server/apps/files_external/lib/streamwrapper.php

<?php
/**
 * Copyright (c) 2012 Robin Appelman <icewind@owncloud.com>
 * This file is licensed under the Affero General Public License version 3 or
 * later.
 * See the COPYING-README file.
 */

namespace OC\Files\Storage;

abstract class StreamWrapper extends \OC\Files\Storage\Common{
	private $ready = false;

	protected function init(){
		if($this->ready){
			return;
		}
		$this->ready = true;

		//create the root folder if necesary
		if(!$this->is_dir('')) {
			$this->mkdir('');
		}
	}

	abstract public function constructUrl($path);

	public function mkdir($path) {
		$this->init();
		return mkdir($this->constructUrl($path));
	}

	public function rmdir($path) {
		$this->init();
		if($this->file_exists($path)) {
			$succes=rmdir($this->constructUrl($path));
			clearstatcache();
			return $succes;
		}else{
			return false;
		}
	}

	public function opendir($path) {
		$this->init();
		return opendir($this->constructUrl($path));
	}

	public function filetype($path) {
		$this->init();
		return filetype($this->constructUrl($path));
	}

	public function isReadable($path) {
		return true;//not properly supported
	}

	public function isUpdatable($path) {
		return true;//not properly supported
	}

	public function file_exists($path) {
		$this->init();
		return file_exists($this->constructUrl($path));
	}

	public function unlink($path) {
		$this->init();
		$succes=unlink($this->constructUrl($path));
		clearstatcache();
		return $succes;
	}

	public function fopen($path,$mode) {
		$this->init();
		return fopen($this->constructUrl($path),$mode);
	}

	public function free_space($path) {
		return 0;
	}

	public function touch($path,$mtime=null) {
		$this->init();
		if(is_null($mtime)) {
			$fh=$this->fopen($path,'a');
			fwrite($fh,'');
			fclose($fh);
		}else{
			return false;//not supported
		}
	}

	public function getFile($path,$target) {
		$this->init();
		return copy($this->constructUrl($path),$target);
	}

	public function uploadFile($path,$target) {
		$this->init();
		return copy($path,$this->constructUrl($target));
	}

	public function rename($path1,$path2) {
		$this->init();
		return rename($this->constructUrl($path1),$this->constructUrl($path2));
	}

	public function stat($path) {
		$this->init();
		return stat($this->constructUrl($path));
	}

}