diff --git a/lib/files/storage/common.php b/lib/files/storage/common.php
index f9c6bdfce0c37f732c649fae7deebddb616c4832..cb41d17e446a12f523fd4bf40c04667d2f1e470f 100644
--- a/lib/files/storage/common.php
+++ b/lib/files/storage/common.php
@@ -22,81 +22,102 @@ namespace OC\Files\Storage;
 
 abstract class Common implements \OC\Files\Storage\Storage {
 
-	public function __construct($parameters) {}
+	public function __construct($parameters) {
+	}
+
 	public function is_dir($path) {
-		return $this->filetype($path)=='dir';
+		return $this->filetype($path) == 'dir';
 	}
+
 	public function is_file($path) {
-		return $this->filetype($path)=='file';
+		return $this->filetype($path) == 'file';
 	}
+
 	public function filesize($path) {
-		if($this->is_dir($path)) {
-			return 0;//by definition
-		}else{
+		if ($this->is_dir($path)) {
+			return 0; //by definition
+		} else {
 			$stat = $this->stat($path);
-			return $stat['size'];
+			if (isset($stat['size'])) {
+				return $stat['size'];
+			} else {
+				return 0;
+			}
 		}
 	}
+
 	public function isCreatable($path) {
 		if ($this->is_dir($path) && $this->isUpdatable($path)) {
 			return true;
 		}
 		return false;
 	}
+
 	public function isDeletable($path) {
 		return $this->isUpdatable($path);
 	}
+
 	public function isSharable($path) {
 		return $this->isReadable($path);
 	}
-	public function getPermissions($path){
+
+	public function getPermissions($path) {
 		$permissions = 0;
-		if($this->isCreatable($path)) {
+		if ($this->isCreatable($path)) {
 			$permissions |= \OCP\PERMISSION_CREATE;
 		}
-		if($this->isReadable($path)) {
+		if ($this->isReadable($path)) {
 			$permissions |= \OCP\PERMISSION_READ;
 		}
-		if($this->isUpdatable($path)) {
+		if ($this->isUpdatable($path)) {
 			$permissions |= \OCP\PERMISSION_UPDATE;
 		}
-		if($this->isDeletable($path)) {
+		if ($this->isDeletable($path)) {
 			$permissions |= \OCP\PERMISSION_DELETE;
 		}
-		if($this->isSharable($path)) {
+		if ($this->isSharable($path)) {
 			$permissions |= \OCP\PERMISSION_SHARE;
 		}
 		return $permissions;
 	}
+
 	public function filemtime($path) {
 		$stat = $this->stat($path);
-		return $stat['mtime'];
+		if (isset($stat['mtime'])) {
+			return $stat['mtime'];
+		} else {
+			return 0;
+		}
 	}
+
 	public function file_get_contents($path) {
 		$handle = $this->fopen($path, "r");
-		if(!$handle) {
+		if (!$handle) {
 			return false;
 		}
-		$size=$this->filesize($path);
-		if($size==0) {
+		$size = $this->filesize($path);
+		if ($size == 0) {
 			return '';
 		}
 		return fread($handle, $size);
 	}
+
 	public function file_put_contents($path, $data) {
 		$handle = $this->fopen($path, "w");
 		return fwrite($handle, $data);
 	}
+
 	public function rename($path1, $path2) {
-		if($this->copy($path1, $path2)) {
+		if ($this->copy($path1, $path2)) {
 			return $this->unlink($path1);
-		}else{
+		} else {
 			return false;
 		}
 	}
+
 	public function copy($path1, $path2) {
-		$source=$this->fopen($path1, 'r');
-		$target=$this->fopen($path2, 'w');
+		$source = $this->fopen($path1, 'r');
+		$target = $this->fopen($path2, 'w');
 		list($count, $result) = \OC_Helper::streamCopy($source, $target);
 		return $result;
 	}
@@ -110,29 +131,30 @@ abstract class Common implements \OC\Files\Storage\Storage {
 	 * @note By default the directory specified by $directory will be
 	 * deleted together with its contents. To avoid this set $empty to true
 	 */
-	public function deleteAll( $directory, $empty = false ) {
+	public function deleteAll($directory, $empty = false) {
 		$directory = trim($directory, '/');
 
-		if ( !$this->file_exists( \OCP\USER::getUser() . '/' . $directory )
-			|| !$this->is_dir( \OCP\USER::getUser() . '/' . $directory ) ) {
+		if (!$this->file_exists(\OCP\USER::getUser() . '/' . $directory)
+			|| !$this->is_dir(\OCP\USER::getUser() . '/' . $directory)
+		) {
 			return false;
-		} elseif( !$this->isReadable( \OCP\USER::getUser() . '/' . $directory ) ) {
+		} elseif (!$this->isReadable(\OCP\USER::getUser() . '/' . $directory)) {
 			return false;
 		} else {
-			$directoryHandle = $this->opendir( \OCP\USER::getUser() . '/' . $directory );
-			while ( $contents = readdir( $directoryHandle ) ) {
-				if ( $contents != '.' && $contents != '..') {
+			$directoryHandle = $this->opendir(\OCP\USER::getUser() . '/' . $directory);
+			while ($contents = readdir($directoryHandle)) {
+				if ($contents != '.' && $contents != '..') {
 					$path = $directory . "/" . $contents;
-					if ( $this->is_dir( $path ) ) {
-						$this->deleteAll( $path );
+					if ($this->is_dir($path)) {
+						$this->deleteAll($path);
 					} else {
-						$this->unlink( \OCP\USER::getUser() .'/' . $path ); // TODO: make unlink use same system path as is_dir
+						$this->unlink(\OCP\USER::getUser() . '/' . $path); // TODO: make unlink use same system path as is_dir
 					}
 				}
 			}
 			//$this->closedir( $directoryHandle ); // TODO: implement closedir in OC_FSV
-			if ( $empty == false ) {
-				if ( !$this->rmdir( $directory ) ) {
+			if ($empty == false) {
+				if (!$this->rmdir($directory)) {
 					return false;
 				}
 			}
@@ -140,88 +162,95 @@ abstract class Common implements \OC\Files\Storage\Storage {
 		}
 
 	}
+
 	public function getMimeType($path) {
-		if(!$this->file_exists($path)) {
+		if (!$this->file_exists($path)) {
 			return false;
 		}
-		if($this->is_dir($path)) {
+		if ($this->is_dir($path)) {
 			return 'httpd/unix-directory';
 		}
-		$source=$this->fopen($path, 'r');
-		if(!$source) {
+		$source = $this->fopen($path, 'r');
+		if (!$source) {
 			return false;
 		}
-		$head=fread($source, 8192);//8kb should suffice to determine a mimetype
-		if($pos=strrpos($path, '.')) {
-			$extension=substr($path, $pos);
-		}else{
-			$extension='';
+		$head = fread($source, 8192); //8kb should suffice to determine a mimetype
+		if ($pos = strrpos($path, '.')) {
+			$extension = substr($path, $pos);
+		} else {
+			$extension = '';
 		}
-		$tmpFile=\OC_Helper::tmpFile($extension);
+		$tmpFile = \OC_Helper::tmpFile($extension);
 		file_put_contents($tmpFile, $head);
-		$mime=\OC_Helper::getMimeType($tmpFile);
+		$mime = \OC_Helper::getMimeType($tmpFile);
 		unlink($tmpFile);
 		return $mime;
 	}
+
 	public function hash($type, $path, $raw = false) {
-		$tmpFile=$this->getLocalFile($path);
-		$hash=hash($type, $tmpFile, $raw);
+		$tmpFile = $this->getLocalFile($path);
+		$hash = hash($type, $tmpFile, $raw);
 		unlink($tmpFile);
 		return $hash;
 	}
+
 	public function search($query) {
 		return $this->searchInDir($query);
 	}
+
 	public function getLocalFile($path) {
 		return $this->toTmpFile($path);
 	}
-	private function toTmpFile($path) {//no longer in the storage api, still useful here
-		$source=$this->fopen($path, 'r');
-		if(!$source) {
+
+	private function toTmpFile($path) { //no longer in the storage api, still useful here
+		$source = $this->fopen($path, 'r');
+		if (!$source) {
 			return false;
 		}
-		if($pos=strrpos($path, '.')) {
-			$extension=substr($path, $pos);
-		}else{
-			$extension='';
+		if ($pos = strrpos($path, '.')) {
+			$extension = substr($path, $pos);
+		} else {
+			$extension = '';
 		}
-		$tmpFile=\OC_Helper::tmpFile($extension);
-		$target=fopen($tmpFile, 'w');
+		$tmpFile = \OC_Helper::tmpFile($extension);
+		$target = fopen($tmpFile, 'w');
 		\OC_Helper::streamCopy($source, $target);
 		return $tmpFile;
 	}
+
 	public function getLocalFolder($path) {
-		$baseDir=\OC_Helper::tmpFolder();
+		$baseDir = \OC_Helper::tmpFolder();
 		$this->addLocalFolder($path, $baseDir);
 		return $baseDir;
 	}
+
 	private function addLocalFolder($path, $target) {
-		if($dh=$this->opendir($path)) {
-			while($file=readdir($dh)) {
-				if($file!=='.' and $file!=='..') {
-					if($this->is_dir($path.'/'.$file)) {
-						mkdir($target.'/'.$file);
-						$this->addLocalFolder($path.'/'.$file, $target.'/'.$file);
-					}else{
-						$tmp=$this->toTmpFile($path.'/'.$file);
-						rename($tmp, $target.'/'.$file);
+		if ($dh = $this->opendir($path)) {
+			while ($file = readdir($dh)) {
+				if ($file !== '.' and $file !== '..') {
+					if ($this->is_dir($path . '/' . $file)) {
+						mkdir($target . '/' . $file);
+						$this->addLocalFolder($path . '/' . $file, $target . '/' . $file);
+					} else {
+						$tmp = $this->toTmpFile($path . '/' . $file);
+						rename($tmp, $target . '/' . $file);
 					}
 				}
 			}
 		}
 	}
 
-	protected function searchInDir($query, $dir='') {
-		$files=array();
-		$dh=$this->opendir($dir);
-		if($dh) {
-			while($item=readdir($dh)) {
+	protected function searchInDir($query, $dir = '') {
+		$files = array();
+		$dh = $this->opendir($dir);
+		if ($dh) {
+			while ($item = readdir($dh)) {
 				if ($item == '.' || $item == '..') continue;
-				if(strstr(strtolower($item), strtolower($query))!==false) {
-					$files[]=$dir.'/'.$item;
+				if (strstr(strtolower($item), strtolower($query)) !== false) {
+					$files[] = $dir . '/' . $item;
 				}
-				if($this->is_dir($dir.'/'.$item)) {
-					$files=array_merge($files, $this->searchInDir($query, $dir.'/'.$item));
+				if ($this->is_dir($dir . '/' . $item)) {
+					$files = array_merge($files, $this->searchInDir($query, $dir . '/' . $item));
 				}
 			}
 		}
@@ -230,32 +259,34 @@ abstract class Common implements \OC\Files\Storage\Storage {
 
 	/**
 	 * 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 $this->filemtime($path)>$time;
+		return $this->filemtime($path) > $time;
 	}
 
-	public function getCache($path=''){
+	public function getCache($path = '') {
 		return new \OC\Files\Cache\Cache($this);
 	}
 
-	public function getScanner($path=''){
+	public function getScanner($path = '') {
 		return new \OC\Files\Cache\Scanner($this);
 	}
 
-	public function getPermissionsCache($path=''){
+	public function getPermissionsCache($path = '') {
 		return new \OC\Files\Cache\Permissions($this);
 	}
 
-	public function getWatcher($path=''){
+	public function getWatcher($path = '') {
 		return new \OC\Files\Cache\Watcher($this);
 	}
 
 	/**
 	 * get the owner of a path
+	 *
 	 * @param string $path The path to get the owner
 	 * @return string uid or false
 	 */
@@ -269,12 +300,12 @@ abstract class Common implements \OC\Files\Storage\Storage {
 	 * @param string $path
 	 * @return string
 	 */
-	public function getETag($path){
+	public function getETag($path) {
 		$ETagFunction = \OC_Connector_Sabre_Node::$ETagFunction;
-		if($ETagFunction) {
+		if ($ETagFunction) {
 			$hash = call_user_func($ETagFunction, $path);
 			return $hash;
-		}else{
+		} else {
 			return uniqid();
 		}
 	}
@@ -282,6 +313,7 @@ abstract class Common implements \OC\Files\Storage\Storage {
 	/**
 	 * clean a path, i.e. remove all redundant '.' and '..'
 	 * making sure that it can't point to higher than '/'
+	 *
 	 * @param $path The path to clean
 	 * @return string cleaned path
 	 */
@@ -304,10 +336,11 @@ abstract class Common implements \OC\Files\Storage\Storage {
 
 	/**
 	 * get the free space in the storage
+	 *
 	 * @param $path
 	 * return int
 	 */
-	public function free_space($path){
+	public function free_space($path) {
 		return \OC\Files\FREE_SPACE_UNKNOWN;
 	}
 }