server.php

很棒的在线教学系统

                echo "   <D:prop>\n";

                foreach ($file["noprops"] as $key => $prop) {
                    if ($prop["ns"] == "DAV:") {
                        echo "     <D:$prop[name]/>\n";
                    } else if ($prop["ns"] == "") {
                        echo "     <$prop[name] xmlns=\"\"/>\n";
                    } else {
                        echo "     <" . $ns_hash[$prop["ns"]] . ":$prop[name]/>\n";
                    }
                }

                echo "   </D:prop>\n";
                echo "   <D:status>HTTP/1.1 404 Not Found</D:status>\n";
                echo "  </D:propstat>\n";
            }
            
            echo " </D:response>\n";
        }
        
        echo "</D:multistatus>\n";
    }

    
    // }}}
    
    // {{{ http_PROPPATCH() 

    /**
     * PROPPATCH method handler
     *
     * @param  void
     * @return void
     */
    function http_PROPPATCH() 
    {
        if ($this->_check_lock_status($this->path)) {
            $options = Array();

            $options["path"] = $this->path;

            $propinfo = new _parse_proppatch("php://input");
            
            if (!$propinfo->success) {
                $this->http_status("400 Error");
                return;
            }
            
            $options['props'] = $propinfo->props;
            
            $responsedescr = $this->PROPPATCH($options);
            
            $this->http_status("207 Multi-Status");
            header('Content-Type: text/xml; charset="utf-8"');
            
            echo "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";

            echo "<D:multistatus xmlns:D=\"DAV:\">\n";
            echo " <D:response>\n";
            echo "  <D:href>".$this->_urlencode($this->_mergePathes($this->_SERVER["SCRIPT_NAME"], $this->path))."</D:href>\n";

            foreach ($options["props"] as $prop) {
                echo "   <D:propstat>\n";
                echo "    <D:prop><$prop[name] xmlns=\"$prop[ns]\"/></D:prop>\n";
                echo "    <D:status>HTTP/1.1 $prop[status]</D:status>\n";
                echo "   </D:propstat>\n";
            }

            if ($responsedescr) {
                echo "  <D:responsedescription>".
                    $this->_prop_encode(htmlspecialchars($responsedescr)).
                    "</D:responsedescription>\n";
            }

            echo " </D:response>\n";
            echo "</D:multistatus>\n";
        } else {
            $this->http_status("423 Locked");
        }
    }
    
    // }}}


    // {{{ http_MKCOL() 

    /**
     * MKCOL method handler
     *
     * @param  void
     * @return void
     */
    function http_MKCOL() 
    {
        $options = Array();

        $options["path"] = $this->path;

        $stat = $this->MKCOL($options);

        $this->http_status($stat);
    }

    // }}}


    // {{{ http_GET() 

    /**
     * GET method handler
     *
     * @param void
     * @returns void
     */
    function http_GET() 
    {
        // TODO check for invalid stream
        $options         = Array();
        $options["path"] = $this->path;

        $this->_get_ranges($options);

        if (true === ($status = $this->GET($options))) {
            if (!headers_sent()) {
                $status = "200 OK";

                if (!isset($options['mimetype'])) {
                    $options['mimetype'] = "application/octet-stream";
                }
                header("Content-type: $options[mimetype]");
                
                if (isset($options['mtime'])) {
                    header("Last-modified:".gmdate("D, d M Y H:i:s ", $options['mtime'])."GMT");
                }
                
                if (isset($options['stream'])) {
                    // GET handler returned a stream
                    if (!empty($options['ranges']) && (0===fseek($options['stream'], 0, SEEK_SET))) {
                        // partial request and stream is seekable 
                        
                        if (count($options['ranges']) === 1) {
                            $range = $options['ranges'][0];
                            
                            if (isset($range['start'])) {
                                fseek($options['stream'], $range['start'], SEEK_SET);
                                if (feof($options['stream'])) {
                                    $this->http_status("416 Requested range not satisfiable");
                                    return;
                                }

                                if (isset($range['end'])) {
                                    $size = $range['end']-$range['start']+1;
                                    $this->http_status("206 partial");
                                    header("Content-length: $size");
                                    header("Content-range: $range[start]-$range[end]/"
                                           . (isset($options['size']) ? $options['size'] : "*"));
                                    while ($size && !feof($options['stream'])) {
                                        $buffer = fread($options['stream'], 4096);
                                        $size  -= $this->bytes($buffer);
                                        echo $buffer;
                                    }
                                } else {
                                    $this->http_status("206 partial");
                                    if (isset($options['size'])) {
                                        header("Content-length: ".($options['size'] - $range['start']));
                                        header("Content-range: ".$range['start']."-".$range['end']."/"
                                               . (isset($options['size']) ? $options['size'] : "*"));
                                    }
                                    fpassthru($options['stream']);
                                }
                            } else {
                                header("Content-length: ".$range['last']);
                                fseek($options['stream'], -$range['last'], SEEK_END);
                                fpassthru($options['stream']);
                            }
                        } else {
                            $this->_multipart_byterange_header(); // init multipart
                            foreach ($options['ranges'] as $range) {
                                // TODO what if size unknown? 500?
                                if (isset($range['start'])) {
                                    $from = $range['start'];
                                    $to   = !empty($range['end']) ? $range['end'] : $options['size']-1; 
                                } else {
                                    $from = $options['size'] - $range['last']-1;
                                    $to   = $options['size'] -1;
                                }
                                $total = isset($options['size']) ? $options['size'] : "*"; 
                                $size  = $to - $from + 1;
                                $this->_multipart_byterange_header($options['mimetype'], $from, $to, $total);


                                fseek($options['stream'], $from, SEEK_SET);
                                while ($size && !feof($options['stream'])) {
                                    $buffer = fread($options['stream'], 4096);
                                    $size  -= $this->bytes($buffer);
                                    echo $buffer;
                                }
                            }
                            $this->_multipart_byterange_header(); // end multipart
                        }
                    } else {
                        // normal request or stream isn't seekable, return full content
                        if (isset($options['size'])) {
                            header("Content-length: ".$options['size']);
                        }
                        fpassthru($options['stream']);
                        return; // no more headers
                    }
                } elseif (isset($options['data'])) {
                    if (is_array($options['data'])) {
                        // reply to partial request
                    } else {
                        header("Content-length: ".$this->bytes($options['data']));
                        echo $options['data'];
                    }
                }
            } 
        } 

        if (!headers_sent()) {
            if (false === $status) {
                $this->http_status("404 not found");
            } else {
                // TODO: check setting of headers in various code pathes above
                $this->http_status("$status");
            }
        }
    }


    /**
     * parse HTTP Range: header
     *
     * @param  array options array to store result in
     * @return void
     */
    function _get_ranges(&$options) 
    {
        // process Range: header if present
        if (isset($this->_SERVER['HTTP_RANGE'])) {

            // we only support standard "bytes" range specifications for now
            if (preg_match('/bytes\s*=\s*(.+)/', $this->_SERVER['HTTP_RANGE'], $matches)) {
                $options["ranges"] = array();

                // ranges are comma separated
                foreach (explode(",", $matches[1]) as $range) {
                    // ranges are either from-to pairs or just end positions
                    list($start, $end) = explode("-", $range);
                    $options["ranges"][] = ($start==="") 
                        ? array("last"=>$end) 
                        : array("start"=>$start, "end"=>$end);
                }
            }
        }
    }

    /**
     * generate separator headers for multipart response
     *
     * first and last call happen without parameters to generate 
     * the initial header and closing sequence, all calls inbetween
     * require content mimetype, start and end byte position and
     * optionaly the total byte length of the requested resource
     *
     * @param  string  mimetype
     * @param  int     start byte position
     * @param  int     end   byte position
     * @param  int     total resource byte size
     */
    function _multipart_byterange_header($mimetype = false, $from = false, $to=false, $total=false) 
    {
        if ($mimetype === false) {
            if (!isset($this->multipart_separator)) {
                // initial

                // a little naive, this sequence *might* be part of the content
                // but it's really not likely and rather expensive to check 
                $this->multipart_separator = "SEPARATOR_".md5(microtime());

                // generate HTTP header
                header("Content-type: multipart/byteranges; boundary=".$this->multipart_separator);
            } else {
                // final 

                // generate closing multipart sequence
                echo "\n--{$this->multipart_separator}--";
            }
        } else {
            // generate separator and header for next part
            echo "\n--{$this->multipart_separator}\n";
            echo "Content-type: $mimetype\n";
            echo "Content-range: $from-$to/". ($total === false ? "*" : $total);
            echo "\n\n";
        }
    }

            

    // }}}

    // {{{ http_HEAD() 

    /**
     * HEAD method handler
     *
     * @param  void
     * @return void
     */
    function http_HEAD() 
    {
        $status          = false;
        $options         = Array();
        $options["path"] = $this->path;
        
        if (method_exists($this, "HEAD")) {
            $status = $this->head($options);
        } else if (method_exists($this, "GET")) {
            ob_start();
            $status = $this->GET($options);
            if (!isset($options['size'])) {
                $options['size'] = ob_get_length();
            }
            ob_end_clean();
        }
        
        if (!isset($options['mimetype'])) {
            $options['mimetype'] = "application/octet-stream";
        }
        header("Content-type: $options[mimetype]");
        
        if (isset($options['mtime'])) {
            header("Last-modified:".gmdate("D, d M Y H:i:s ", $options['mtime'])."GMT");
        }
                
        if (isset($options['size'])) {
            header("Content-length: ".$options['size']);
        }

        if ($status === true)  $status = "200 OK";
        if ($status === false) $status = "404 Not found";
        
        $this->http_status($status);
    }

    // }}}

    // {{{ http_PUT() 

    /**
     * PUT method handler
     *
     * @param  void
     * @return void
     */
    function http_PUT() 
    {
        if ($this->_check_lock_status($this->path)) {
            $options                   = Array();
            $options["path"]           = $this->path;
            $options["content_length"] = $this->_SERVER["CONTENT_LENGTH"];

            // get the Content-type 
            if (isset($this->_SERVER["CONTENT_TYPE"])) {
                // for now we do not support any sort of multipart requests
                if (!strncmp($this->_SERVER["CONTENT_TYPE"], "multipart/", 10)) {
                    $this->http_status("501 not implemented");
                    echo "The service does not support mulipart PUT requests";
                    return;
                }
                $options["content_type"] = $this->_SERVER["CONTENT_TYPE"];
            } else {
                // default content type if none given
                $options["content_type"] = "application/octet-stream";
            }

            /* RFC 2616 2.6 says: "The recipient of the entity MUST NOT 
             ignore any Content-* (e.g. Content-Range) headers that it 
             does not understand or implement and MUST return a 501 
             (Not Implemented) response in such cases."
            */ 
            foreach ($this->_SERVER as $key => $val) {
                if (strncmp($key, "HTTP_CONTENT", 11)) continue;
                switch ($key) {
                case 'HTTP_CONTENT_ENCODING': // RFC 2616 14.11
                    // TODO support this if ext/zlib filters are available
                    $this->http_status("501 not implemented"); 
                    echo "The service does not support '$val' content encoding";
                    return;

                case 'HTTP_CONTENT_LANGUAGE': // RFC 2616 14.12
                    // we assume it is not critical if this one is ignored
                    // in the actual PUT implementation ...
                    $options["content_language"] = $val;
                    break;

                case 'HTTP_CONTENT_LOCATION': // RFC 2616 14.14
                    /* The meaning of the Content-Location header in PUT 
                     or POST requests is undefined; servers are free 
                     to ignore it in those cases. */
                    break;