3];
-			$this->lockFile($relPath, ILockingProvider::LOCK_SHARED, true);
-			\OC_Hook::emit(
-				Filesystem::CLASSNAME, "umount",
-				array(Filesystem::signal_param_path => $relPath)
-			);
-			$this->changeLock($relPath, ILockingProvider::LOCK_EXCLUSIVE, true);
-			$result = $mount->removeMount();
-			$this->changeLock($relPath, ILockingProvider::LOCK_SHARED, true);
-			if ($result) {
-				\OC_Hook::emit(
-					Filesystem::CLASSNAME, "post_umount",
-					array(Filesystem::signal_param_path => $relPath)
-				);
-			}
-			$this->unlockFile($relPath, ILockingProvider::LOCK_SHARED, true);
-			return $result;
-		} else {
-			// do not allow deleting the storage's root / the mount point
-			// because for some storages it might delete the whole contents
-			// but isn't supposed to work that way
-			return false;
-		}
-	}
-
-	public function disableCacheUpdate() {
-		$this->updaterEnabled = false;
-	}
-
-	public function enableCacheUpdate() {
-		$this->updaterEnabled = true;
-	}
-
-	protected function writeUpdate(Storage $storage, $internalPath, $time = null) {
-		if ($this->updaterEnabled) {
-			if (is_null($time)) {
-				$time = time();
-			}
-			$storage->getUpdater()->update($internalPath, $time);
-		}
-	}
-
-	protected function removeUpdate(Storage $storage, $internalPath) {
-		if ($this->updaterEnabled) {
-			$storage->getUpdater()->remove($internalPath);
-		}
-	}
-
-	protected function renameUpdate(Storage $sourceStorage, Storage $targetStorage, $sourceInternalPath, $targetInternalPath) {
-		if ($this->updaterEnabled) {
-			$targetStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
-		}
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function rmdir($path) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$mount = Filesystem::getMountManager()->find($absolutePath);
-		if ($mount->getInternalPath($absolutePath) === '') {
-			return $this->removeMount($mount, $absolutePath);
-		}
-		if ($this->is_dir($path)) {
-			$result = $this->basicOperation('rmdir', $path, array('delete'));
-		} else {
-			$result = false;
-		}
-
-		if (!$result && !$this->file_exists($path)) { //clear ghost files from the cache on delete
-			$storage = $mount->getStorage();
-			$internalPath = $mount->getInternalPath($absolutePath);
-			$storage->getUpdater()->remove($internalPath);
-		}
-		return $result;
-	}
-
-	/**
-	 * @param string $path
-	 * @return resource
-	 */
-	public function opendir($path) {
-		return $this->basicOperation('opendir', $path, array('read'));
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function is_dir($path) {
-		if ($path == '/') {
-			return true;
-		}
-		return $this->basicOperation('is_dir', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function is_file($path) {
-		if ($path == '/') {
-			return false;
-		}
-		return $this->basicOperation('is_file', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function stat($path) {
-		return $this->basicOperation('stat', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function filetype($path) {
-		return $this->basicOperation('filetype', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function filesize($path) {
-		return $this->basicOperation('filesize', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 * @throws \OCP\Files\InvalidPathException
-	 */
-	public function readfile($path) {
-		$this->assertPathLength($path);
-		@ob_end_clean();
-		$handle = $this->fopen($path, 'rb');
-		if ($handle) {
-			$chunkSize = 8192; // 8 kB chunks
-			while (!feof($handle)) {
-				echo fread($handle, $chunkSize);
-				flush();
-			}
-			fclose($handle);
-			return $this->filesize($path);
-		}
-		return false;
-	}
-
-	/**
-	 * @param string $path
-	 * @param int $from
-	 * @param int $to
-	 * @return bool|mixed
-	 * @throws \OCP\Files\InvalidPathException
-	 * @throws \OCP\Files\UnseekableException
-	 */
-	public function readfilePart($path, $from, $to) {
-		$this->assertPathLength($path);
-		@ob_end_clean();
-		$handle = $this->fopen($path, 'rb');
-		if ($handle) {
-			$chunkSize = 8192; // 8 kB chunks
-			$startReading = true;
-
-			if ($from !== 0 && $from !== '0' && fseek($handle, $from) !== 0) {
-				// forward file handle via chunked fread because fseek seem to have failed
-
-				$end = $from + 1;
-				while (!feof($handle) && ftell($handle) < $end) {
-					$len = $from - ftell($handle);
-					if ($len > $chunkSize) {
-						$len = $chunkSize;
-					}
-					$result = fread($handle, $len);
-
-					if ($result === false) {
-						$startReading = false;
-						break;
-					}
-				}
-			}
-
-			if ($startReading) {
-				$end = $to + 1;
-				while (!feof($handle) && ftell($handle) < $end) {
-					$len = $end - ftell($handle);
-					if ($len > $chunkSize) {
-						$len = $chunkSize;
-					}
-					echo fread($handle, $len);
-					flush();
-				}
-				return ftell($handle) - $from;
-			}
-
-			throw new \OCP\Files\UnseekableException('fseek error');
-		}
-		return false;
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function isCreatable($path) {
-		return $this->basicOperation('isCreatable', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function isReadable($path) {
-		return $this->basicOperation('isReadable', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function isUpdatable($path) {
-		return $this->basicOperation('isUpdatable', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function isDeletable($path) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$mount = Filesystem::getMountManager()->find($absolutePath);
-		if ($mount->getInternalPath($absolutePath) === '') {
-			return $mount instanceof MoveableMount;
-		}
-		return $this->basicOperation('isDeletable', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function isSharable($path) {
-		return $this->basicOperation('isSharable', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function file_exists($path) {
-		if ($path == '/') {
-			return true;
-		}
-		return $this->basicOperation('file_exists', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function filemtime($path) {
-		return $this->basicOperation('filemtime', $path);
-	}
-
-	/**
-	 * @param string $path
-	 * @param int|string $mtime
-	 * @return bool
-	 */
-	public function touch($path, $mtime = null) {
-		if (!is_null($mtime) and !is_numeric($mtime)) {
-			$mtime = strtotime($mtime);
-		}
-
-		$hooks = array('touch');
-
-		if (!$this->file_exists($path)) {
-			$hooks[] = 'create';
-			$hooks[] = 'write';
-		}
-		$result = $this->basicOperation('touch', $path, $hooks, $mtime);
-		if (!$result) {
-			// If create file fails because of permissions on external storage like SMB folders,
-			// check file exists and return false if not.
-			if (!$this->file_exists($path)) {
-				return false;
-			}
-			if (is_null($mtime)) {
-				$mtime = time();
-			}
-			//if native touch fails, we emulate it by changing the mtime in the cache
-			$this->putFileInfo($path, array('mtime' => floor($mtime)));
-		}
-		return true;
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 */
-	public function file_get_contents($path) {
-		return $this->basicOperation('file_get_contents', $path, array('read'));
-	}
-
-	/**
-	 * @param bool $exists
-	 * @param string $path
-	 * @param bool $run
-	 */
-	protected function emit_file_hooks_pre($exists, $path, &$run) {
-		if (!$exists) {
-			\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_create, array(
-				Filesystem::signal_param_path => $this->getHookPath($path),
-				Filesystem::signal_param_run => &$run,
-			));
-		} else {
-			\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_update, array(
-				Filesystem::signal_param_path => $this->getHookPath($path),
-				Filesystem::signal_param_run => &$run,
-			));
-		}
-		\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_write, array(
-			Filesystem::signal_param_path => $this->getHookPath($path),
-			Filesystem::signal_param_run => &$run,
-		));
-	}
-
-	/**
-	 * @param bool $exists
-	 * @param string $path
-	 */
-	protected function emit_file_hooks_post($exists, $path) {
-		if (!$exists) {
-			\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_create, array(
-				Filesystem::signal_param_path => $this->getHookPath($path),
-			));
-		} else {
-			\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_update, array(
-				Filesystem::signal_param_path => $this->getHookPath($path),
-			));
-		}
-		\OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_write, array(
-			Filesystem::signal_param_path => $this->getHookPath($path),
-		));
-	}
-
-	/**
-	 * @param string $path
-	 * @param string|resource $data
-	 * @return bool|mixed
-	 * @throws \Exception
-	 */
-	public function file_put_contents($path, $data) {
-		if (is_resource($data)) { //not having to deal with streams in file_put_contents makes life easier
-			$absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
-			if (Filesystem::isValidPath($path)
-				and !Filesystem::isFileBlacklisted($path)
-			) {
-				$path = $this->getRelativePath($absolutePath);
-
-				$this->lockFile($path, ILockingProvider::LOCK_SHARED);
-
-				$exists = $this->file_exists($path);
-				$run = true;
-				if ($this->shouldEmitHooks($path)) {
-					$this->emit_file_hooks_pre($exists, $path, $run);
-				}
-				if (!$run) {
-					$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-					return false;
-				}
-
-				$this->changeLock($path, ILockingProvider::LOCK_EXCLUSIVE);
-
-				/** @var \OC\Files\Storage\Storage $storage */
-				list($storage, $internalPath) = $this->resolvePath($path);
-				$target = $storage->fopen($internalPath, 'w');
-				if ($target) {
-					list (, $result) = \OC_Helper::streamCopy($data, $target);
-					fclose($target);
-					fclose($data);
-
-					$this->writeUpdate($storage, $internalPath);
-
-					$this->changeLock($path, ILockingProvider::LOCK_SHARED);
-
-					if ($this->shouldEmitHooks($path) && $result !== false) {
-						$this->emit_file_hooks_post($exists, $path);
-					}
-					$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-					return $result;
-				} else {
-					$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
-					return false;
-				}
-			} else {
-				return false;
-			}
-		} else {
-			$hooks = $this->file_exists($path) ? array('update', 'write') : array('create', 'write');
-			return $this->basicOperation('file_put_contents', $path, $hooks, $data);
-		}
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|mixed
-	 */
-	public function unlink($path) {
-		if ($path === '' || $path === '/') {
-			// do not allow deleting the root
-			return false;
-		}
-		$postFix = (substr($path, -1) === '/') ? '/' : '';
-		$absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
-		$mount = Filesystem::getMountManager()->find($absolutePath . $postFix);
-		if ($mount and $mount->getInternalPath($absolutePath) === '') {
-			return $this->removeMount($mount, $absolutePath);
-		}
-		if ($this->is_dir($path)) {
-			$result = $this->basicOperation('rmdir', $path, ['delete']);
-		} else {
-			$result = $this->basicOperation('unlink', $path, ['delete']);
-		}
-		if (!$result && !$this->file_exists($path)) { //clear ghost files from the cache on delete
-			$storage = $mount->getStorage();
-			$internalPath = $mount->getInternalPath($absolutePath);
-			$storage->getUpdater()->remove($internalPath);
-			return true;
-		} else {
-			return $result;
-		}
-	}
-
-	/**
-	 * @param string $directory
-	 * @return bool|mixed
-	 */
-	public function deleteAll($directory) {
-		return $this->rmdir($directory);
-	}
-
-	/**
-	 * Rename/move a file or folder from the source path to target path.
-	 *
-	 * @param string $path1 source path
-	 * @param string $path2 target path
-	 *
-	 * @return bool|mixed
-	 */
-	public function rename($path1, $path2) {
-		$absolutePath1 = Filesystem::normalizePath($this->getAbsolutePath($path1));
-		$absolutePath2 = Filesystem::normalizePath($this->getAbsolutePath($path2));
-		$result = false;
-		if (
-			Filesystem::isValidPath($path2)
-			and Filesystem::isValidPath($path1)
-			and !Filesystem::isFileBlacklisted($path2)
-		) {
-			$path1 = $this->getRelativePath($absolutePath1);
-			$path2 = $this->getRelativePath($absolutePath2);
-			$exists = $this->file_exists($path2);
-
-			if ($path1 == null or $path2 == null) {
-				return false;
-			}
-
-			$this->lockFile($path1, ILockingProvider::LOCK_SHARED, true);
-			try {
-				$this->lockFile($path2, ILockingProvider::LOCK_SHARED, true);
-
-				$run = true;
-				if ($this->shouldEmitHooks($path1) && (Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2))) {
-					// if it was a rename from a part file to a regular file it was a write and not a rename operation
-					$this->emit_file_hooks_pre($exists, $path2, $run);
-				} elseif ($this->shouldEmitHooks($path1)) {
-					\OC_Hook::emit(
-						Filesystem::CLASSNAME, Filesystem::signal_rename,
-						array(
-							Filesystem::signal_param_oldpath => $this->getHookPath($path1),
-							Filesystem::signal_param_newpath => $this->getHookPath($path2),
-							Filesystem::signal_param_run => &$run
-						)
-					);
-				}
-				if ($run) {
-					$this->verifyPath(dirname($path2), basename($path2));
-
-					$manager = Filesystem::getMountManager();
-					$mount1 = $this->getMount($path1);
-					$mount2 = $this->getMount($path2);
-					$storage1 = $mount1->getStorage();
-					$storage2 = $mount2->getStorage();
-					$internalPath1 = $mount1->getInternalPath($absolutePath1);
-					$internalPath2 = $mount2->getInternalPath($absolutePath2);
-
-					$this->changeLock($path1, ILockingProvider::LOCK_EXCLUSIVE, true);
-					try {
-						$this->changeLock($path2, ILockingProvider::LOCK_EXCLUSIVE, true);
-
-						if ($internalPath1 === '') {
-							if ($mount1 instanceof MoveableMount) {
-								$sourceParentMount = $this->getMount(dirname($path1));
-								if ($sourceParentMount === $mount2 && $this->targetIsNotShared($storage2, $internalPath2)) {
-									/**
-									 * @var \OC\Files\Mount\MountPoint | \OC\Files\Mount\MoveableMount $mount1
-									 */
-									$sourceMountPoint = $mount1->getMountPoint();
-									$result = $mount1->moveMount($absolutePath2);
-									$manager->moveMount($sourceMountPoint, $mount1->getMountPoint());
-								} else {
-									$result = false;
-								}
-							} else {
-								$result = false;
-							}
-							// moving a file/folder within the same mount point
-						} elseif ($storage1 === $storage2) {
-							if ($storage1) {
-								$result = $storage1->rename($internalPath1, $internalPath2);
-							} else {
-								$result = false;
-							}
-							// moving a file/folder between storages (from $storage1 to $storage2)
-						} else {
-							$result = $storage2->moveFromStorage($storage1, $internalPath1, $internalPath2);
-						}
-
-						if ((Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2)) && $result !== false) {
-							// if it was a rename from a part file to a regular file it was a write and not a rename operation
-							$this->writeUpdate($storage2, $internalPath2);
-						} else if ($result) {
-							if ($internalPath1 !== '') { // don't do a cache update for moved mounts
-								$this->renameUpdate($storage1, $storage2, $internalPath1, $internalPath2);
-							}
-						}
-					} catch(\Exception $e) {
-						throw $e;
-					} finally {
-						$this->changeLock($path1, ILockingProvider::LOCK_SHARED, true);
-						$this->changeLock($path2, ILockingProvider::LOCK_SHARED, true);
-					}
-
-					if ((Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2)) && $result !== false) {
-						if ($this->shouldEmitHooks()) {
-							$this->emit_file_hooks_post($exists, $path2);
-						}
-					} elseif ($result) {
-						if ($this->shouldEmitHooks($path1) and $this->shouldEmitHooks($path2)) {
-							\OC_Hook::emit(
-								Filesystem::CLASSNAME,
-								Filesystem::signal_post_rename,
-								array(
-									Filesystem::signal_param_oldpath => $this->getHookPath($path1),
-									Filesystem::signal_param_newpath => $this->getHookPath($path2)
-								)
-							);
-						}
-					}
-				}
-			} catch(\Exception $e) {
-				throw $e;
-			} finally {
-				$this->unlockFile($path1, ILockingProvider::LOCK_SHARED, true);
-				$this->unlockFile($path2, ILockingProvider::LOCK_SHARED, true);
-			}
-		}
-		return $result;
-	}
-
-	/**
-	 * Copy a file/folder from the source path to target path
-	 *
-	 * @param string $path1 source path
-	 * @param string $path2 target path
-	 * @param bool $preserveMtime whether to preserve mtime on the copy
-	 *
-	 * @return bool|mixed
-	 */
-	public function copy($path1, $path2, $preserveMtime = false) {
-		$absolutePath1 = Filesystem::normalizePath($this->getAbsolutePath($path1));
-		$absolutePath2 = Filesystem::normalizePath($this->getAbsolutePath($path2));
-		$result = false;
-		if (
-			Filesystem::isValidPath($path2)
-			and Filesystem::isValidPath($path1)
-			and !Filesystem::isFileBlacklisted($path2)
-		) {
-			$path1 = $this->getRelativePath($absolutePath1);
-			$path2 = $this->getRelativePath($absolutePath2);
-
-			if ($path1 == null or $path2 == null) {
-				return false;
-			}
-			$run = true;
-
-			$this->lockFile($path2, ILockingProvider::LOCK_SHARED);
-			$this->lockFile($path1, ILockingProvider::LOCK_SHARED);
-			$lockTypePath1 = ILockingProvider::LOCK_SHARED;
-			$lockTypePath2 = ILockingProvider::LOCK_SHARED;
-
-			try {
-
-				$exists = $this->file_exists($path2);
-				if ($this->shouldEmitHooks()) {
-					\OC_Hook::emit(
-						Filesystem::CLASSNAME,
-						Filesystem::signal_copy,
-						array(
-							Filesystem::signal_param_oldpath => $this->getHookPath($path1),
-							Filesystem::signal_param_newpath => $this->getHookPath($path2),
-							Filesystem::signal_param_run => &$run
-						)
-					);
-					$this->emit_file_hooks_pre($exists, $path2, $run);
-				}
-				if ($run) {
-					$mount1 = $this->getMount($path1);
-					$mount2 = $this->getMount($path2);
-					$storage1 = $mount1->getStorage();
-					$internalPath1 = $mount1->getInternalPath($absolutePath1);
-					$storage2 = $mount2->getStorage();
-					$internalPath2 = $mount2->getInternalPath($absolutePath2);
-
-					$this->changeLock($path2, ILockingProvider::LOCK_EXCLUSIVE);
-					$lockTypePath2 = ILockingProvider::LOCK_EXCLUSIVE;
-
-					if ($mount1->getMountPoint() == $mount2->getMountPoint()) {
-						if ($storage1) {
-							$result = $storage1->copy($internalPath1, $internalPath2);
-						} else {
-							$result = false;
-						}
-					} else {
-						$result = $storage2->copyFromStorage($storage1, $internalPath1, $internalPath2);
-					}
-
-					$this->writeUpdate($storage2, $internalPath2);
-
-					$this->changeLock($path2, ILockingProvider::LOCK_SHARED);
-					$lockTypePath2 = ILockingProvider::LOCK_SHARED;
-
-					if ($this->shouldEmitHooks() && $result !== false) {
-						\OC_Hook::emit(
-							Filesystem::CLASSNAME,
-							Filesystem::signal_post_copy,
-							array(
-								Filesystem::signal_param_oldpath => $this->getHookPath($path1),
-								Filesystem::signal_param_newpath => $this->getHookPath($path2)
-							)
-						);
-						$this->emit_file_hooks_post($exists, $path2);
-					}
-
-				}
-			} catch (\Exception $e) {
-				$this->unlockFile($path2, $lockTypePath2);
-				$this->unlockFile($path1, $lockTypePath1);
-				throw $e;
-			}
-
-			$this->unlockFile($path2, $lockTypePath2);
-			$this->unlockFile($path1, $lockTypePath1);
-
-		}
-		return $result;
-	}
-
-	/**
-	 * @param string $path
-	 * @param string $mode 'r' or 'w'
-	 * @return resource
-	 */
-	public function fopen($path, $mode) {
-		$mode = str_replace('b', '', $mode); // the binary flag is a windows only feature which we do not support
-		$hooks = array();
-		switch ($mode) {
-			case 'r':
-				$hooks[] = 'read';
-				break;
-			case 'r+':
-			case 'w+':
-			case 'x+':
-			case 'a+':
-				$hooks[] = 'read';
-				$hooks[] = 'write';
-				break;
-			case 'w':
-			case 'x':
-			case 'a':
-				$hooks[] = 'write';
-				break;
-			default:
-				\OCP\Util::writeLog('core', 'invalid mode (' . $mode . ') for ' . $path, ILogger::ERROR);
-		}
-
-		if ($mode !== 'r' && $mode !== 'w') {
-			\OC::$server->getLogger()->info('Trying to open a file with a mode other than "r" or "w" can cause severe performance issues with some backends');
-		}
-
-		return $this->basicOperation('fopen', $path, $hooks, $mode);
-	}
-
-	/**
-	 * @param string $path
-	 * @return bool|string
-	 * @throws \OCP\Files\InvalidPathException
-	 */
-	public function toTmpFile($path) {
-		$this->assertPathLength($path);
-		if (Filesystem::isValidPath($path)) {
-			$source = $this->fopen($path, 'r');
-			if ($source) {
-				$extension = pathinfo($path, PATHINFO_EXTENSION);
-				$tmpFile = \OC::$server->getTempManager()->getTemporaryFile($extension);
-				file_put_contents($tmpFile, $source);
-				return $tmpFile;
-			} else {
-				return false;
-			}
-		} else {
-			return false;
-		}
-	}
-
-	/**
-	 * @param string $tmpFile
-	 * @param string $path
-	 * @return bool|mixed
-	 * @throws \OCP\Files\InvalidPathException
-	 */
-	public function fromTmpFile($tmpFile, $path) {
-		$this->assertPathLength($path);
-		if (Filesystem::isValidPath($path)) {
-
-			// Get directory that the file is going into
-			$filePath = dirname($path);
-
-			// Create the directories if any
-			if (!$this->file_exists($filePath)) {
-				$result = $this->createParentDirectories($filePath);
-				if ($result === false) {
-					return false;
-				}
-			}
-
-			$source = fopen($tmpFile, 'r');
-			if ($source) {
-				$result = $this->file_put_contents($path, $source);
-				// $this->file_put_contents() might have already closed
-				// the resource, so we check it, before trying to close it
-				// to avoid messages in the error log.
-				if (is_resource($source)) {
-					fclose($source);
-				}
-				unlink($tmpFile);
-				return $result;
-			} else {
-				return false;
-			}
-		} else {
-			return false;
-		}
-	}
-
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 * @throws \OCP\Files\InvalidPathException
-	 */
-	public function getMimeType($path) {
-		$this->assertPathLength($path);
-		return $this->basicOperation('getMimeType', $path);
-	}
-
-	/**
-	 * @param string $type
-	 * @param string $path
-	 * @param bool $raw
-	 * @return bool|null|string
-	 */
-	public function hash($type, $path, $raw = false) {
-		$postFix = (substr($path, -1) === '/') ? '/' : '';
-		$absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
-		if (Filesystem::isValidPath($path)) {
-			$path = $this->getRelativePath($absolutePath);
-			if ($path == null) {
-				return false;
-			}
-			if ($this->shouldEmitHooks($path)) {
-				\OC_Hook::emit(
-					Filesystem::CLASSNAME,
-					Filesystem::signal_read,
-					array(Filesystem::signal_param_path => $this->getHookPath($path))
-				);
-			}
-			list($storage, $internalPath) = Filesystem::resolvePath($absolutePath . $postFix);
-			if ($storage) {
-				return $storage->hash($type, $internalPath, $raw);
-			}
-		}
-		return null;
-	}
-
-	/**
-	 * @param string $path
-	 * @return mixed
-	 * @throws \OCP\Files\InvalidPathException
-	 */
-	public function free_space($path = '/') {
-		$this->assertPathLength($path);
-		$result = $this->basicOperation('free_space', $path);
-		if ($result === null) {
-			throw new InvalidPathException();
-		}
-		return $result;
-	}
-
-	/**
-	 * abstraction layer for basic filesystem functions: wrapper for \OC\Files\Storage\Storage
-	 *
-	 * @param string $operation
-	 * @param string $path
-	 * @param array $hooks (optional)
-	 * @param mixed $extraParam (optional)
-	 * @return mixed
-	 * @throws \Exception
-	 *
-	 * This method takes requests for basic filesystem functions (e.g. reading & writing
-	 * files), processes hooks and proxies, sanitises paths, and finally passes them on to
-	 * \OC\Files\Storage\Storage for delegation to a storage backend for execution
-	 */
-	private function basicOperation($operation, $path, $hooks = [], $extraParam = null) {
-		$postFix = (substr($path, -1) === '/') ? '/' : '';
-		$absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
-		if (Filesystem::isValidPath($path)
-			and !Filesystem::isFileBlacklisted($path)
-		) {
-			$path = $this->getRelativePath($absolutePath);
-			if ($path == null) {
-				return false;
-			}
-
-			if (in_array('write', $hooks) || in_array('delete', $hooks) || in_array('read', $hooks)) {
-				// always a shared lock during pre-hooks so the hook can read the file
-				$this->lockFile($path, ILockingProvider::LOCK_SHARED);
-			}
-
-			$run = $this->runHooks($hooks, $path);
-			/** @var \OC\Files\Storage\Storage $storage */
-			list($storage, $internalPath) = Filesystem::resolvePath($absolutePath . $postFix);
-			if ($run and $storage) {
-				if (in_array('write', $hooks) || in_array('delete', $hooks)) {
-					try {
-						$this->changeLock($path, ILockingProvider::LOCK_EXCLUSIVE);
-					} catch (LockedException $e) {
-						// release the shared lock we acquired before quiting
-						$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-						throw $e;
-					}
-				}
-				try {
-					if (!is_null($extraParam)) {
-						$result = $storage->$operation($internalPath, $extraParam);
-					} else {
-						$result = $storage->$operation($internalPath);
-					}
-				} catch (\Exception $e) {
-					if (in_array('write', $hooks) || in_array('delete', $hooks)) {
-						$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
-					} else if (in_array('read', $hooks)) {
-						$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-					}
-					throw $e;
-				}
-
-				if ($result && in_array('delete', $hooks) and $result) {
-					$this->removeUpdate($storage, $internalPath);
-				}
-				if ($result && in_array('write', $hooks,  true) && $operation !== 'fopen' && $operation !== 'touch') {
-					$this->writeUpdate($storage, $internalPath);
-				}
-				if ($result && in_array('touch', $hooks)) {
-					$this->writeUpdate($storage, $internalPath, $extraParam);
-				}
-
-				if ((in_array('write', $hooks) || in_array('delete', $hooks)) && ($operation !== 'fopen' || $result === false)) {
-					$this->changeLock($path, ILockingProvider::LOCK_SHARED);
-				}
-
-				$unlockLater = false;
-				if ($this->lockingEnabled && $operation === 'fopen' && is_resource($result)) {
-					$unlockLater = true;
-					// make sure our unlocking callback will still be called if connection is aborted
-					ignore_user_abort(true);
-					$result = CallbackWrapper::wrap($result, null, null, function () use ($hooks, $path) {
-						if (in_array('write', $hooks)) {
-							$this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
-						} else if (in_array('read', $hooks)) {
-							$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-						}
-					});
-				}
-
-				if ($this->shouldEmitHooks($path) && $result !== false) {
-					if ($operation != 'fopen') { //no post hooks for fopen, the file stream is still open
-						$this->runHooks($hooks, $path, true);
-					}
-				}
-
-				if (!$unlockLater
-					&& (in_array('write', $hooks) || in_array('delete', $hooks) || in_array('read', $hooks))
-				) {
-					$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-				}
-				return $result;
-			} else {
-				$this->unlockFile($path, ILockingProvider::LOCK_SHARED);
-			}
-		}
-		return null;
-	}
-
-	/**
-	 * get the path relative to the default root for hook usage
-	 *
-	 * @param string $path
-	 * @return string
-	 */
-	private function getHookPath($path) {
-		if (!Filesystem::getView()) {
-			return $path;
-		}
-		return Filesystem::getView()->getRelativePath($this->getAbsolutePath($path));
-	}
-
-	private function shouldEmitHooks($path = '') {
-		if ($path && Cache\Scanner::isPartialFile($path)) {
-			return false;
-		}
-		if (!Filesystem::$loaded) {
-			return false;
-		}
-		$defaultRoot = Filesystem::getRoot();
-		if ($defaultRoot === null) {
-			return false;
-		}
-		if ($this->fakeRoot === $defaultRoot) {
-			return true;
-		}
-		$fullPath = $this->getAbsolutePath($path);
-
-		if ($fullPath === $defaultRoot) {
-			return true;
-		}
-
-		return (strlen($fullPath) > strlen($defaultRoot)) && (substr($fullPath, 0, strlen($defaultRoot) + 1) === $defaultRoot . '/');
-	}
-
-	/**
-	 * @param string[] $hooks
-	 * @param string $path
-	 * @param bool $post
-	 * @return bool
-	 */
-	private function runHooks($hooks, $path, $post = false) {
-		$relativePath = $path;
-		$path = $this->getHookPath($path);
-		$prefix = $post ? 'post_' : '';
-		$run = true;
-		if ($this->shouldEmitHooks($relativePath)) {
-			foreach ($hooks as $hook) {
-				if ($hook != 'read') {
-					\OC_Hook::emit(
-						Filesystem::CLASSNAME,
-						$prefix . $hook,
-						array(
-							Filesystem::signal_param_run => &$run,
-							Filesystem::signal_param_path => $path
-						)
-					);
-				} elseif (!$post) {
-					\OC_Hook::emit(
-						Filesystem::CLASSNAME,
-						$prefix . $hook,
-						array(
-							Filesystem::signal_param_path => $path
-						)
-					);
-				}
-			}
-		}
-		return $run;
-	}
-
-	/**
-	 * check if a file or folder has been updated since $time
-	 *
-	 * @param string $path
-	 * @param int $time
-	 * @return bool
-	 */
-	public function hasUpdated($path, $time) {
-		return $this->basicOperation('hasUpdated', $path, array(), $time);
-	}
-
-	/**
-	 * @param string $ownerId
-	 * @return \OC\User\User
-	 */
-	private function getUserObjectForOwner($ownerId) {
-		$owner = $this->userManager->get($ownerId);
-		if ($owner instanceof IUser) {
-			return $owner;
-		} else {
-			return new User($ownerId, null, \OC::$server->getEventDispatcher());
-		}
-	}
-
-	/**
-	 * Get file info from cache
-	 *
-	 * If the file is not in cached it will be scanned
-	 * If the file has changed on storage the cache will be updated
-	 *
-	 * @param \OC\Files\Storage\Storage $storage
-	 * @param string $internalPath
-	 * @param string $relativePath
-	 * @return ICacheEntry|bool
-	 */
-	private function getCacheEntry($storage, $internalPath, $relativePath) {
-		$cache = $storage->getCache($internalPath);
-		$data = $cache->get($internalPath);
-		$watcher = $storage->getWatcher($internalPath);
-
-		try {
-			// if the file is not in the cache or needs to be updated, trigger the scanner and reload the data
-			if (!$data || $data['size'] === -1) {
-				if (!$storage->file_exists($internalPath)) {
-					return false;
-				}
-				// don't need to get a lock here since the scanner does it's own locking
-				$scanner = $storage->getScanner($internalPath);
-				$scanner->scan($internalPath, Cache\Scanner::SCAN_SHALLOW);
-				$data = $cache->get($internalPath);
-			} else if (!Cache\Scanner::isPartialFile($internalPath) && $watcher->needsUpdate($internalPath, $data)) {
-				$this->lockFile($relativePath, ILockingProvider::LOCK_SHARED);
-				$watcher->update($internalPath, $data);
-				$storage->getPropagator()->propagateChange($internalPath, time());
-				$data = $cache->get($internalPath);
-				$this->unlockFile($relativePath, ILockingProvider::LOCK_SHARED);
-			}
-		} catch (LockedException $e) {
-			// if the file is locked we just use the old cache info
-		}
-
-		return $data;
-	}
-
-	/**
-	 * get the filesystem info
-	 *
-	 * @param string $path
-	 * @param boolean|string $includeMountPoints true to add mountpoint sizes,
-	 * 'ext' to add only ext storage mount point sizes. Defaults to true.
-	 * defaults to true
-	 * @return \OC\Files\FileInfo|false False if file does not exist
-	 */
-	public function getFileInfo($path, $includeMountPoints = true) {
-		$this->assertPathLength($path);
-		if (!Filesystem::isValidPath($path)) {
-			return false;
-		}
-		if (Cache\Scanner::isPartialFile($path)) {
-			return $this->getPartFileInfo($path);
-		}
-		$relativePath = $path;
-		$path = Filesystem::normalizePath($this->fakeRoot . '/' . $path);
-
-		$mount = Filesystem::getMountManager()->find($path);
-		if (!$mount) {
-			\OC::$server->getLogger()->warning('Mountpoint not found for path: ' . $path);
-			return false;
-		}
-		$storage = $mount->getStorage();
-		$internalPath = $mount->getInternalPath($path);
-		if ($storage) {
-			$data = $this->getCacheEntry($storage, $internalPath, $relativePath);
-
-			if (!$data instanceof ICacheEntry) {
-				return false;
-			}
-
-			if ($mount instanceof MoveableMount && $internalPath === '') {
-				$data['permissions'] |= \OCP\Constants::PERMISSION_DELETE;
-			}
-			$ownerId = $storage->getOwner($internalPath);
-			$owner = null;
-			if ($ownerId !== null) {
-				// ownerId might be null if files are accessed with an access token without file system access
-				$owner = $this->getUserObjectForOwner($ownerId);
-			}
-			$info = new FileInfo($path, $storage, $internalPath, $data, $mount, $owner);
-
-			if ($data and isset($data['fileid'])) {
-				if ($includeMountPoints and $data['mimetype'] === 'httpd/unix-directory') {
-					//add the sizes of other mount points to the folder
-					$extOnly = ($includeMountPoints === 'ext');
-					$mounts = Filesystem::getMountManager()->findIn($path);
-					$info->setSubMounts(array_filter($mounts, function (IMountPoint $mount) use ($extOnly) {
-						$subStorage = $mount->getStorage();
-						return !($extOnly && $subStorage instanceof \OCA\Files_Sharing\SharedStorage);
-					}));
-				}
-			}
-
-			return $info;
-		} else {
-			\OC::$server->getLogger()->warning('Storage not valid for mountpoint: ' . $mount->getMountPoint());
-		}
-
-		return false;
-	}
-
-	/**
-	 * get the content of a directory
-	 *
-	 * @param string $directory path under datadirectory
-	 * @param string $mimetype_filter limit returned content to this mimetype or mimepart
-	 * @return FileInfo[]
-	 */
-	public function getDirectoryContent($directory, $mimetype_filter = '') {
-		$this->assertPathLength($directory);
-		if (!Filesystem::isValidPath($directory)) {
-			return [];
-		}
-		$path = $this->getAbsolutePath($directory);
-		$path = Filesystem::normalizePath($path);
-		$mount = $this->getMount($directory);
-		if (!$mount) {
-			return [];
-		}
-		$storage = $mount->getStorage();
-		$internalPath = $mount->getInternalPath($path);
-		if ($storage) {
-			$cache = $storage->getCache($internalPath);
-			$user = \OC_User::getUser();
-
-			$data = $this->getCacheEntry($storage, $internalPath, $directory);
-
-			if (!$data instanceof ICacheEntry || !isset($data['fileid']) || !($data->getPermissions() && Constants::PERMISSION_READ)) {
-				return [];
-			}
-
-			$folderId = $data['fileid'];
-			$contents = $cache->getFolderContentsById($folderId); //TODO: mimetype_filter
-
-			$sharingDisabled = \OCP\Util::isSharingDisabledForUser();
-
-			$fileNames = array_map(function(ICacheEntry $content) {
-				return $content->getName();
-			}, $contents);
-			/**
-			 * @var \OC\Files\FileInfo[] $fileInfos
-			 */
-			$fileInfos = array_map(function (ICacheEntry $content) use ($path, $storage, $mount, $sharingDisabled) {
-				if ($sharingDisabled) {
-					$content['permissions'] = $content['permissions'] & ~\OCP\Constants::PERMISSION_SHARE;
-				}
-				$owner = $this->getUserObjectForOwner($storage->getOwner($content['path']));
-				return new FileInfo($path . '/' . $content['name'], $storage, $content['path'], $content, $mount, $owner);
-			}, $contents);
-			$files = array_combine($fileNames, $fileInfos);
-
-			//add a folder for any mountpoint in this directory and add the sizes of other mountpoints to the folders
-			$mounts = Filesystem::getMountManager()->findIn($path);
-			$dirLength = strlen($path);
-			foreach ($mounts as $mount) {
-				$mountPoint = $mount->getMountPoint();
-				$subStorage = $mount->getStorage();
-				if ($subStorage) {
-					$subCache = $subStorage->getCache('');
-
-					$rootEntry = $subCache->get('');
-					if (!$rootEntry) {
-						$subScanner = $subStorage->getScanner('');
-						try {
-							$subScanner->scanFile('');
-						} catch (\OCP\Files\StorageNotAvailableException $e) {
-							continue;
-						} catch (\OCP\Files\StorageInvalidException $e) {
-							continue;
-						} catch (\Exception $e) {
-							// sometimes when the storage is not available it can be any exception
-							\OC::$server->getLogger()->logException($e, [
-								'message' => 'Exception while scanning storage "' . $subStorage->getId() . '"',
-								'level' => ILogger::ERROR,
-								'app' => 'lib',
-							]);
-							continue;
-						}
-						$rootEntry = $subCache->get('');
-					}
-
-					if ($rootEntry && ($rootEntry->getPermissions() && Constants::PERMISSION_READ)) {
-						$relativePath = trim(substr($mountPoint, $dirLength), '/');
-						if ($pos = strpos($relativePath, '/')) {
-							//mountpoint inside subfolder add size to the correct folder
-							$entryName = substr($relativePath, 0, $pos);
-							foreach ($files as &$entry) {
-								if ($entry->getName() === $entryName) {
-									$entry->addSubEntry($rootEntry, $mountPoint);
-								}
-							}
-						} else { //mountpoint in this folder, add an entry for it
-							$rootEntry['name'] = $relativePath;
-							$rootEntry['type'] = $rootEntry['mimetype'] === 'httpd/unix-directory' ? 'dir' : 'file';
-							$permissions = $rootEntry['permissions'];
-							// do not allow renaming/deleting the mount point if they are not shared files/folders
-							// for shared files/folders we use the permissions given by the owner
-							if ($mount instanceof MoveableMount) {
-								$rootEntry['permissions'] = $permissions | \OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE;
-							} else {
-								$rootEntry['permissions'] = $permissions & (\OCP\Constants::PERMISSION_ALL - (\OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE));
-							}
-
-							$rootEntry['path'] = substr(Filesystem::normalizePath($path . '/' . $rootEntry['name']), strlen($user) + 2); // full path without /$user/
-
-							// if sharing was disabled for the user we remove the share permissions
-							if (\OCP\Util::isSharingDisabledForUser()) {
-								$rootEntry['permissions'] = $rootEntry['permissions'] & ~\OCP\Constants::PERMISSION_SHARE;
-							}
-
-							$owner = $this->getUserObjectForOwner($subStorage->getOwner(''));
-							$files[$rootEntry->getName()] = new FileInfo($path . '/' . $rootEntry['name'], $subStorage, '', $rootEntry, $mount, $owner);
-						}
-					}
-				}
-			}
-
-			if ($mimetype_filter) {
-				$files = array_filter($files, function (FileInfo $file) use ($mimetype_filter) {
-					if (strpos($mimetype_filter, '/')) {
-						return $file->getMimetype() === $mimetype_filter;
-					} else {
-						return $file->getMimePart() === $mimetype_filter;
-					}
-				});
-			}
-
-			return array_values($files);
-		} else {
-			return [];
-		}
-	}
-
-	/**
-	 * change file metadata
-	 *
-	 * @param string $path
-	 * @param array|\OCP\Files\FileInfo $data
-	 * @return int
-	 *
-	 * returns the fileid of the updated file
-	 */
-	public function putFileInfo($path, $data) {
-		$this->assertPathLength($path);
-		if ($data instanceof FileInfo) {
-			$data = $data->getData();
-		}
-		$path = Filesystem::normalizePath($this->fakeRoot . '/' . $path);
-		/**
-		 * @var \OC\Files\Storage\Storage $storage
-		 * @var string $internalPath
-		 */
-		list($storage, $internalPath) = Filesystem::resolvePath($path);
-		if ($storage) {
-			$cache = $storage->getCache($path);
-
-			if (!$cache->inCache($internalPath)) {
-				$scanner = $storage->getScanner($internalPath);
-				$scanner->scan($internalPath, Cache\Scanner::SCAN_SHALLOW);
-			}
-
-			return $cache->put($internalPath, $data);
-		} else {
-			return -1;
-		}
-	}
-
-	/**
-	 * search for files with the name matching $query
-	 *
-	 * @param string $query
-	 * @return FileInfo[]
-	 */
-	public function search($query) {
-		return $this->searchCommon('search', array('%' . $query . '%'));
-	}
-
-	/**
-	 * search for files with the name matching $query
-	 *
-	 * @param string $query
-	 * @return FileInfo[]
-	 */
-	public function searchRaw($query) {
-		return $this->searchCommon('search', array($query));
-	}
-
-	/**
-	 * search for files by mimetype
-	 *
-	 * @param string $mimetype
-	 * @return FileInfo[]
-	 */
-	public function searchByMime($mimetype) {
-		return $this->searchCommon('searchByMime', array($mimetype));
-	}
-
-	/**
-	 * search for files by tag
-	 *
-	 * @param string|int $tag name or tag id
-	 * @param string $userId owner of the tags
-	 * @return FileInfo[]
-	 */
-	public function searchByTag($tag, $userId) {
-		return $this->searchCommon('searchByTag', array($tag, $userId));
-	}
-
-	/**
-	 * @param string $method cache method
-	 * @param array $args
-	 * @return FileInfo[]
-	 */
-	private function searchCommon($method, $args) {
-		$files = array();
-		$rootLength = strlen($this->fakeRoot);
-
-		$mount = $this->getMount('');
-		$mountPoint = $mount->getMountPoint();
-		$storage = $mount->getStorage();
-		if ($storage) {
-			$cache = $storage->getCache('');
-
-			$results = call_user_func_array(array($cache, $method), $args);
-			foreach ($results as $result) {
-				if (substr($mountPoint . $result['path'], 0, $rootLength + 1) === $this->fakeRoot . '/') {
-					$internalPath = $result['path'];
-					$path = $mountPoint . $result['path'];
-					$result['path'] = substr($mountPoint . $result['path'], $rootLength);
-					$owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
-					$files[] = new FileInfo($path, $storage, $internalPath, $result, $mount, $owner);
-				}
-			}
-
-			$mounts = Filesystem::getMountManager()->findIn($this->fakeRoot);
-			foreach ($mounts as $mount) {
-				$mountPoint = $mount->getMountPoint();
-				$storage = $mount->getStorage();
-				if ($storage) {
-					$cache = $storage->getCache('');
-
-					$relativeMountPoint = substr($mountPoint, $rootLength);
-					$results = call_user_func_array(array($cache, $method), $args);
-					if ($results) {
-						foreach ($results as $result) {
-							$internalPath = $result['path'];
-							$result['path'] = rtrim($relativeMountPoint . $result['path'], '/');
-							$path = rtrim($mountPoint . $internalPath, '/');
-							$owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
-							$files[] = new FileInfo($path, $storage, $internalPath, $result, $mount, $owner);
-						}
-					}
-				}
-			}
-		}
-		return $files;
-	}
-
-	/**
-	 * Get the owner for a file or folder
-	 *
-	 * @param string $path
-	 * @return string the user id of the owner
-	 * @throws NotFoundException
-	 */
-	public function getOwner($path) {
-		$info = $this->getFileInfo($path);
-		if (!$info) {
-			throw new NotFoundException($path . ' not found while trying to get owner');
-		}
-		return $info->getOwner()->getUID();
-	}
-
-	/**
-	 * get the ETag for a file or folder
-	 *
-	 * @param string $path
-	 * @return string
-	 */
-	public function getETag($path) {
-		/**
-		 * @var Storage\Storage $storage
-		 * @var string $internalPath
-		 */
-		list($storage, $internalPath) = $this->resolvePath($path);
-		if ($storage) {
-			return $storage->getETag($internalPath);
-		} else {
-			return null;
-		}
-	}
-
-	/**
-	 * Get the path of a file by id, relative to the view
-	 *
-	 * Note that the resulting path is not guarantied to be unique for the id, multiple paths can point to the same file
-	 *
-	 * @param int $id
-	 * @throws NotFoundException
-	 * @return string
-	 */
-	public function getPath($id) {
-		$id = (int)$id;
-		$manager = Filesystem::getMountManager();
-		$mounts = $manager->findIn($this->fakeRoot);
-		$mounts[] = $manager->find($this->fakeRoot);
-		// reverse the array so we start with the storage this view is in
-		// which is the most likely to contain the file we're looking for
-		$mounts = array_reverse($mounts);
-
-		// put non shared mounts in front of the shared mount
-		// this prevent unneeded recursion into shares
-		usort($mounts, function(IMountPoint $a, IMountPoint $b) {
-			return $a instanceof SharedMount && (!$b instanceof SharedMount) ? 1 : -1;
-		});
-
-		foreach ($mounts as $mount) {
-			/**
-			 * @var \OC\Files\Mount\MountPoint $mount
-			 */
-			if ($mount->getStorage()) {
-				$cache = $mount->getStorage()->getCache();
-				$internalPath = $cache->getPathById($id);
-				if (is_string($internalPath)) {
-					$fullPath = $mount->getMountPoint() . $internalPath;
-					if (!is_null($path = $this->getRelativePath($fullPath))) {
-						return $path;
-					}
-				}
-			}
-		}
-		throw new NotFoundException(sprintf('File with id "%s" has not been found.', $id));
-	}
-
-	/**
-	 * @param string $path
-	 * @throws InvalidPathException
-	 */
-	private function assertPathLength($path) {
-		$maxLen = min(PHP_MAXPATHLEN, 4000);
-		// Check for the string length - performed using isset() instead of strlen()
-		// because isset() is about 5x-40x faster.
-		if (isset($path[$maxLen])) {
-			$pathLen = strlen($path);
-			throw new \OCP\Files\InvalidPathException("Path length($pathLen) exceeds max path length($maxLen): $path");
-		}
-	}
-
-	/**
-	 * check if it is allowed to move a mount point to a given target.
-	 * It is not allowed to move a mount point into a different mount point or
-	 * into an already shared folder
-	 *
-	 * @param IStorage $targetStorage
-	 * @param string $targetInternalPath
-	 * @return boolean
-	 */
-	private function targetIsNotShared(IStorage $targetStorage, string $targetInternalPath) {
-
-		// note: cannot use the view because the target is already locked
-		$fileId = (int)$targetStorage->getCache()->getId($targetInternalPath);
-		if ($fileId === -1) {
-			// target might not exist, need to check parent instead
-			$fileId = (int)$targetStorage->getCache()->getId(dirname($targetInternalPath));
-		}
-
-		// check if any of the parents were shared by the current owner (include collections)
-		$shares = \OCP\Share::getItemShared(
-			'folder',
-			$fileId,
-			\OCP\Share::FORMAT_NONE,
-			null,
-			true
-		);
-
-		if (count($shares) > 0) {
-			\OCP\Util::writeLog('files',
-				'It is not allowed to move one mount point into a shared folder',
-				ILogger::DEBUG);
-			return false;
-		}
-
-		return true;
-	}
-
-	/**
-	 * Get a fileinfo object for files that are ignored in the cache (part files)
-	 *
-	 * @param string $path
-	 * @return \OCP\Files\FileInfo
-	 */
-	private function getPartFileInfo($path) {
-		$mount = $this->getMount($path);
-		$storage = $mount->getStorage();
-		$internalPath = $mount->getInternalPath($this->getAbsolutePath($path));
-		$owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
-		return new FileInfo(
-			$this->getAbsolutePath($path),
-			$storage,
-			$internalPath,
-			[
-				'fileid' => null,
-				'mimetype' => $storage->getMimeType($internalPath),
-				'name' => basename($path),
-				'etag' => null,
-				'size' => $storage->filesize($internalPath),
-				'mtime' => $storage->filemtime($internalPath),
-				'encrypted' => false,
-				'permissions' => \OCP\Constants::PERMISSION_ALL
-			],
-			$mount,
-			$owner
-		);
-	}
-
-	/**
-	 * @param string $path
-	 * @param string $fileName
-	 * @throws InvalidPathException
-	 */
-	public function verifyPath($path, $fileName) {
-		try {
-			/** @type \OCP\Files\Storage $storage */
-			list($storage, $internalPath) = $this->resolvePath($path);
-			$storage->verifyPath($internalPath, $fileName);
-		} catch (ReservedWordException $ex) {
-			$l = \OC::$server->getL10N('lib');
-			throw new InvalidPathException($l->t('File name is a reserved word'));
-		} catch (InvalidCharacterInPathException $ex) {
-			$l = \OC::$server->getL10N('lib');
-			throw new InvalidPathException($l->t('File name contains at least one invalid character'));
-		} catch (FileNameTooLongException $ex) {
-			$l = \OC::$server->getL10N('lib');
-			throw new InvalidPathException($l->t('File name is too long'));
-		} catch (InvalidDirectoryException $ex) {
-			$l = \OC::$server->getL10N('lib');
-			throw new InvalidPathException($l->t('Dot files are not allowed'));
-		} catch (EmptyFileNameException $ex) {
-			$l = \OC::$server->getL10N('lib');
-			throw new InvalidPathException($l->t('Empty filename is not allowed'));
-		}
-	}
-
-	/**
-	 * get all parent folders of $path
-	 *
-	 * @param string $path
-	 * @return string[]
-	 */
-	private function getParents($path) {
-		$path = trim($path, '/');
-		if (!$path) {
-			return [];
-		}
-
-		$parts = explode('/', $path);
-
-		// remove the single file
-		array_pop($parts);
-		$result = array('/');
-		$resultPath = '';
-		foreach ($parts as $part) {
-			if ($part) {
-				$resultPath .= '/' . $part;
-				$result[] = $resultPath;
-			}
-		}
-		return $result;
-	}
-
-	/**
-	 * Returns the mount point for which to lock
-	 *
-	 * @param string $absolutePath absolute path
-	 * @param bool $useParentMount true to return parent mount instead of whatever
-	 * is mounted directly on the given path, false otherwise
-	 * @return \OC\Files\Mount\MountPoint mount point for which to apply locks
-	 */
-	private function getMountForLock($absolutePath, $useParentMount = false) {
-		$results = [];
-		$mount = Filesystem::getMountManager()->find($absolutePath);
-		if (!$mount) {
-			return $results;
-		}
-
-		if ($useParentMount) {
-			// find out if something is mounted directly on the path
-			$internalPath = $mount->getInternalPath($absolutePath);
-			if ($internalPath === '') {
-				// resolve the parent mount instead
-				$mount = Filesystem::getMountManager()->find(dirname($absolutePath));
-			}
-		}
-
-		return $mount;
-	}
-
-	/**
-	 * Lock the given path
-	 *
-	 * @param string $path the path of the file to lock, relative to the view
-	 * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
-	 * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
-	 *
-	 * @return bool False if the path is excluded from locking, true otherwise
-	 * @throws \OCP\Lock\LockedException if the path is already locked
-	 */
-	private function lockPath($path, $type, $lockMountPoint = false) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$absolutePath = Filesystem::normalizePath($absolutePath);
-		if (!$this->shouldLockFile($absolutePath)) {
-			return false;
-		}
-
-		$mount = $this->getMountForLock($absolutePath, $lockMountPoint);
-		if ($mount) {
-			try {
-				$storage = $mount->getStorage();
-				if ($storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
-					$storage->acquireLock(
-						$mount->getInternalPath($absolutePath),
-						$type,
-						$this->lockingProvider
-					);
-				}
-			} catch (\OCP\Lock\LockedException $e) {
-				// rethrow with the a human-readable path
-				throw new \OCP\Lock\LockedException(
-					$this->getPathRelativeToFiles($absolutePath),
-					$e
-				);
-			}
-		}
-
-		return true;
-	}
-
-	/**
-	 * Change the lock type
-	 *
-	 * @param string $path the path of the file to lock, relative to the view
-	 * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
-	 * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
-	 *
-	 * @return bool False if the path is excluded from locking, true otherwise
-	 * @throws \OCP\Lock\LockedException if the path is already locked
-	 */
-	public function changeLock($path, $type, $lockMountPoint = false) {
-		$path = Filesystem::normalizePath($path);
-		$absolutePath = $this->getAbsolutePath($path);
-		$absolutePath = Filesystem::normalizePath($absolutePath);
-		if (!$this->shouldLockFile($absolutePath)) {
-			return false;
-		}
-
-		$mount = $this->getMountForLock($absolutePath, $lockMountPoint);
-		if ($mount) {
-			try {
-				$storage = $mount->getStorage();
-				if ($storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
-					$storage->changeLock(
-						$mount->getInternalPath($absolutePath),
-						$type,
-						$this->lockingProvider
-					);
-				}
-			} catch (\OCP\Lock\LockedException $e) {
-				try {
-					// rethrow with the a human-readable path
-					throw new \OCP\Lock\LockedException(
-						$this->getPathRelativeToFiles($absolutePath),
-						$e
-					);
-				} catch (\InvalidArgumentException $e) {
-					throw new \OCP\Lock\LockedException(
-						$absolutePath,
-						$e
-					);
-				}
-			}
-		}
-
-		return true;
-	}
-
-	/**
-	 * Unlock the given path
-	 *
-	 * @param string $path the path of the file to unlock, relative to the view
-	 * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
-	 * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
-	 *
-	 * @return bool False if the path is excluded from locking, true otherwise
-	 */
-	private function unlockPath($path, $type, $lockMountPoint = false) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$absolutePath = Filesystem::normalizePath($absolutePath);
-		if (!$this->shouldLockFile($absolutePath)) {
-			return false;
-		}
-
-		$mount = $this->getMountForLock($absolutePath, $lockMountPoint);
-		if ($mount) {
-			$storage = $mount->getStorage();
-			if ($storage && $storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
-				$storage->releaseLock(
-					$mount->getInternalPath($absolutePath),
-					$type,
-					$this->lockingProvider
-				);
-			}
-		}
-
-		return true;
-	}
-
-	/**
-	 * Lock a path and all its parents up to the root of the view
-	 *
-	 * @param string $path the path of the file to lock relative to the view
-	 * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
-	 * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
-	 *
-	 * @return bool False if the path is excluded from locking, true otherwise
-	 */
-	public function lockFile($path, $type, $lockMountPoint = false) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$absolutePath = Filesystem::normalizePath($absolutePath);
-		if (!$this->shouldLockFile($absolutePath)) {
-			return false;
-		}
-
-		$this->lockPath($path, $type, $lockMountPoint);
-
-		$parents = $this->getParents($path);
-		foreach ($parents as $parent) {
-			$this->lockPath($parent, ILockingProvider::LOCK_SHARED);
-		}
-
-		return true;
-	}
-
-	/**
-	 * Unlock a path and all its parents up to the root of the view
-	 *
-	 * @param string $path the path of the file to lock relative to the view
-	 * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
-	 * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
-	 *
-	 * @return bool False if the path is excluded from locking, true otherwise
-	 */
-	public function unlockFile($path, $type, $lockMountPoint = false) {
-		$absolutePath = $this->getAbsolutePath($path);
-		$absolutePath = Filesystem::normalizePath($absolutePath);
-		if (!$this->shouldLockFile($absolutePath)) {
-			return false;
-		}
-
-		$this->unlockPath($path, $type, $lockMountPoint);
-
-		$parents = $this->getParents($path);
-		foreach ($parents as $parent) {
-			$this->unlockPath($parent, ILockingProvider::LOCK_SHARED);
-		}
-
-		return true;
-	}
-
-	/**
-	 * Only lock files in data/user/files/
-	 *
-	 * @param string $path Absolute path to the file/folder we try to (un)lock
-	 * @return bool
-	 */
-	protected function shouldLockFile($path) {
-		$path = Filesystem::normalizePath($path);
-
-		$pathSegments = explode('/', $path);
-		if (isset($pathSegments[2])) {
-			// E.g.: /username/files/path-to-file
-			return ($pathSegments[2] === 'files') && (count($pathSegments) > 3);
-		}
-
-		return strpos($path, '/appdata_') !== 0;
-	}
-
-	/**
-	 * Shortens the given absolute path to be relative to
-	 * "$user/files".
-	 *
-	 * @param string $absolutePath absolute path which is under "files"
-	 *
-	 * @return string path relative to "files" with trimmed slashes or null
-	 * if the path was NOT relative to files
-	 *
-	 * @throws \InvalidArgumentException if the given path was not under "files"
-	 * @since 8.1.0
-	 */
-	public function getPathRelativeToFiles($absolutePath) {
-		$path = Filesystem::normalizePath($absolutePath);
-		$parts = explode('/', trim($path, '/'), 3);
-		// "$user", "files", "path/to/dir"
-		if (!isset($parts[1]) || $parts[1] !== 'files') {
-			$this->logger->error(
-				'$absolutePath must be relative to "files", value is "%s"',
-				[
-					$absolutePath
-				]
-			);
-			throw new \InvalidArgumentException('$absolutePath must be relative to "files"');
-		}
-		if (isset($parts[2])) {
-			return $parts[2];
-		}
-		return '';
-	}
-
-	/**
-	 * @param string $filename
-	 * @return array
-	 * @throws \OC\User\NoUserException
-	 * @throws NotFoundException
-	 */
-	public function getUidAndFilename($filename) {
-		$info = $this->getFileInfo($filename);
-		if (!$info instanceof \OCP\Files\FileInfo) {
-			throw new NotFoundException($this->getAbsolutePath($filename) . ' not found');
-		}
-		$uid = $info->getOwner()->getUID();
-		if ($uid != \OCP\User::getUser()) {
-			Filesystem::initMountPoints($uid);
-			$ownerView = new View('/' . $uid . '/files');
-			try {
-				$filename = $ownerView->getPath($info['fileid']);
-			} catch (NotFoundException $e) {
-				throw new NotFoundException('File with id ' . $info['fileid'] . ' not found for user ' . $uid);
-			}
-		}
-		return [$uid, $filename];
-	}
-
-	/**
-	 * Creates parent non-existing folders
-	 *
-	 * @param string $filePath
-	 * @return bool
-	 */
-	private function createParentDirectories($filePath) {
-		$directoryParts = explode('/', $filePath);
-		$directoryParts = array_filter($directoryParts);
-		foreach ($directoryParts as $key => $part) {
-			$currentPathElements = array_slice($directoryParts, 0, $key);
-			$currentPath = '/' . implode('/', $currentPathElements);
-			if ($this->is_file($currentPath)) {
-				return false;
-			}
-			if (!$this->file_exists($currentPath)) {
-				$this->mkdir($currentPath);
-			}
-		}
-
-		return true;
-	}
+    /** @var string */
+    private $fakeRoot = '';
+
+    /**
+     * @var \OCP\Lock\ILockingProvider
+     */
+    protected $lockingProvider;
+
+    private $lockingEnabled;
+
+    private $updaterEnabled = true;
+
+    /** @var \OC\User\Manager */
+    private $userManager;
+
+    /** @var \OCP\ILogger */
+    private $logger;
+
+    /**
+     * @param string $root
+     * @throws \Exception If $root contains an invalid path
+     */
+    public function __construct($root = '') {
+        if (is_null($root)) {
+            throw new \InvalidArgumentException('Root can\'t be null');
+        }
+        if (!Filesystem::isValidPath($root)) {
+            throw new \Exception();
+        }
+
+        $this->fakeRoot = $root;
+        $this->lockingProvider = \OC::$server->getLockingProvider();
+        $this->lockingEnabled = !($this->lockingProvider instanceof \OC\Lock\NoopLockingProvider);
+        $this->userManager = \OC::$server->getUserManager();
+        $this->logger = \OC::$server->getLogger();
+    }
+
+    public function getAbsolutePath($path = '/') {
+        if ($path === null) {
+            return null;
+        }
+        $this->assertPathLength($path);
+        if ($path === '') {
+            $path = '/';
+        }
+        if ($path[0] !== '/') {
+            $path = '/' . $path;
+        }
+        return $this->fakeRoot . $path;
+    }
+
+    /**
+     * change the root to a fake root
+     *
+     * @param string $fakeRoot
+     * @return boolean|null
+     */
+    public function chroot($fakeRoot) {
+        if (!$fakeRoot == '') {
+            if ($fakeRoot[0] !== '/') {
+                $fakeRoot = '/' . $fakeRoot;
+            }
+        }
+        $this->fakeRoot = $fakeRoot;
+    }
+
+    /**
+     * get the fake root
+     *
+     * @return string
+     */
+    public function getRoot() {
+        return $this->fakeRoot;
+    }
+
+    /**
+     * get path relative to the root of the view
+     *
+     * @param string $path
+     * @return string
+     */
+    public function getRelativePath($path) {
+        $this->assertPathLength($path);
+        if ($this->fakeRoot == '') {
+            return $path;
+        }
+
+        if (rtrim($path, '/') === rtrim($this->fakeRoot, '/')) {
+            return '/';
+        }
+
+        // missing slashes can cause wrong matches!
+        $root = rtrim($this->fakeRoot, '/') . '/';
+
+        if (strpos($path, $root) !== 0) {
+            return null;
+        } else {
+            $path = substr($path, strlen($this->fakeRoot));
+            if (strlen($path) === 0) {
+                return '/';
+            } else {
+                return $path;
+            }
+        }
+    }
+
+    /**
+     * get the mountpoint of the storage object for a path
+     * ( note: because a storage is not always mounted inside the fakeroot, the
+     * returned mountpoint is relative to the absolute root of the filesystem
+     * and does not take the chroot into account )
+     *
+     * @param string $path
+     * @return string
+     */
+    public function getMountPoint($path) {
+        return Filesystem::getMountPoint($this->getAbsolutePath($path));
+    }
+
+    /**
+     * get the mountpoint of the storage object for a path
+     * ( note: because a storage is not always mounted inside the fakeroot, the
+     * returned mountpoint is relative to the absolute root of the filesystem
+     * and does not take the chroot into account )
+     *
+     * @param string $path
+     * @return \OCP\Files\Mount\IMountPoint
+     */
+    public function getMount($path) {
+        return Filesystem::getMountManager()->find($this->getAbsolutePath($path));
+    }
+
+    /**
+     * resolve a path to a storage and internal path
+     *
+     * @param string $path
+     * @return array an array consisting of the storage and the internal path
+     */
+    public function resolvePath($path) {
+        $a = $this->getAbsolutePath($path);
+        $p = Filesystem::normalizePath($a);
+        return Filesystem::resolvePath($p);
+    }
+
+    /**
+     * return the path to a local version of the file
+     * we need this because we can't know if a file is stored local or not from
+     * outside the filestorage and for some purposes a local file is needed
+     *
+     * @param string $path
+     * @return string
+     */
+    public function getLocalFile($path) {
+        $parent = substr($path, 0, strrpos($path, '/'));
+        $path = $this->getAbsolutePath($path);
+        list($storage, $internalPath) = Filesystem::resolvePath($path);
+        if (Filesystem::isValidPath($parent) and $storage) {
+            return $storage->getLocalFile($internalPath);
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * @param string $path
+     * @return string
+     */
+    public function getLocalFolder($path) {
+        $parent = substr($path, 0, strrpos($path, '/'));
+        $path = $this->getAbsolutePath($path);
+        list($storage, $internalPath) = Filesystem::resolvePath($path);
+        if (Filesystem::isValidPath($parent) and $storage) {
+            return $storage->getLocalFolder($internalPath);
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * the following functions operate with arguments and return values identical
+     * to those of their PHP built-in equivalents. Mostly they are merely wrappers
+     * for \OC\Files\Storage\Storage via basicOperation().
+     */
+    public function mkdir($path) {
+        return $this->basicOperation('mkdir', $path, array('create', 'write'));
+    }
+
+    /**
+     * remove mount point
+     *
+     * @param \OC\Files\Mount\MoveableMount $mount
+     * @param string $path relative to data/
+     * @return boolean
+     */
+    protected function removeMount($mount, $path) {
+        if ($mount instanceof MoveableMount) {
+            // cut of /user/files to get the relative path to data/user/files
+            $pathParts = explode('/', $path, 4);
+            $relPath = '/' . $pathParts[3];
+            $this->lockFile($relPath, ILockingProvider::LOCK_SHARED, true);
+            \OC_Hook::emit(
+                Filesystem::CLASSNAME, "umount",
+                array(Filesystem::signal_param_path => $relPath)
+            );
+            $this->changeLock($relPath, ILockingProvider::LOCK_EXCLUSIVE, true);
+            $result = $mount->removeMount();
+            $this->changeLock($relPath, ILockingProvider::LOCK_SHARED, true);
+            if ($result) {
+                \OC_Hook::emit(
+                    Filesystem::CLASSNAME, "post_umount",
+                    array(Filesystem::signal_param_path => $relPath)
+                );
+            }
+            $this->unlockFile($relPath, ILockingProvider::LOCK_SHARED, true);
+            return $result;
+        } else {
+            // do not allow deleting the storage's root / the mount point
+            // because for some storages it might delete the whole contents
+            // but isn't supposed to work that way
+            return false;
+        }
+    }
+
+    public function disableCacheUpdate() {
+        $this->updaterEnabled = false;
+    }
+
+    public function enableCacheUpdate() {
+        $this->updaterEnabled = true;
+    }
+
+    protected function writeUpdate(Storage $storage, $internalPath, $time = null) {
+        if ($this->updaterEnabled) {
+            if (is_null($time)) {
+                $time = time();
+            }
+            $storage->getUpdater()->update($internalPath, $time);
+        }
+    }
+
+    protected function removeUpdate(Storage $storage, $internalPath) {
+        if ($this->updaterEnabled) {
+            $storage->getUpdater()->remove($internalPath);
+        }
+    }
+
+    protected function renameUpdate(Storage $sourceStorage, Storage $targetStorage, $sourceInternalPath, $targetInternalPath) {
+        if ($this->updaterEnabled) {
+            $targetStorage->getUpdater()->renameFromStorage($sourceStorage, $sourceInternalPath, $targetInternalPath);
+        }
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function rmdir($path) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $mount = Filesystem::getMountManager()->find($absolutePath);
+        if ($mount->getInternalPath($absolutePath) === '') {
+            return $this->removeMount($mount, $absolutePath);
+        }
+        if ($this->is_dir($path)) {
+            $result = $this->basicOperation('rmdir', $path, array('delete'));
+        } else {
+            $result = false;
+        }
+
+        if (!$result && !$this->file_exists($path)) { //clear ghost files from the cache on delete
+            $storage = $mount->getStorage();
+            $internalPath = $mount->getInternalPath($absolutePath);
+            $storage->getUpdater()->remove($internalPath);
+        }
+        return $result;
+    }
+
+    /**
+     * @param string $path
+     * @return resource
+     */
+    public function opendir($path) {
+        return $this->basicOperation('opendir', $path, array('read'));
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function is_dir($path) {
+        if ($path == '/') {
+            return true;
+        }
+        return $this->basicOperation('is_dir', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function is_file($path) {
+        if ($path == '/') {
+            return false;
+        }
+        return $this->basicOperation('is_file', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function stat($path) {
+        return $this->basicOperation('stat', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function filetype($path) {
+        return $this->basicOperation('filetype', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function filesize($path) {
+        return $this->basicOperation('filesize', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     * @throws \OCP\Files\InvalidPathException
+     */
+    public function readfile($path) {
+        $this->assertPathLength($path);
+        @ob_end_clean();
+        $handle = $this->fopen($path, 'rb');
+        if ($handle) {
+            $chunkSize = 8192; // 8 kB chunks
+            while (!feof($handle)) {
+                echo fread($handle, $chunkSize);
+                flush();
+            }
+            fclose($handle);
+            return $this->filesize($path);
+        }
+        return false;
+    }
+
+    /**
+     * @param string $path
+     * @param int $from
+     * @param int $to
+     * @return bool|mixed
+     * @throws \OCP\Files\InvalidPathException
+     * @throws \OCP\Files\UnseekableException
+     */
+    public function readfilePart($path, $from, $to) {
+        $this->assertPathLength($path);
+        @ob_end_clean();
+        $handle = $this->fopen($path, 'rb');
+        if ($handle) {
+            $chunkSize = 8192; // 8 kB chunks
+            $startReading = true;
+
+            if ($from !== 0 && $from !== '0' && fseek($handle, $from) !== 0) {
+                // forward file handle via chunked fread because fseek seem to have failed
+
+                $end = $from + 1;
+                while (!feof($handle) && ftell($handle) < $end) {
+                    $len = $from - ftell($handle);
+                    if ($len > $chunkSize) {
+                        $len = $chunkSize;
+                    }
+                    $result = fread($handle, $len);
+
+                    if ($result === false) {
+                        $startReading = false;
+                        break;
+                    }
+                }
+            }
+
+            if ($startReading) {
+                $end = $to + 1;
+                while (!feof($handle) && ftell($handle) < $end) {
+                    $len = $end - ftell($handle);
+                    if ($len > $chunkSize) {
+                        $len = $chunkSize;
+                    }
+                    echo fread($handle, $len);
+                    flush();
+                }
+                return ftell($handle) - $from;
+            }
+
+            throw new \OCP\Files\UnseekableException('fseek error');
+        }
+        return false;
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function isCreatable($path) {
+        return $this->basicOperation('isCreatable', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function isReadable($path) {
+        return $this->basicOperation('isReadable', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function isUpdatable($path) {
+        return $this->basicOperation('isUpdatable', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function isDeletable($path) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $mount = Filesystem::getMountManager()->find($absolutePath);
+        if ($mount->getInternalPath($absolutePath) === '') {
+            return $mount instanceof MoveableMount;
+        }
+        return $this->basicOperation('isDeletable', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function isSharable($path) {
+        return $this->basicOperation('isSharable', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function file_exists($path) {
+        if ($path == '/') {
+            return true;
+        }
+        return $this->basicOperation('file_exists', $path);
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function filemtime($path) {
+        return $this->basicOperation('filemtime', $path);
+    }
+
+    /**
+     * @param string $path
+     * @param int|string $mtime
+     * @return bool
+     */
+    public function touch($path, $mtime = null) {
+        if (!is_null($mtime) and !is_numeric($mtime)) {
+            $mtime = strtotime($mtime);
+        }
+
+        $hooks = array('touch');
+
+        if (!$this->file_exists($path)) {
+            $hooks[] = 'create';
+            $hooks[] = 'write';
+        }
+        $result = $this->basicOperation('touch', $path, $hooks, $mtime);
+        if (!$result) {
+            // If create file fails because of permissions on external storage like SMB folders,
+            // check file exists and return false if not.
+            if (!$this->file_exists($path)) {
+                return false;
+            }
+            if (is_null($mtime)) {
+                $mtime = time();
+            }
+            //if native touch fails, we emulate it by changing the mtime in the cache
+            $this->putFileInfo($path, array('mtime' => floor($mtime)));
+        }
+        return true;
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     */
+    public function file_get_contents($path) {
+        return $this->basicOperation('file_get_contents', $path, array('read'));
+    }
+
+    /**
+     * @param bool $exists
+     * @param string $path
+     * @param bool $run
+     */
+    protected function emit_file_hooks_pre($exists, $path, &$run) {
+        if (!$exists) {
+            \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_create, array(
+                Filesystem::signal_param_path => $this->getHookPath($path),
+                Filesystem::signal_param_run => &$run,
+            ));
+        } else {
+            \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_update, array(
+                Filesystem::signal_param_path => $this->getHookPath($path),
+                Filesystem::signal_param_run => &$run,
+            ));
+        }
+        \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_write, array(
+            Filesystem::signal_param_path => $this->getHookPath($path),
+            Filesystem::signal_param_run => &$run,
+        ));
+    }
+
+    /**
+     * @param bool $exists
+     * @param string $path
+     */
+    protected function emit_file_hooks_post($exists, $path) {
+        if (!$exists) {
+            \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_create, array(
+                Filesystem::signal_param_path => $this->getHookPath($path),
+            ));
+        } else {
+            \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_update, array(
+                Filesystem::signal_param_path => $this->getHookPath($path),
+            ));
+        }
+        \OC_Hook::emit(Filesystem::CLASSNAME, Filesystem::signal_post_write, array(
+            Filesystem::signal_param_path => $this->getHookPath($path),
+        ));
+    }
+
+    /**
+     * @param string $path
+     * @param string|resource $data
+     * @return bool|mixed
+     * @throws \Exception
+     */
+    public function file_put_contents($path, $data) {
+        if (is_resource($data)) { //not having to deal with streams in file_put_contents makes life easier
+            $absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
+            if (Filesystem::isValidPath($path)
+                and !Filesystem::isFileBlacklisted($path)
+            ) {
+                $path = $this->getRelativePath($absolutePath);
+
+                $this->lockFile($path, ILockingProvider::LOCK_SHARED);
+
+                $exists = $this->file_exists($path);
+                $run = true;
+                if ($this->shouldEmitHooks($path)) {
+                    $this->emit_file_hooks_pre($exists, $path, $run);
+                }
+                if (!$run) {
+                    $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                    return false;
+                }
+
+                $this->changeLock($path, ILockingProvider::LOCK_EXCLUSIVE);
+
+                /** @var \OC\Files\Storage\Storage $storage */
+                list($storage, $internalPath) = $this->resolvePath($path);
+                $target = $storage->fopen($internalPath, 'w');
+                if ($target) {
+                    list (, $result) = \OC_Helper::streamCopy($data, $target);
+                    fclose($target);
+                    fclose($data);
+
+                    $this->writeUpdate($storage, $internalPath);
+
+                    $this->changeLock($path, ILockingProvider::LOCK_SHARED);
+
+                    if ($this->shouldEmitHooks($path) && $result !== false) {
+                        $this->emit_file_hooks_post($exists, $path);
+                    }
+                    $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                    return $result;
+                } else {
+                    $this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
+                    return false;
+                }
+            } else {
+                return false;
+            }
+        } else {
+            $hooks = $this->file_exists($path) ? array('update', 'write') : array('create', 'write');
+            return $this->basicOperation('file_put_contents', $path, $hooks, $data);
+        }
+    }
+
+    /**
+     * @param string $path
+     * @return bool|mixed
+     */
+    public function unlink($path) {
+        if ($path === '' || $path === '/') {
+            // do not allow deleting the root
+            return false;
+        }
+        $postFix = (substr($path, -1) === '/') ? '/' : '';
+        $absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
+        $mount = Filesystem::getMountManager()->find($absolutePath . $postFix);
+        if ($mount and $mount->getInternalPath($absolutePath) === '') {
+            return $this->removeMount($mount, $absolutePath);
+        }
+        if ($this->is_dir($path)) {
+            $result = $this->basicOperation('rmdir', $path, ['delete']);
+        } else {
+            $result = $this->basicOperation('unlink', $path, ['delete']);
+        }
+        if (!$result && !$this->file_exists($path)) { //clear ghost files from the cache on delete
+            $storage = $mount->getStorage();
+            $internalPath = $mount->getInternalPath($absolutePath);
+            $storage->getUpdater()->remove($internalPath);
+            return true;
+        } else {
+            return $result;
+        }
+    }
+
+    /**
+     * @param string $directory
+     * @return bool|mixed
+     */
+    public function deleteAll($directory) {
+        return $this->rmdir($directory);
+    }
+
+    /**
+     * Rename/move a file or folder from the source path to target path.
+     *
+     * @param string $path1 source path
+     * @param string $path2 target path
+     *
+     * @return bool|mixed
+     */
+    public function rename($path1, $path2) {
+        $absolutePath1 = Filesystem::normalizePath($this->getAbsolutePath($path1));
+        $absolutePath2 = Filesystem::normalizePath($this->getAbsolutePath($path2));
+        $result = false;
+        if (
+            Filesystem::isValidPath($path2)
+            and Filesystem::isValidPath($path1)
+            and !Filesystem::isFileBlacklisted($path2)
+        ) {
+            $path1 = $this->getRelativePath($absolutePath1);
+            $path2 = $this->getRelativePath($absolutePath2);
+            $exists = $this->file_exists($path2);
+
+            if ($path1 == null or $path2 == null) {
+                return false;
+            }
+
+            $this->lockFile($path1, ILockingProvider::LOCK_SHARED, true);
+            try {
+                $this->lockFile($path2, ILockingProvider::LOCK_SHARED, true);
+
+                $run = true;
+                if ($this->shouldEmitHooks($path1) && (Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2))) {
+                    // if it was a rename from a part file to a regular file it was a write and not a rename operation
+                    $this->emit_file_hooks_pre($exists, $path2, $run);
+                } elseif ($this->shouldEmitHooks($path1)) {
+                    \OC_Hook::emit(
+                        Filesystem::CLASSNAME, Filesystem::signal_rename,
+                        array(
+                            Filesystem::signal_param_oldpath => $this->getHookPath($path1),
+                            Filesystem::signal_param_newpath => $this->getHookPath($path2),
+                            Filesystem::signal_param_run => &$run
+                        )
+                    );
+                }
+                if ($run) {
+                    $this->verifyPath(dirname($path2), basename($path2));
+
+                    $manager = Filesystem::getMountManager();
+                    $mount1 = $this->getMount($path1);
+                    $mount2 = $this->getMount($path2);
+                    $storage1 = $mount1->getStorage();
+                    $storage2 = $mount2->getStorage();
+                    $internalPath1 = $mount1->getInternalPath($absolutePath1);
+                    $internalPath2 = $mount2->getInternalPath($absolutePath2);
+
+                    $this->changeLock($path1, ILockingProvider::LOCK_EXCLUSIVE, true);
+                    try {
+                        $this->changeLock($path2, ILockingProvider::LOCK_EXCLUSIVE, true);
+
+                        if ($internalPath1 === '') {
+                            if ($mount1 instanceof MoveableMount) {
+                                $sourceParentMount = $this->getMount(dirname($path1));
+                                if ($sourceParentMount === $mount2 && $this->targetIsNotShared($storage2, $internalPath2)) {
+                                    /**
+                                     * @var \OC\Files\Mount\MountPoint | \OC\Files\Mount\MoveableMount $mount1
+                                     */
+                                    $sourceMountPoint = $mount1->getMountPoint();
+                                    $result = $mount1->moveMount($absolutePath2);
+                                    $manager->moveMount($sourceMountPoint, $mount1->getMountPoint());
+                                } else {
+                                    $result = false;
+                                }
+                            } else {
+                                $result = false;
+                            }
+                            // moving a file/folder within the same mount point
+                        } elseif ($storage1 === $storage2) {
+                            if ($storage1) {
+                                $result = $storage1->rename($internalPath1, $internalPath2);
+                            } else {
+                                $result = false;
+                            }
+                            // moving a file/folder between storages (from $storage1 to $storage2)
+                        } else {
+                            $result = $storage2->moveFromStorage($storage1, $internalPath1, $internalPath2);
+                        }
+
+                        if ((Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2)) && $result !== false) {
+                            // if it was a rename from a part file to a regular file it was a write and not a rename operation
+                            $this->writeUpdate($storage2, $internalPath2);
+                        } else if ($result) {
+                            if ($internalPath1 !== '') { // don't do a cache update for moved mounts
+                                $this->renameUpdate($storage1, $storage2, $internalPath1, $internalPath2);
+                            }
+                        }
+                    } catch(\Exception $e) {
+                        throw $e;
+                    } finally {
+                        $this->changeLock($path1, ILockingProvider::LOCK_SHARED, true);
+                        $this->changeLock($path2, ILockingProvider::LOCK_SHARED, true);
+                    }
+
+                    if ((Cache\Scanner::isPartialFile($path1) && !Cache\Scanner::isPartialFile($path2)) && $result !== false) {
+                        if ($this->shouldEmitHooks()) {
+                            $this->emit_file_hooks_post($exists, $path2);
+                        }
+                    } elseif ($result) {
+                        if ($this->shouldEmitHooks($path1) and $this->shouldEmitHooks($path2)) {
+                            \OC_Hook::emit(
+                                Filesystem::CLASSNAME,
+                                Filesystem::signal_post_rename,
+                                array(
+                                    Filesystem::signal_param_oldpath => $this->getHookPath($path1),
+                                    Filesystem::signal_param_newpath => $this->getHookPath($path2)
+                                )
+                            );
+                        }
+                    }
+                }
+            } catch(\Exception $e) {
+                throw $e;
+            } finally {
+                $this->unlockFile($path1, ILockingProvider::LOCK_SHARED, true);
+                $this->unlockFile($path2, ILockingProvider::LOCK_SHARED, true);
+            }
+        }
+        return $result;
+    }
+
+    /**
+     * Copy a file/folder from the source path to target path
+     *
+     * @param string $path1 source path
+     * @param string $path2 target path
+     * @param bool $preserveMtime whether to preserve mtime on the copy
+     *
+     * @return bool|mixed
+     */
+    public function copy($path1, $path2, $preserveMtime = false) {
+        $absolutePath1 = Filesystem::normalizePath($this->getAbsolutePath($path1));
+        $absolutePath2 = Filesystem::normalizePath($this->getAbsolutePath($path2));
+        $result = false;
+        if (
+            Filesystem::isValidPath($path2)
+            and Filesystem::isValidPath($path1)
+            and !Filesystem::isFileBlacklisted($path2)
+        ) {
+            $path1 = $this->getRelativePath($absolutePath1);
+            $path2 = $this->getRelativePath($absolutePath2);
+
+            if ($path1 == null or $path2 == null) {
+                return false;
+            }
+            $run = true;
+
+            $this->lockFile($path2, ILockingProvider::LOCK_SHARED);
+            $this->lockFile($path1, ILockingProvider::LOCK_SHARED);
+            $lockTypePath1 = ILockingProvider::LOCK_SHARED;
+            $lockTypePath2 = ILockingProvider::LOCK_SHARED;
+
+            try {
+
+                $exists = $this->file_exists($path2);
+                if ($this->shouldEmitHooks()) {
+                    \OC_Hook::emit(
+                        Filesystem::CLASSNAME,
+                        Filesystem::signal_copy,
+                        array(
+                            Filesystem::signal_param_oldpath => $this->getHookPath($path1),
+                            Filesystem::signal_param_newpath => $this->getHookPath($path2),
+                            Filesystem::signal_param_run => &$run
+                        )
+                    );
+                    $this->emit_file_hooks_pre($exists, $path2, $run);
+                }
+                if ($run) {
+                    $mount1 = $this->getMount($path1);
+                    $mount2 = $this->getMount($path2);
+                    $storage1 = $mount1->getStorage();
+                    $internalPath1 = $mount1->getInternalPath($absolutePath1);
+                    $storage2 = $mount2->getStorage();
+                    $internalPath2 = $mount2->getInternalPath($absolutePath2);
+
+                    $this->changeLock($path2, ILockingProvider::LOCK_EXCLUSIVE);
+                    $lockTypePath2 = ILockingProvider::LOCK_EXCLUSIVE;
+
+                    if ($mount1->getMountPoint() == $mount2->getMountPoint()) {
+                        if ($storage1) {
+                            $result = $storage1->copy($internalPath1, $internalPath2);
+                        } else {
+                            $result = false;
+                        }
+                    } else {
+                        $result = $storage2->copyFromStorage($storage1, $internalPath1, $internalPath2);
+                    }
+
+                    $this->writeUpdate($storage2, $internalPath2);
+
+                    $this->changeLock($path2, ILockingProvider::LOCK_SHARED);
+                    $lockTypePath2 = ILockingProvider::LOCK_SHARED;
+
+                    if ($this->shouldEmitHooks() && $result !== false) {
+                        \OC_Hook::emit(
+                            Filesystem::CLASSNAME,
+                            Filesystem::signal_post_copy,
+                            array(
+                                Filesystem::signal_param_oldpath => $this->getHookPath($path1),
+                                Filesystem::signal_param_newpath => $this->getHookPath($path2)
+                            )
+                        );
+                        $this->emit_file_hooks_post($exists, $path2);
+                    }
+
+                }
+            } catch (\Exception $e) {
+                $this->unlockFile($path2, $lockTypePath2);
+                $this->unlockFile($path1, $lockTypePath1);
+                throw $e;
+            }
+
+            $this->unlockFile($path2, $lockTypePath2);
+            $this->unlockFile($path1, $lockTypePath1);
+
+        }
+        return $result;
+    }
+
+    /**
+     * @param string $path
+     * @param string $mode 'r' or 'w'
+     * @return resource
+     */
+    public function fopen($path, $mode) {
+        $mode = str_replace('b', '', $mode); // the binary flag is a windows only feature which we do not support
+        $hooks = array();
+        switch ($mode) {
+            case 'r':
+                $hooks[] = 'read';
+                break;
+            case 'r+':
+            case 'w+':
+            case 'x+':
+            case 'a+':
+                $hooks[] = 'read';
+                $hooks[] = 'write';
+                break;
+            case 'w':
+            case 'x':
+            case 'a':
+                $hooks[] = 'write';
+                break;
+            default:
+                \OCP\Util::writeLog('core', 'invalid mode (' . $mode . ') for ' . $path, ILogger::ERROR);
+        }
+
+        if ($mode !== 'r' && $mode !== 'w') {
+            \OC::$server->getLogger()->info('Trying to open a file with a mode other than "r" or "w" can cause severe performance issues with some backends');
+        }
+
+        return $this->basicOperation('fopen', $path, $hooks, $mode);
+    }
+
+    /**
+     * @param string $path
+     * @return bool|string
+     * @throws \OCP\Files\InvalidPathException
+     */
+    public function toTmpFile($path) {
+        $this->assertPathLength($path);
+        if (Filesystem::isValidPath($path)) {
+            $source = $this->fopen($path, 'r');
+            if ($source) {
+                $extension = pathinfo($path, PATHINFO_EXTENSION);
+                $tmpFile = \OC::$server->getTempManager()->getTemporaryFile($extension);
+                file_put_contents($tmpFile, $source);
+                return $tmpFile;
+            } else {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * @param string $tmpFile
+     * @param string $path
+     * @return bool|mixed
+     * @throws \OCP\Files\InvalidPathException
+     */
+    public function fromTmpFile($tmpFile, $path) {
+        $this->assertPathLength($path);
+        if (Filesystem::isValidPath($path)) {
+
+            // Get directory that the file is going into
+            $filePath = dirname($path);
+
+            // Create the directories if any
+            if (!$this->file_exists($filePath)) {
+                $result = $this->createParentDirectories($filePath);
+                if ($result === false) {
+                    return false;
+                }
+            }
+
+            $source = fopen($tmpFile, 'r');
+            if ($source) {
+                $result = $this->file_put_contents($path, $source);
+                // $this->file_put_contents() might have already closed
+                // the resource, so we check it, before trying to close it
+                // to avoid messages in the error log.
+                if (is_resource($source)) {
+                    fclose($source);
+                }
+                unlink($tmpFile);
+                return $result;
+            } else {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+
+    /**
+     * @param string $path
+     * @return mixed
+     * @throws \OCP\Files\InvalidPathException
+     */
+    public function getMimeType($path) {
+        $this->assertPathLength($path);
+        return $this->basicOperation('getMimeType', $path);
+    }
+
+    /**
+     * @param string $type
+     * @param string $path
+     * @param bool $raw
+     * @return bool|null|string
+     */
+    public function hash($type, $path, $raw = false) {
+        $postFix = (substr($path, -1) === '/') ? '/' : '';
+        $absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
+        if (Filesystem::isValidPath($path)) {
+            $path = $this->getRelativePath($absolutePath);
+            if ($path == null) {
+                return false;
+            }
+            if ($this->shouldEmitHooks($path)) {
+                \OC_Hook::emit(
+                    Filesystem::CLASSNAME,
+                    Filesystem::signal_read,
+                    array(Filesystem::signal_param_path => $this->getHookPath($path))
+                );
+            }
+            list($storage, $internalPath) = Filesystem::resolvePath($absolutePath . $postFix);
+            if ($storage) {
+                return $storage->hash($type, $internalPath, $raw);
+            }
+        }
+        return null;
+    }
+
+    /**
+     * @param string $path
+     * @return mixed
+     * @throws \OCP\Files\InvalidPathException
+     */
+    public function free_space($path = '/') {
+        $this->assertPathLength($path);
+        $result = $this->basicOperation('free_space', $path);
+        if ($result === null) {
+            throw new InvalidPathException();
+        }
+        return $result;
+    }
+
+    /**
+     * abstraction layer for basic filesystem functions: wrapper for \OC\Files\Storage\Storage
+     *
+     * @param string $operation
+     * @param string $path
+     * @param array $hooks (optional)
+     * @param mixed $extraParam (optional)
+     * @return mixed
+     * @throws \Exception
+     *
+     * This method takes requests for basic filesystem functions (e.g. reading & writing
+     * files), processes hooks and proxies, sanitises paths, and finally passes them on to
+     * \OC\Files\Storage\Storage for delegation to a storage backend for execution
+     */
+    private function basicOperation($operation, $path, $hooks = [], $extraParam = null) {
+        $postFix = (substr($path, -1) === '/') ? '/' : '';
+        $absolutePath = Filesystem::normalizePath($this->getAbsolutePath($path));
+        if (Filesystem::isValidPath($path)
+            and !Filesystem::isFileBlacklisted($path)
+        ) {
+            $path = $this->getRelativePath($absolutePath);
+            if ($path == null) {
+                return false;
+            }
+
+            if (in_array('write', $hooks) || in_array('delete', $hooks) || in_array('read', $hooks)) {
+                // always a shared lock during pre-hooks so the hook can read the file
+                $this->lockFile($path, ILockingProvider::LOCK_SHARED);
+            }
+
+            $run = $this->runHooks($hooks, $path);
+            /** @var \OC\Files\Storage\Storage $storage */
+            list($storage, $internalPath) = Filesystem::resolvePath($absolutePath . $postFix);
+            if ($run and $storage) {
+                if (in_array('write', $hooks) || in_array('delete', $hooks)) {
+                    try {
+                        $this->changeLock($path, ILockingProvider::LOCK_EXCLUSIVE);
+                    } catch (LockedException $e) {
+                        // release the shared lock we acquired before quiting
+                        $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                        throw $e;
+                    }
+                }
+                try {
+                    if (!is_null($extraParam)) {
+                        $result = $storage->$operation($internalPath, $extraParam);
+                    } else {
+                        $result = $storage->$operation($internalPath);
+                    }
+                } catch (\Exception $e) {
+                    if (in_array('write', $hooks) || in_array('delete', $hooks)) {
+                        $this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
+                    } else if (in_array('read', $hooks)) {
+                        $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                    }
+                    throw $e;
+                }
+
+                if ($result && in_array('delete', $hooks) and $result) {
+                    $this->removeUpdate($storage, $internalPath);
+                }
+                if ($result && in_array('write', $hooks,  true) && $operation !== 'fopen' && $operation !== 'touch') {
+                    $this->writeUpdate($storage, $internalPath);
+                }
+                if ($result && in_array('touch', $hooks)) {
+                    $this->writeUpdate($storage, $internalPath, $extraParam);
+                }
+
+                if ((in_array('write', $hooks) || in_array('delete', $hooks)) && ($operation !== 'fopen' || $result === false)) {
+                    $this->changeLock($path, ILockingProvider::LOCK_SHARED);
+                }
+
+                $unlockLater = false;
+                if ($this->lockingEnabled && $operation === 'fopen' && is_resource($result)) {
+                    $unlockLater = true;
+                    // make sure our unlocking callback will still be called if connection is aborted
+                    ignore_user_abort(true);
+                    $result = CallbackWrapper::wrap($result, null, null, function () use ($hooks, $path) {
+                        if (in_array('write', $hooks)) {
+                            $this->unlockFile($path, ILockingProvider::LOCK_EXCLUSIVE);
+                        } else if (in_array('read', $hooks)) {
+                            $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                        }
+                    });
+                }
+
+                if ($this->shouldEmitHooks($path) && $result !== false) {
+                    if ($operation != 'fopen') { //no post hooks for fopen, the file stream is still open
+                        $this->runHooks($hooks, $path, true);
+                    }
+                }
+
+                if (!$unlockLater
+                    && (in_array('write', $hooks) || in_array('delete', $hooks) || in_array('read', $hooks))
+                ) {
+                    $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+                }
+                return $result;
+            } else {
+                $this->unlockFile($path, ILockingProvider::LOCK_SHARED);
+            }
+        }
+        return null;
+    }
+
+    /**
+     * get the path relative to the default root for hook usage
+     *
+     * @param string $path
+     * @return string
+     */
+    private function getHookPath($path) {
+        if (!Filesystem::getView()) {
+            return $path;
+        }
+        return Filesystem::getView()->getRelativePath($this->getAbsolutePath($path));
+    }
+
+    private function shouldEmitHooks($path = '') {
+        if ($path && Cache\Scanner::isPartialFile($path)) {
+            return false;
+        }
+        if (!Filesystem::$loaded) {
+            return false;
+        }
+        $defaultRoot = Filesystem::getRoot();
+        if ($defaultRoot === null) {
+            return false;
+        }
+        if ($this->fakeRoot === $defaultRoot) {
+            return true;
+        }
+        $fullPath = $this->getAbsolutePath($path);
+
+        if ($fullPath === $defaultRoot) {
+            return true;
+        }
+
+        return (strlen($fullPath) > strlen($defaultRoot)) && (substr($fullPath, 0, strlen($defaultRoot) + 1) === $defaultRoot . '/');
+    }
+
+    /**
+     * @param string[] $hooks
+     * @param string $path
+     * @param bool $post
+     * @return bool
+     */
+    private function runHooks($hooks, $path, $post = false) {
+        $relativePath = $path;
+        $path = $this->getHookPath($path);
+        $prefix = $post ? 'post_' : '';
+        $run = true;
+        if ($this->shouldEmitHooks($relativePath)) {
+            foreach ($hooks as $hook) {
+                if ($hook != 'read') {
+                    \OC_Hook::emit(
+                        Filesystem::CLASSNAME,
+                        $prefix . $hook,
+                        array(
+                            Filesystem::signal_param_run => &$run,
+                            Filesystem::signal_param_path => $path
+                        )
+                    );
+                } elseif (!$post) {
+                    \OC_Hook::emit(
+                        Filesystem::CLASSNAME,
+                        $prefix . $hook,
+                        array(
+                            Filesystem::signal_param_path => $path
+                        )
+                    );
+                }
+            }
+        }
+        return $run;
+    }
+
+    /**
+     * check if a file or folder has been updated since $time
+     *
+     * @param string $path
+     * @param int $time
+     * @return bool
+     */
+    public function hasUpdated($path, $time) {
+        return $this->basicOperation('hasUpdated', $path, array(), $time);
+    }
+
+    /**
+     * @param string $ownerId
+     * @return \OC\User\User
+     */
+    private function getUserObjectForOwner($ownerId) {
+        $owner = $this->userManager->get($ownerId);
+        if ($owner instanceof IUser) {
+            return $owner;
+        } else {
+            return new User($ownerId, null, \OC::$server->getEventDispatcher());
+        }
+    }
+
+    /**
+     * Get file info from cache
+     *
+     * If the file is not in cached it will be scanned
+     * If the file has changed on storage the cache will be updated
+     *
+     * @param \OC\Files\Storage\Storage $storage
+     * @param string $internalPath
+     * @param string $relativePath
+     * @return ICacheEntry|bool
+     */
+    private function getCacheEntry($storage, $internalPath, $relativePath) {
+        $cache = $storage->getCache($internalPath);
+        $data = $cache->get($internalPath);
+        $watcher = $storage->getWatcher($internalPath);
+
+        try {
+            // if the file is not in the cache or needs to be updated, trigger the scanner and reload the data
+            if (!$data || $data['size'] === -1) {
+                if (!$storage->file_exists($internalPath)) {
+                    return false;
+                }
+                // don't need to get a lock here since the scanner does it's own locking
+                $scanner = $storage->getScanner($internalPath);
+                $scanner->scan($internalPath, Cache\Scanner::SCAN_SHALLOW);
+                $data = $cache->get($internalPath);
+            } else if (!Cache\Scanner::isPartialFile($internalPath) && $watcher->needsUpdate($internalPath, $data)) {
+                $this->lockFile($relativePath, ILockingProvider::LOCK_SHARED);
+                $watcher->update($internalPath, $data);
+                $storage->getPropagator()->propagateChange($internalPath, time());
+                $data = $cache->get($internalPath);
+                $this->unlockFile($relativePath, ILockingProvider::LOCK_SHARED);
+            }
+        } catch (LockedException $e) {
+            // if the file is locked we just use the old cache info
+        }
+
+        return $data;
+    }
+
+    /**
+     * get the filesystem info
+     *
+     * @param string $path
+     * @param boolean|string $includeMountPoints true to add mountpoint sizes,
+     * 'ext' to add only ext storage mount point sizes. Defaults to true.
+     * defaults to true
+     * @return \OC\Files\FileInfo|false False if file does not exist
+     */
+    public function getFileInfo($path, $includeMountPoints = true) {
+        $this->assertPathLength($path);
+        if (!Filesystem::isValidPath($path)) {
+            return false;
+        }
+        if (Cache\Scanner::isPartialFile($path)) {
+            return $this->getPartFileInfo($path);
+        }
+        $relativePath = $path;
+        $path = Filesystem::normalizePath($this->fakeRoot . '/' . $path);
+
+        $mount = Filesystem::getMountManager()->find($path);
+        if (!$mount) {
+            \OC::$server->getLogger()->warning('Mountpoint not found for path: ' . $path);
+            return false;
+        }
+        $storage = $mount->getStorage();
+        $internalPath = $mount->getInternalPath($path);
+        if ($storage) {
+            $data = $this->getCacheEntry($storage, $internalPath, $relativePath);
+
+            if (!$data instanceof ICacheEntry) {
+                return false;
+            }
+
+            if ($mount instanceof MoveableMount && $internalPath === '') {
+                $data['permissions'] |= \OCP\Constants::PERMISSION_DELETE;
+            }
+            $ownerId = $storage->getOwner($internalPath);
+            $owner = null;
+            if ($ownerId !== null) {
+                // ownerId might be null if files are accessed with an access token without file system access
+                $owner = $this->getUserObjectForOwner($ownerId);
+            }
+            $info = new FileInfo($path, $storage, $internalPath, $data, $mount, $owner);
+
+            if ($data and isset($data['fileid'])) {
+                if ($includeMountPoints and $data['mimetype'] === 'httpd/unix-directory') {
+                    //add the sizes of other mount points to the folder
+                    $extOnly = ($includeMountPoints === 'ext');
+                    $mounts = Filesystem::getMountManager()->findIn($path);
+                    $info->setSubMounts(array_filter($mounts, function (IMountPoint $mount) use ($extOnly) {
+                        $subStorage = $mount->getStorage();
+                        return !($extOnly && $subStorage instanceof \OCA\Files_Sharing\SharedStorage);
+                    }));
+                }
+            }
+
+            return $info;
+        } else {
+            \OC::$server->getLogger()->warning('Storage not valid for mountpoint: ' . $mount->getMountPoint());
+        }
+
+        return false;
+    }
+
+    /**
+     * get the content of a directory
+     *
+     * @param string $directory path under datadirectory
+     * @param string $mimetype_filter limit returned content to this mimetype or mimepart
+     * @return FileInfo[]
+     */
+    public function getDirectoryContent($directory, $mimetype_filter = '') {
+        $this->assertPathLength($directory);
+        if (!Filesystem::isValidPath($directory)) {
+            return [];
+        }
+        $path = $this->getAbsolutePath($directory);
+        $path = Filesystem::normalizePath($path);
+        $mount = $this->getMount($directory);
+        if (!$mount) {
+            return [];
+        }
+        $storage = $mount->getStorage();
+        $internalPath = $mount->getInternalPath($path);
+        if ($storage) {
+            $cache = $storage->getCache($internalPath);
+            $user = \OC_User::getUser();
+
+            $data = $this->getCacheEntry($storage, $internalPath, $directory);
+
+            if (!$data instanceof ICacheEntry || !isset($data['fileid']) || !($data->getPermissions() && Constants::PERMISSION_READ)) {
+                return [];
+            }
+
+            $folderId = $data['fileid'];
+            $contents = $cache->getFolderContentsById($folderId); //TODO: mimetype_filter
+
+            $sharingDisabled = \OCP\Util::isSharingDisabledForUser();
+
+            $fileNames = array_map(function(ICacheEntry $content) {
+                return $content->getName();
+            }, $contents);
+            /**
+             * @var \OC\Files\FileInfo[] $fileInfos
+             */
+            $fileInfos = array_map(function (ICacheEntry $content) use ($path, $storage, $mount, $sharingDisabled) {
+                if ($sharingDisabled) {
+                    $content['permissions'] = $content['permissions'] & ~\OCP\Constants::PERMISSION_SHARE;
+                }
+                $owner = $this->getUserObjectForOwner($storage->getOwner($content['path']));
+                return new FileInfo($path . '/' . $content['name'], $storage, $content['path'], $content, $mount, $owner);
+            }, $contents);
+            $files = array_combine($fileNames, $fileInfos);
+
+            //add a folder for any mountpoint in this directory and add the sizes of other mountpoints to the folders
+            $mounts = Filesystem::getMountManager()->findIn($path);
+            $dirLength = strlen($path);
+            foreach ($mounts as $mount) {
+                $mountPoint = $mount->getMountPoint();
+                $subStorage = $mount->getStorage();
+                if ($subStorage) {
+                    $subCache = $subStorage->getCache('');
+
+                    $rootEntry = $subCache->get('');
+                    if (!$rootEntry) {
+                        $subScanner = $subStorage->getScanner('');
+                        try {
+                            $subScanner->scanFile('');
+                        } catch (\OCP\Files\StorageNotAvailableException $e) {
+                            continue;
+                        } catch (\OCP\Files\StorageInvalidException $e) {
+                            continue;
+                        } catch (\Exception $e) {
+                            // sometimes when the storage is not available it can be any exception
+                            \OC::$server->getLogger()->logException($e, [
+                                'message' => 'Exception while scanning storage "' . $subStorage->getId() . '"',
+                                'level' => ILogger::ERROR,
+                                'app' => 'lib',
+                            ]);
+                            continue;
+                        }
+                        $rootEntry = $subCache->get('');
+                    }
+
+                    if ($rootEntry && ($rootEntry->getPermissions() && Constants::PERMISSION_READ)) {
+                        $relativePath = trim(substr($mountPoint, $dirLength), '/');
+                        if ($pos = strpos($relativePath, '/')) {
+                            //mountpoint inside subfolder add size to the correct folder
+                            $entryName = substr($relativePath, 0, $pos);
+                            foreach ($files as &$entry) {
+                                if ($entry->getName() === $entryName) {
+                                    $entry->addSubEntry($rootEntry, $mountPoint);
+                                }
+                            }
+                        } else { //mountpoint in this folder, add an entry for it
+                            $rootEntry['name'] = $relativePath;
+                            $rootEntry['type'] = $rootEntry['mimetype'] === 'httpd/unix-directory' ? 'dir' : 'file';
+                            $permissions = $rootEntry['permissions'];
+                            // do not allow renaming/deleting the mount point if they are not shared files/folders
+                            // for shared files/folders we use the permissions given by the owner
+                            if ($mount instanceof MoveableMount) {
+                                $rootEntry['permissions'] = $permissions | \OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE;
+                            } else {
+                                $rootEntry['permissions'] = $permissions & (\OCP\Constants::PERMISSION_ALL - (\OCP\Constants::PERMISSION_UPDATE | \OCP\Constants::PERMISSION_DELETE));
+                            }
+
+                            $rootEntry['path'] = substr(Filesystem::normalizePath($path . '/' . $rootEntry['name']), strlen($user) + 2); // full path without /$user/
+
+                            // if sharing was disabled for the user we remove the share permissions
+                            if (\OCP\Util::isSharingDisabledForUser()) {
+                                $rootEntry['permissions'] = $rootEntry['permissions'] & ~\OCP\Constants::PERMISSION_SHARE;
+                            }
+
+                            $owner = $this->getUserObjectForOwner($subStorage->getOwner(''));
+                            $files[$rootEntry->getName()] = new FileInfo($path . '/' . $rootEntry['name'], $subStorage, '', $rootEntry, $mount, $owner);
+                        }
+                    }
+                }
+            }
+
+            if ($mimetype_filter) {
+                $files = array_filter($files, function (FileInfo $file) use ($mimetype_filter) {
+                    if (strpos($mimetype_filter, '/')) {
+                        return $file->getMimetype() === $mimetype_filter;
+                    } else {
+                        return $file->getMimePart() === $mimetype_filter;
+                    }
+                });
+            }
+
+            return array_values($files);
+        } else {
+            return [];
+        }
+    }
+
+    /**
+     * change file metadata
+     *
+     * @param string $path
+     * @param array|\OCP\Files\FileInfo $data
+     * @return int
+     *
+     * returns the fileid of the updated file
+     */
+    public function putFileInfo($path, $data) {
+        $this->assertPathLength($path);
+        if ($data instanceof FileInfo) {
+            $data = $data->getData();
+        }
+        $path = Filesystem::normalizePath($this->fakeRoot . '/' . $path);
+        /**
+         * @var \OC\Files\Storage\Storage $storage
+         * @var string $internalPath
+         */
+        list($storage, $internalPath) = Filesystem::resolvePath($path);
+        if ($storage) {
+            $cache = $storage->getCache($path);
+
+            if (!$cache->inCache($internalPath)) {
+                $scanner = $storage->getScanner($internalPath);
+                $scanner->scan($internalPath, Cache\Scanner::SCAN_SHALLOW);
+            }
+
+            return $cache->put($internalPath, $data);
+        } else {
+            return -1;
+        }
+    }
+
+    /**
+     * search for files with the name matching $query
+     *
+     * @param string $query
+     * @return FileInfo[]
+     */
+    public function search($query) {
+        return $this->searchCommon('search', array('%' . $query . '%'));
+    }
+
+    /**
+     * search for files with the name matching $query
+     *
+     * @param string $query
+     * @return FileInfo[]
+     */
+    public function searchRaw($query) {
+        return $this->searchCommon('search', array($query));
+    }
+
+    /**
+     * search for files by mimetype
+     *
+     * @param string $mimetype
+     * @return FileInfo[]
+     */
+    public function searchByMime($mimetype) {
+        return $this->searchCommon('searchByMime', array($mimetype));
+    }
+
+    /**
+     * search for files by tag
+     *
+     * @param string|int $tag name or tag id
+     * @param string $userId owner of the tags
+     * @return FileInfo[]
+     */
+    public function searchByTag($tag, $userId) {
+        return $this->searchCommon('searchByTag', array($tag, $userId));
+    }
+
+    /**
+     * @param string $method cache method
+     * @param array $args
+     * @return FileInfo[]
+     */
+    private function searchCommon($method, $args) {
+        $files = array();
+        $rootLength = strlen($this->fakeRoot);
+
+        $mount = $this->getMount('');
+        $mountPoint = $mount->getMountPoint();
+        $storage = $mount->getStorage();
+        if ($storage) {
+            $cache = $storage->getCache('');
+
+            $results = call_user_func_array(array($cache, $method), $args);
+            foreach ($results as $result) {
+                if (substr($mountPoint . $result['path'], 0, $rootLength + 1) === $this->fakeRoot . '/') {
+                    $internalPath = $result['path'];
+                    $path = $mountPoint . $result['path'];
+                    $result['path'] = substr($mountPoint . $result['path'], $rootLength);
+                    $owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
+                    $files[] = new FileInfo($path, $storage, $internalPath, $result, $mount, $owner);
+                }
+            }
+
+            $mounts = Filesystem::getMountManager()->findIn($this->fakeRoot);
+            foreach ($mounts as $mount) {
+                $mountPoint = $mount->getMountPoint();
+                $storage = $mount->getStorage();
+                if ($storage) {
+                    $cache = $storage->getCache('');
+
+                    $relativeMountPoint = substr($mountPoint, $rootLength);
+                    $results = call_user_func_array(array($cache, $method), $args);
+                    if ($results) {
+                        foreach ($results as $result) {
+                            $internalPath = $result['path'];
+                            $result['path'] = rtrim($relativeMountPoint . $result['path'], '/');
+                            $path = rtrim($mountPoint . $internalPath, '/');
+                            $owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
+                            $files[] = new FileInfo($path, $storage, $internalPath, $result, $mount, $owner);
+                        }
+                    }
+                }
+            }
+        }
+        return $files;
+    }
+
+    /**
+     * Get the owner for a file or folder
+     *
+     * @param string $path
+     * @return string the user id of the owner
+     * @throws NotFoundException
+     */
+    public function getOwner($path) {
+        $info = $this->getFileInfo($path);
+        if (!$info) {
+            throw new NotFoundException($path . ' not found while trying to get owner');
+        }
+        return $info->getOwner()->getUID();
+    }
+
+    /**
+     * get the ETag for a file or folder
+     *
+     * @param string $path
+     * @return string
+     */
+    public function getETag($path) {
+        /**
+         * @var Storage\Storage $storage
+         * @var string $internalPath
+         */
+        list($storage, $internalPath) = $this->resolvePath($path);
+        if ($storage) {
+            return $storage->getETag($internalPath);
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Get the path of a file by id, relative to the view
+     *
+     * Note that the resulting path is not guarantied to be unique for the id, multiple paths can point to the same file
+     *
+     * @param int $id
+     * @throws NotFoundException
+     * @return string
+     */
+    public function getPath($id) {
+        $id = (int)$id;
+        $manager = Filesystem::getMountManager();
+        $mounts = $manager->findIn($this->fakeRoot);
+        $mounts[] = $manager->find($this->fakeRoot);
+        // reverse the array so we start with the storage this view is in
+        // which is the most likely to contain the file we're looking for
+        $mounts = array_reverse($mounts);
+
+        // put non shared mounts in front of the shared mount
+        // this prevent unneeded recursion into shares
+        usort($mounts, function(IMountPoint $a, IMountPoint $b) {
+            return $a instanceof SharedMount && (!$b instanceof SharedMount) ? 1 : -1;
+        });
+
+        foreach ($mounts as $mount) {
+            /**
+             * @var \OC\Files\Mount\MountPoint $mount
+             */
+            if ($mount->getStorage()) {
+                $cache = $mount->getStorage()->getCache();
+                $internalPath = $cache->getPathById($id);
+                if (is_string($internalPath)) {
+                    $fullPath = $mount->getMountPoint() . $internalPath;
+                    if (!is_null($path = $this->getRelativePath($fullPath))) {
+                        return $path;
+                    }
+                }
+            }
+        }
+        throw new NotFoundException(sprintf('File with id "%s" has not been found.', $id));
+    }
+
+    /**
+     * @param string $path
+     * @throws InvalidPathException
+     */
+    private function assertPathLength($path) {
+        $maxLen = min(PHP_MAXPATHLEN, 4000);
+        // Check for the string length - performed using isset() instead of strlen()
+        // because isset() is about 5x-40x faster.
+        if (isset($path[$maxLen])) {
+            $pathLen = strlen($path);
+            throw new \OCP\Files\InvalidPathException("Path length($pathLen) exceeds max path length($maxLen): $path");
+        }
+    }
+
+    /**
+     * check if it is allowed to move a mount point to a given target.
+     * It is not allowed to move a mount point into a different mount point or
+     * into an already shared folder
+     *
+     * @param IStorage $targetStorage
+     * @param string $targetInternalPath
+     * @return boolean
+     */
+    private function targetIsNotShared(IStorage $targetStorage, string $targetInternalPath) {
+
+        // note: cannot use the view because the target is already locked
+        $fileId = (int)$targetStorage->getCache()->getId($targetInternalPath);
+        if ($fileId === -1) {
+            // target might not exist, need to check parent instead
+            $fileId = (int)$targetStorage->getCache()->getId(dirname($targetInternalPath));
+        }
+
+        // check if any of the parents were shared by the current owner (include collections)
+        $shares = \OCP\Share::getItemShared(
+            'folder',
+            $fileId,
+            \OCP\Share::FORMAT_NONE,
+            null,
+            true
+        );
+
+        if (count($shares) > 0) {
+            \OCP\Util::writeLog('files',
+                'It is not allowed to move one mount point into a shared folder',
+                ILogger::DEBUG);
+            return false;
+        }
+
+        return true;
+    }
+
+    /**
+     * Get a fileinfo object for files that are ignored in the cache (part files)
+     *
+     * @param string $path
+     * @return \OCP\Files\FileInfo
+     */
+    private function getPartFileInfo($path) {
+        $mount = $this->getMount($path);
+        $storage = $mount->getStorage();
+        $internalPath = $mount->getInternalPath($this->getAbsolutePath($path));
+        $owner = \OC::$server->getUserManager()->get($storage->getOwner($internalPath));
+        return new FileInfo(
+            $this->getAbsolutePath($path),
+            $storage,
+            $internalPath,
+            [
+                'fileid' => null,
+                'mimetype' => $storage->getMimeType($internalPath),
+                'name' => basename($path),
+                'etag' => null,
+                'size' => $storage->filesize($internalPath),
+                'mtime' => $storage->filemtime($internalPath),
+                'encrypted' => false,
+                'permissions' => \OCP\Constants::PERMISSION_ALL
+            ],
+            $mount,
+            $owner
+        );
+    }
+
+    /**
+     * @param string $path
+     * @param string $fileName
+     * @throws InvalidPathException
+     */
+    public function verifyPath($path, $fileName) {
+        try {
+            /** @type \OCP\Files\Storage $storage */
+            list($storage, $internalPath) = $this->resolvePath($path);
+            $storage->verifyPath($internalPath, $fileName);
+        } catch (ReservedWordException $ex) {
+            $l = \OC::$server->getL10N('lib');
+            throw new InvalidPathException($l->t('File name is a reserved word'));
+        } catch (InvalidCharacterInPathException $ex) {
+            $l = \OC::$server->getL10N('lib');
+            throw new InvalidPathException($l->t('File name contains at least one invalid character'));
+        } catch (FileNameTooLongException $ex) {
+            $l = \OC::$server->getL10N('lib');
+            throw new InvalidPathException($l->t('File name is too long'));
+        } catch (InvalidDirectoryException $ex) {
+            $l = \OC::$server->getL10N('lib');
+            throw new InvalidPathException($l->t('Dot files are not allowed'));
+        } catch (EmptyFileNameException $ex) {
+            $l = \OC::$server->getL10N('lib');
+            throw new InvalidPathException($l->t('Empty filename is not allowed'));
+        }
+    }
+
+    /**
+     * get all parent folders of $path
+     *
+     * @param string $path
+     * @return string[]
+     */
+    private function getParents($path) {
+        $path = trim($path, '/');
+        if (!$path) {
+            return [];
+        }
+
+        $parts = explode('/', $path);
+
+        // remove the single file
+        array_pop($parts);
+        $result = array('/');
+        $resultPath = '';
+        foreach ($parts as $part) {
+            if ($part) {
+                $resultPath .= '/' . $part;
+                $result[] = $resultPath;
+            }
+        }
+        return $result;
+    }
+
+    /**
+     * Returns the mount point for which to lock
+     *
+     * @param string $absolutePath absolute path
+     * @param bool $useParentMount true to return parent mount instead of whatever
+     * is mounted directly on the given path, false otherwise
+     * @return \OC\Files\Mount\MountPoint mount point for which to apply locks
+     */
+    private function getMountForLock($absolutePath, $useParentMount = false) {
+        $results = [];
+        $mount = Filesystem::getMountManager()->find($absolutePath);
+        if (!$mount) {
+            return $results;
+        }
+
+        if ($useParentMount) {
+            // find out if something is mounted directly on the path
+            $internalPath = $mount->getInternalPath($absolutePath);
+            if ($internalPath === '') {
+                // resolve the parent mount instead
+                $mount = Filesystem::getMountManager()->find(dirname($absolutePath));
+            }
+        }
+
+        return $mount;
+    }
+
+    /**
+     * Lock the given path
+     *
+     * @param string $path the path of the file to lock, relative to the view
+     * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
+     * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
+     *
+     * @return bool False if the path is excluded from locking, true otherwise
+     * @throws \OCP\Lock\LockedException if the path is already locked
+     */
+    private function lockPath($path, $type, $lockMountPoint = false) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $absolutePath = Filesystem::normalizePath($absolutePath);
+        if (!$this->shouldLockFile($absolutePath)) {
+            return false;
+        }
+
+        $mount = $this->getMountForLock($absolutePath, $lockMountPoint);
+        if ($mount) {
+            try {
+                $storage = $mount->getStorage();
+                if ($storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
+                    $storage->acquireLock(
+                        $mount->getInternalPath($absolutePath),
+                        $type,
+                        $this->lockingProvider
+                    );
+                }
+            } catch (\OCP\Lock\LockedException $e) {
+                // rethrow with the a human-readable path
+                throw new \OCP\Lock\LockedException(
+                    $this->getPathRelativeToFiles($absolutePath),
+                    $e
+                );
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Change the lock type
+     *
+     * @param string $path the path of the file to lock, relative to the view
+     * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
+     * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
+     *
+     * @return bool False if the path is excluded from locking, true otherwise
+     * @throws \OCP\Lock\LockedException if the path is already locked
+     */
+    public function changeLock($path, $type, $lockMountPoint = false) {
+        $path = Filesystem::normalizePath($path);
+        $absolutePath = $this->getAbsolutePath($path);
+        $absolutePath = Filesystem::normalizePath($absolutePath);
+        if (!$this->shouldLockFile($absolutePath)) {
+            return false;
+        }
+
+        $mount = $this->getMountForLock($absolutePath, $lockMountPoint);
+        if ($mount) {
+            try {
+                $storage = $mount->getStorage();
+                if ($storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
+                    $storage->changeLock(
+                        $mount->getInternalPath($absolutePath),
+                        $type,
+                        $this->lockingProvider
+                    );
+                }
+            } catch (\OCP\Lock\LockedException $e) {
+                try {
+                    // rethrow with the a human-readable path
+                    throw new \OCP\Lock\LockedException(
+                        $this->getPathRelativeToFiles($absolutePath),
+                        $e
+                    );
+                } catch (\InvalidArgumentException $e) {
+                    throw new \OCP\Lock\LockedException(
+                        $absolutePath,
+                        $e
+                    );
+                }
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Unlock the given path
+     *
+     * @param string $path the path of the file to unlock, relative to the view
+     * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
+     * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
+     *
+     * @return bool False if the path is excluded from locking, true otherwise
+     */
+    private function unlockPath($path, $type, $lockMountPoint = false) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $absolutePath = Filesystem::normalizePath($absolutePath);
+        if (!$this->shouldLockFile($absolutePath)) {
+            return false;
+        }
+
+        $mount = $this->getMountForLock($absolutePath, $lockMountPoint);
+        if ($mount) {
+            $storage = $mount->getStorage();
+            if ($storage && $storage->instanceOfStorage('\OCP\Files\Storage\ILockingStorage')) {
+                $storage->releaseLock(
+                    $mount->getInternalPath($absolutePath),
+                    $type,
+                    $this->lockingProvider
+                );
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Lock a path and all its parents up to the root of the view
+     *
+     * @param string $path the path of the file to lock relative to the view
+     * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
+     * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
+     *
+     * @return bool False if the path is excluded from locking, true otherwise
+     */
+    public function lockFile($path, $type, $lockMountPoint = false) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $absolutePath = Filesystem::normalizePath($absolutePath);
+        if (!$this->shouldLockFile($absolutePath)) {
+            return false;
+        }
+
+        $this->lockPath($path, $type, $lockMountPoint);
+
+        $parents = $this->getParents($path);
+        foreach ($parents as $parent) {
+            $this->lockPath($parent, ILockingProvider::LOCK_SHARED);
+        }
+
+        return true;
+    }
+
+    /**
+     * Unlock a path and all its parents up to the root of the view
+     *
+     * @param string $path the path of the file to lock relative to the view
+     * @param int $type \OCP\Lock\ILockingProvider::LOCK_SHARED or \OCP\Lock\ILockingProvider::LOCK_EXCLUSIVE
+     * @param bool $lockMountPoint true to lock the mount point, false to lock the attached mount/storage
+     *
+     * @return bool False if the path is excluded from locking, true otherwise
+     */
+    public function unlockFile($path, $type, $lockMountPoint = false) {
+        $absolutePath = $this->getAbsolutePath($path);
+        $absolutePath = Filesystem::normalizePath($absolutePath);
+        if (!$this->shouldLockFile($absolutePath)) {
+            return false;
+        }
+
+        $this->unlockPath($path, $type, $lockMountPoint);
+
+        $parents = $this->getParents($path);
+        foreach ($parents as $parent) {
+            $this->unlockPath($parent, ILockingProvider::LOCK_SHARED);
+        }
+
+        return true;
+    }
+
+    /**
+     * Only lock files in data/user/files/
+     *
+     * @param string $path Absolute path to the file/folder we try to (un)lock
+     * @return bool
+     */
+    protected function shouldLockFile($path) {
+        $path = Filesystem::normalizePath($path);
+
+        $pathSegments = explode('/', $path);
+        if (isset($pathSegments[2])) {
+            // E.g.: /username/files/path-to-file
+            return ($pathSegments[2] === 'files') && (count($pathSegments) > 3);
+        }
+
+        return strpos($path, '/appdata_') !== 0;
+    }
+
+    /**
+     * Shortens the given absolute path to be relative to
+     * "$user/files".
+     *
+     * @param string $absolutePath absolute path which is under "files"
+     *
+     * @return string path relative to "files" with trimmed slashes or null
+     * if the path was NOT relative to files
+     *
+     * @throws \InvalidArgumentException if the given path was not under "files"
+     * @since 8.1.0
+     */
+    public function getPathRelativeToFiles($absolutePath) {
+        $path = Filesystem::normalizePath($absolutePath);
+        $parts = explode('/', trim($path, '/'), 3);
+        // "$user", "files", "path/to/dir"
+        if (!isset($parts[1]) || $parts[1] !== 'files') {
+            $this->logger->error(
+                '$absolutePath must be relative to "files", value is "%s"',
+                [
+                    $absolutePath
+                ]
+            );
+            throw new \InvalidArgumentException('$absolutePath must be relative to "files"');
+        }
+        if (isset($parts[2])) {
+            return $parts[2];
+        }
+        return '';
+    }
+
+    /**
+     * @param string $filename
+     * @return array
+     * @throws \OC\User\NoUserException
+     * @throws NotFoundException
+     */
+    public function getUidAndFilename($filename) {
+        $info = $this->getFileInfo($filename);
+        if (!$info instanceof \OCP\Files\FileInfo) {
+            throw new NotFoundException($this->getAbsolutePath($filename) . ' not found');
+        }
+        $uid = $info->getOwner()->getUID();
+        if ($uid != \OCP\User::getUser()) {
+            Filesystem::initMountPoints($uid);
+            $ownerView = new View('/' . $uid . '/files');
+            try {
+                $filename = $ownerView->getPath($info['fileid']);
+            } catch (NotFoundException $e) {
+                throw new NotFoundException('File with id ' . $info['fileid'] . ' not found for user ' . $uid);
+            }
+        }
+        return [$uid, $filename];
+    }
+
+    /**
+     * Creates parent non-existing folders
+     *
+     * @param string $filePath
+     * @return bool
+     */
+    private function createParentDirectories($filePath) {
+        $directoryParts = explode('/', $filePath);
+        $directoryParts = array_filter($directoryParts);
+        foreach ($directoryParts as $key => $part) {
+            $currentPathElements = array_slice($directoryParts, 0, $key);
+            $currentPath = '/' . implode('/', $currentPathElements);
+            if ($this->is_file($currentPath)) {
+                return false;
+            }
+            if (!$this->file_exists($currentPath)) {
+                $this->mkdir($currentPath);
+            }
+        }
+
+        return true;
+    }
 }