* (bug 24563) Entries on Special:WhatLinksHere now have a link to their history
[lhc/web/wiklou.git] / includes / HttpFunctions.php
index 35874e8..9464895 100644 (file)
@@ -8,20 +8,38 @@
  * @ingroup HTTP
  */
 class Http {
+       static $httpEngine = false;
+
        /**
         * Perform an HTTP request
-        * @param $method string HTTP method. Usually GET/POST
-        * @param $url string Full URL to act on
-        * @param $opts options to pass to HttpRequest object
-        * @returns mixed (bool)false on failure or a string on success
-        */
-       public static function request( $method, $url, $opts = array() ) {
-               $opts['method'] = strtoupper( $method );
-               if ( !array_key_exists( 'timeout', $opts ) ) {
-                       $opts['timeout'] = 'default';
-               }
-               $req = HttpRequest::factory( $url, $opts );
-               $status = $req->doRequest();
+        *
+        * @param $method String: HTTP method. Usually GET/POST
+        * @param $url String: full URL to act on
+        * @param $options Array: options to pass to HttpRequest object.
+        *      Possible keys for the array:
+        *    - timeout             Timeout length in seconds
+        *    - postData            An array of key-value pairs or a url-encoded form data
+        *    - proxy               The proxy to use.
+        *                          Will use $wgHTTPProxy (if set) otherwise.
+        *    - noProxy             Override $wgHTTPProxy (if set) and don't use any proxy at all.
+        *    - sslVerifyHost       (curl only) Verify hostname against certificate
+        *    - sslVerifyCert       (curl only) Verify SSL certificate
+        *    - caInfo              (curl only) Provide CA information
+        *    - maxRedirects        Maximum number of redirects to follow (defaults to 5)
+        *    - followRedirects     Whether to follow redirects (defaults to false). 
+        *                                  Note: this should only be used when the target URL is trusted,
+        *                                  to avoid attacks on intranet services accessible by HTTP.
+        * @return Mixed: (bool)false on failure or a string on success
+        */
+       public static function request( $method, $url, $options = array() ) {
+               $url = wfExpandUrl( $url );
+               wfDebug( "HTTP: $method: $url\n" );
+               $options['method'] = strtoupper( $method );
+               if ( !isset( $options['timeout'] ) ) {
+                       $options['timeout'] = 'default';
+               }
+               $req = HttpRequest::factory( $url, $options );
+               $status = $req->execute();
                if ( $status->isOK() ) {
                        return $req->getContent();
                } else {
@@ -33,23 +51,24 @@ class Http {
         * Simple wrapper for Http::request( 'GET' )
         * @see Http::request()
         */
-       public static function get( $url, $timeout = 'default', $opts = array() ) {
-               $opts['timeout'] = $timeout;
-               return Http::request( 'GET', $url, $opts );
+       public static function get( $url, $timeout = 'default', $options = array() ) {
+               $options['timeout'] = $timeout;
+               return Http::request( 'GET', $url, $options );
        }
 
        /**
         * Simple wrapper for Http::request( 'POST' )
         * @see Http::request()
         */
-       public static function post( $url, $opts = array() ) {
-               return Http::request( 'POST', $url, $opts );
+       public static function post( $url, $options = array() ) {
+               return Http::request( 'POST', $url, $options );
        }
 
        /**
         * Check if the URL can be served by localhost
-        * @param $url string Full url to check
-        * @return bool
+        *
+        * @param $url String: full url to check
+        * @return Boolean
         */
        public static function isLocalURL( $url ) {
                global $wgCommandLineMode, $wgConf;
@@ -82,7 +101,7 @@ class Http {
 
        /**
         * A standard user-agent we can use for external requests.
-        * @returns string
+        * @return String
         */
        public static function userAgent() {
                global $wgVersion;
@@ -91,8 +110,9 @@ class Http {
 
        /**
         * Checks that the given URI is a valid one
+        *
         * @param $uri Mixed: URI to check for validity
-        * @returns bool
+        * @returns Boolean
         */
        public static function isValidURI( $uri ) {
                return preg_match(
@@ -101,728 +121,842 @@ class Http {
                        $matches
                );
        }
+}
+
+/**
+ * This wrapper class will call out to curl (if available) or fallback
+ * to regular PHP if necessary for handling internal HTTP requests.
+ */
+class HttpRequest {
+       protected $content;
+       protected $timeout = 'default';
+       protected $headersOnly = null;
+       protected $postData = null;
+       protected $proxy = null;
+       protected $noProxy = false;
+       protected $sslVerifyHost = true;
+       protected $sslVerifyCert = true;
+       protected $caInfo = null;
+       protected $method = "GET";
+       protected $reqHeaders = array();
+       protected $url;
+       protected $parsedUrl;
+       protected $callback;
+       protected $maxRedirects = 5;
+       protected $followRedirects = false;
+
+       protected $cookieJar;
+
+       protected $headerList = array();
+       protected $respVersion = "0.9";
+       protected $respStatus = "200 Ok";
+       protected $respHeaders = array();
+
+       public $status;
+
        /**
-        * Fetch a URL, write the result to a file.
-        * @params $url string url to fetch
-        * @params $targetFilePath string full path (including filename) to write the file to
-        * @params $async bool whether the download should be asynchronous (defaults to false)
-        * @params $redirectCount int used internally to keep track of the number of redirects
-        *
-        * @returns Status -- for async requests this will contain the request key
+        * @param $url String: url to use
+        * @param $options Array: (optional) extra params to pass (see Http::request())
         */
-       public static function doDownload( $url, $targetFilePath, $async = false, $redirectCount = 0 ) {
-               global $wgPhpCli, $wgMaxUploadSize, $wgMaxRedirects;
+       function __construct( $url, $options = array() ) {
+               global $wgHTTPTimeout;
 
-               // do a quick check to HEAD to insure the file size is not > $wgMaxUploadSize
-               $headRequest = HttpRequest::factory( $url, array( 'headersOnly' => true ) );
-               $headResponse = $headRequest->doRequest();
-               if ( !$headResponse->isOK() ) {
-                       return $headResponse;
-               }
-               $head = $headResponse->value;
+               $this->url = $url;
+               $this->parsedUrl = parse_url( $url );
 
-               // check for redirects:
-               if ( $redirectCount < 0 ) {
-                       $redirectCount = 0;
-               }
-               if ( isset( $head['Location'] ) && strrpos( $head[0], '302' ) !== false ) {
-                       if ( $redirectCount < $wgMaxRedirects ) {
-                               if ( self::isValidURI( $head['Location'] ) ) {
-                                       return self::doDownload( $head['Location'], $targetFilePath,
-                                                                                        $async, $redirectCount++ );
-                               } else {
-                                       return Status::newFatal( 'upload-proto-error' );
-                               }
-                       } else {
-                               return Status::newFatal( 'upload-too-many-redirects' );
-                       }
+               if ( !Http::isValidURI( $this->url ) ) {
+                       $this->status = Status::newFatal('http-invalid-url');
+               } else {
+                       $this->status = Status::newGood( 100 ); // continue
                }
-               // we did not get a 200 ok response:
-               if ( strrpos( $head[0], '200 OK' ) === false ) {
-                       return Status::newFatal( 'upload-http-error', htmlspecialchars( $head[0] ) );
+
+               if ( isset($options['timeout']) && $options['timeout'] != 'default' ) {
+                       $this->timeout = $options['timeout'];
+               } else {
+                       $this->timeout = $wgHTTPTimeout;
                }
 
-               $contentLength = $head['Content-Length'];
-               if ( $contentLength ) {
-                       if ( $contentLength > $wgMaxUploadSize ) {
-                               return Status::newFatal( 'requested file length ' . $contentLength .
-                                                                                ' is greater than $wgMaxUploadSize: ' . $wgMaxUploadSize );
+               $members = array( "postData", "proxy", "noProxy", "sslVerifyHost", "caInfo",
+                                 "method", "followRedirects", "maxRedirects", "sslVerifyCert" );
+               foreach ( $members as $o ) {
+                       if ( isset($options[$o]) ) {
+                               $this->$o = $options[$o];
                        }
                }
+       }
 
-               // check if we can find phpCliPath (for doing a background shell request to
-               // php to do the download:
-               if ( $async && $wgPhpCli && wfShellExecEnabled() ) {
-                       wfDebug( __METHOD__ . "\nASYNC_DOWNLOAD\n" );
-                       // setup session and shell call:
-                       return self::startBackgroundRequest( $url, $targetFilePath, $contentLength );
-               } else {
-                       wfDebug( __METHOD__ . "\nSYNC_DOWNLOAD\n" );
-                       // SYNC_DOWNLOAD download as much as we can in the time we have to execute
-                       $opts['method'] = 'GET';
-                       $opts['targetFilePath'] = $mTargetFilePath;
-                       $req = HttpRequest::factory( $url, $opts );
-                       return $req->doRequest();
+       /**
+        * Generate a new request object
+        * @see HttpRequest::__construct
+        */
+       public static function factory( $url, $options = null ) {
+               if ( !Http::$httpEngine ) {
+                       Http::$httpEngine = function_exists( 'curl_init' ) ? 'curl' : 'php';
+               } elseif ( Http::$httpEngine == 'curl' && !function_exists( 'curl_init' ) ) {
+                       throw new MWException( __METHOD__.': curl (http://php.net/curl) is not installed, but'.
+                                                                  ' Http::$httpEngine is set to "curl"' );
+               }
+
+               switch( Http::$httpEngine ) {
+               case 'curl':
+                       return new CurlHttpRequest( $url, $options );
+               case 'php':
+                       if ( !wfIniGetBool( 'allow_url_fopen' ) ) {
+                               throw new MWException( __METHOD__.': allow_url_fopen needs to be enabled for pure PHP'.
+                                       ' http requests to work. If possible, curl should be used instead. See http://php.net/curl.' );
+                       }
+                       return new PhpHttpRequest( $url, $options );
+               default:
+                       throw new MWException( __METHOD__.': The setting of Http::$httpEngine is not valid.' );
                }
        }
 
        /**
-        * Start backgrounded (i.e. non blocking) request.      The
-        * backgrounded request will provide updates to the user's session
-        * data.
-        * @param $url string the URL to download
-        * @param $targetFilePath string the destination for the downloaded file
-        * @param $contentLength int (optional) the length of the download from the HTTP header
+        * Get the body, or content, of the response to the request
         *
-        * @returns Status
+        * @return String
         */
-       private static function startBackgroundRequest( $url, $targetFilePath, $contentLength = null ) {
-               global $IP, $wgPhpCli, $wgServer;
-               $status = Status::newGood();
+       public function getContent() {
+               return $this->content;
+       }
 
-               // generate a session id with all the details for the download (pid, targetFilePath )
-               $requestKey = self::createRequestKey();
-               $sessionID = session_id();
+       /**
+        * Set the parameters of the request
+        
+        * @param $args Array
+        * @todo overload the args param
+        */
+       public function setData($args) {
+               $this->postData = $args;
+       }
 
-               // store the url and target path:
-               $_SESSION['wsBgRequest'][$requestKey]['url'] = $url;
-               $_SESSION['wsBgRequest'][$requestKey]['targetFilePath'] = $targetFilePath;
-               // since we request from the cmd line we lose the original host name pass in the session:
-               $_SESSION['wsBgRequest'][$requestKey]['orgServer'] = $wgServer;
+       /**
+        * Take care of setting up the proxy
+        * (override in subclass)
+        *
+        * @return String
+        */
+       public function proxySetup() {
+               global $wgHTTPProxy;
 
-               if ( $contentLength ) {
-                       $_SESSION['wsBgRequest'][$requestKey]['contentLength'] = $contentLength;
+               if ( $this->proxy ) {
+                       return;
                }
+               if ( Http::isLocalURL( $this->url ) ) {
+                       $this->proxy = 'http://localhost:80/';
+               } elseif ( $wgHTTPProxy ) {
+                       $this->proxy = $wgHTTPProxy ;
+               } elseif ( getenv( "http_proxy" ) ) {
+                       $this->proxy = getenv( "http_proxy" );
+               }
+       }
 
-               // set initial loaded bytes:
-               $_SESSION['wsBgRequest'][$requestKey]['loaded'] = 0;
-
-               // run the background download request:
-               $cmd = $wgPhpCli . ' ' . $IP . "/maintenance/httpSessionDownload.php " .
-                       "--sid {$sessionID} --usk {$requestKey} --wiki " . wfWikiId();
-               $pid = wfShellBackgroundExec( $cmd );
-               // the pid is not of much use since we won't be visiting this same apache any-time soon.
-               if ( !$pid )
-                       return Status::newFatal( 'http-could-not-background' );
-
-               // update the status value with the $requestKey (for the user to
-               // check on the status of the download)
-               $status->value = $requestKey;
+       /**
+        * Set the refererer header
+        */
+       public function setReferer( $url ) {
+               $this->setHeader('Referer', $url);
+       }
 
-               // return good status
-               return $status;
+       /**
+        * Set the user agent
+        */
+       public function setUserAgent( $UA ) {
+               $this->setHeader('User-Agent', $UA);
        }
 
        /**
-        * Returns a unique, random string that can be used as an request key and
-        * preloads it into the session data.
-        *
-        * @returns string
+        * Set an arbitrary header
         */
-       static function createRequestKey() {
-               if ( !array_key_exists( 'wsBgRequest', $_SESSION ) ) {
-                       $_SESSION['wsBgRequest'] = array();
-               }
+       public function setHeader($name, $value) {
+               // I feel like I should normalize the case here...
+               $this->reqHeaders[$name] = $value;
+       }
 
-               $key = uniqid( 'bgrequest', true );
+       /**
+        * Get an array of the headers
+        */
+       public function getHeaderList() {
+               $list = array();
 
-               // This is probably over-defensive.
-               while ( array_key_exists( $key, $_SESSION['wsBgRequest'] ) ) {
-                       $key = uniqid( 'bgrequest', true );
+               if( $this->cookieJar ) {
+                       $this->reqHeaders['Cookie'] =
+                               $this->cookieJar->serializeToHttpRequest($this->parsedUrl['path'],
+                                                                                                                $this->parsedUrl['host']);
+               }
+               foreach($this->reqHeaders as $name => $value) {
+                       $list[] = "$name: $value";
                }
-               $_SESSION['wsBgRequest'][$key] = array();
+               return $list;
+       }
 
-               return $key;
+       /**
+        * Set the callback
+        *
+        * @param $callback Callback
+        */
+       public function setCallback( $callback ) {
+               $this->callback = $callback;
        }
 
        /**
-        * Recover the necessary session and request information
-        * @param $sessionID string
-        * @param $requestKey string the HTTP request key
+        * A generic callback to read the body of the response from a remote
+        * server.
         *
-        * @returns array request information
+        * @param $fh handle
+        * @param $content String
         */
-       private static function recoverSession( $sessionID, $requestKey ) {
-               global $wgUser, $wgServer, $wgSessionsInMemcached;
+       public function read( $fh, $content ) {
+               $this->content .= $content;
+               return strlen( $content );
+       }
 
-               // set session to the provided key:
-               session_id( $sessionID );
-               // fire up mediaWiki session system:
-               wfSetupSession();
+       /**
+        * Take care of whatever is necessary to perform the URI request.
+        *
+        * @return Status
+        */
+       public function execute() {
+               global $wgTitle;
 
-               // start the session
-               if ( session_start() === false ) {
-                       wfDebug( __METHOD__ . ' could not start session' );
+               $this->content = "";
+
+               if( strtoupper($this->method) == "HEAD" ) {
+                       $this->headersOnly = true;
                }
-               // get all the vars we need from session_id
-               if ( !isset( $_SESSION[ 'wsBgRequest' ][ $requestKey ] ) ) {
-                       wfDebug(        __METHOD__ . ' Error:could not find upload session' );
-                       exit();
+
+               if ( is_array( $this->postData ) ) {
+                       $this->postData = wfArrayToCGI( $this->postData );
                }
-               // setup the global user from the session key we just inherited
-               $wgUser = User::newFromSession();
 
-               // grab the session data to setup the request:
-               $sd =& $_SESSION['wsBgRequest'][$requestKey];
+               if ( is_object( $wgTitle ) && !isset($this->reqHeaders['Referer']) ) {
+                       $this->setReferer( $wgTitle->getFullURL() );
+               }
 
-               // update the wgServer var ( since cmd line thinks we are localhost
-               // when we are really orgServer)
-               if ( isset( $sd['orgServer'] ) && $sd['orgServer'] ) {
-                       $wgServer = $sd['orgServer'];
+               if ( !$this->noProxy ) {
+                       $this->proxySetup();
                }
-               // close down the session so we can other http queries can get session
-               // updates: (if not $wgSessionsInMemcached)
-               if ( !$wgSessionsInMemcached ) {
-                       session_write_close();
+
+               if ( !$this->callback ) {
+                       $this->setCallback( array( $this, 'read' ) );
                }
 
-               return $sd;
+               if ( !isset($this->reqHeaders['User-Agent']) ) {
+                       $this->setUserAgent(Http::userAgent());
+               }
        }
 
        /**
-        * Update the session with the finished information.
-        * @param $sessionID string
-        * @param $requestKey string the HTTP request key
+        * Parses the headers, including the HTTP status code and any
+        * Set-Cookie headers.  This function expectes the headers to be
+        * found in an array in the member variable headerList.
+        *
+        * @return nothing
         */
-       private static function updateSession( $sessionID, $requestKey, $status ) {
-
-               if ( session_start() === false ) {
-                       wfDebug( __METHOD__ . ' ERROR:: Could not start session' );
-               }
-
-               $sd =& $_SESSION['wsBgRequest'][$requestKey];
-               if ( !$status->isOK() ) {
-                       $sd['apiUploadResult'] = FormatJson::encode(
-                               array( 'error' => $status->getWikiText() )
-                       );
-               } else {
-                       $sd['apiUploadResult'] = FormatJson::encode( $status->value );
+       protected function parseHeader() {
+               $lastname = "";
+               foreach( $this->headerList as $header ) {
+                       if( preg_match( "#^HTTP/([0-9.]+) (.*)#", $header, $match ) ) {
+                               $this->respVersion = $match[1];
+                               $this->respStatus = $match[2];
+                       } elseif( preg_match( "#^[ \t]#", $header ) ) {
+                               $last = count($this->respHeaders[$lastname]) - 1;
+                               $this->respHeaders[$lastname][$last] .= "\r\n$header";
+                       } elseif( preg_match( "#^([^:]*):[\t ]*(.*)#", $header, $match ) ) {
+                               $this->respHeaders[strtolower( $match[1] )][] = $match[2];
+                               $lastname = strtolower( $match[1] );
+                       }
                }
 
-               session_write_close();
+               $this->parseCookies();
        }
 
        /**
-        * Take care of the downloaded file
-        * @param $sd array
-        * @param $status Status
+        * Sets the member variable status to a fatal status if the HTTP
+        * status code was not 200.
         *
-        * @returns Status
+        * @return nothing
         */
-       private static function doFauxRequest( $sd, $status ) {
-               global $wgEnableWriteAPI;
-
-               if ( $status->isOK() ) {
-                       $fauxReqData = $sd['mParams'];
-
-                       // Fix boolean parameters
-                       foreach ( $fauxReqData as $k => $v ) {
-                               if ( $v === false )
-                                       unset( $fauxReqData[$k] );
-                       }
+       protected function setStatus() {
+               if( !$this->respHeaders ) {
+                       $this->parseHeader();
+               }
 
-                       $fauxReqData['action'] = 'upload';
-                       $fauxReqData['format'] = 'json';
-                       $fauxReqData['internalhttpsession'] = $requestKey;
+               if((int)$this->respStatus !== 200) {
+                       list( $code, $message ) = explode(" ", $this->respStatus, 2);
+                       $this->status->fatal("http-bad-status", $code, $message );
+               }
+       }
 
-                       // evil but no other clean way about it:
-                       $fauxReq = new FauxRequest( $fauxReqData, true );
-                       $processor = new ApiMain( $fauxReq, $wgEnableWriteAPI );
 
-                       // init the mUpload var for the $processor
-                       $processor->execute();
-                       $processor->getResult()->cleanUpUTF8();
-                       $printer = $processor->createPrinterByName( 'json' );
-                       $printer->initPrinter( false );
-                       ob_start();
-                       $printer->execute();
+       /**
+        * Returns true if the last status code was a redirect.
+        *
+        * @return Boolean
+        */
+       public function isRedirect() {
+               if( !$this->respHeaders ) {
+                       $this->parseHeader();
+               }
 
-                       // the status updates runner will grab the result form the session:
-                       $status->value = ob_get_clean();
+               $status = (int)$this->respStatus;
+               if ( $status >= 300 && $status <= 303 ) {
+                       return true;
                }
-               return $status;
+               return false;
        }
 
        /**
-        * Run a session based download.
+        * Returns an associative array of response headers after the
+        * request has been executed.  Because some headers
+        * (e.g. Set-Cookie) can appear more than once the, each value of
+        * the associative array is an array of the values given.
         *
-        * @param $sessionID string: the session id with the download details
-        * @param $requestKey string: the key of the given upload session
-        *      (a given client could have started a few http uploads at once)
-        */
-       public static function doSessionIdDownload( $sessionID, $requestKey ) {
-               global $wgAsyncHTTPTimeout;
-
-               wfDebug( __METHOD__ . "\n\n doSessionIdDownload :\n\n" );
-               $sd = self::recoverSession( $sessionID );
-               $req = HttpRequest::factory( $sd['url'],
-                                                                        array(
-                                                                                'targetFilePath'         => $sd['targetFilePath'],
-                                                                                'requestKey'             => $requestKey,
-                                                                                'timeout'                        => $wgAsyncHTTPTimeout,
-                                                                        ) );
-
-               // run the actual request .. (this can take some time)
-               wfDebug( __METHOD__ . 'do Session Download :: ' . $sd['url'] . ' tf: ' .
-                                $sd['targetFilePath'] . "\n\n" );
-               $status = $req->doRequest();
-
-               self::updateSession( $sessionID, $requestKey,
-                                                        self::handleFauxResponse( $sd, $status ) );
+        * @return Array
+        */
+       public function getResponseHeaders() {
+               if( !$this->respHeaders ) {
+                       $this->parseHeader();
+               }
+               return $this->respHeaders;
        }
-}
-
-/**
- * This wrapper class will call out to curl (if available) or fallback
- * to regular PHP if necessary for handling internal HTTP requests.
- */
-class HttpRequest {
-       private $targetFilePath;
-       private $requestKey;
-       protected $content;
-       protected $timeout = 'default';
-       protected $headersOnly = null;
-       protected $postdata = null;
-       protected $proxy = null;
-       protected $no_proxy = false;
-       protected $sslVerifyHost = true;
-       protected $caInfo = null;
-       protected $method = "GET";
-       protected $url;
-       public $status;
 
        /**
-        * @param $url   string url to use
-        * @param $options array (optional) extra params to pass
-        *                               Possible keys for the array:
-        *                                      method
-        *                                      timeout
-        *                                      targetFilePath
-        *                                      requestKey
-        *                                      headersOnly
-        *                                      postdata
-        *                                      proxy
-        *                                      no_proxy
-        *                                      sslVerifyHost
-        *                                      caInfo
-        */
-       function __construct( $url = null, $opt ) {
-               global $wgHTTPTimeout;
+        * Returns the value of the given response header.
+        *
+        * @param $header String
+        * @return String
+        */
+       public function getResponseHeader($header) {
+               if( !$this->respHeaders ) {
+                       $this->parseHeader();
+               }
+               if ( isset( $this->respHeaders[strtolower ( $header ) ] ) ) {
+                       $v = $this->respHeaders[strtolower ( $header ) ];
+                       return $v[count( $v ) - 1];
+               }
+               return null;
+       }
 
-               $this->url = $url;
+       /**
+        * Tells the HttpRequest object to use this pre-loaded CookieJar.
+        *
+        * @param $jar CookieJar
+        */
+       public function setCookieJar( $jar ) {
+               $this->cookieJar = $jar;
+       }
 
-               if ( !ini_get( 'allow_url_fopen' ) ) {
-                       $this->status = Status::newFatal( 'allow_url_fopen needs to be enabled for http copy to work' );
-               } elseif ( !Http::isValidURI( $this->url ) ) {
-                       $this->status = Status::newFatal( 'bad-url' );
-               } else {
-                       $this->status = Status::newGood( 100 ); // continue
+       /**
+        * Returns the cookie jar in use.
+        *
+        * @returns CookieJar
+        */
+       public function getCookieJar() {
+               if( !$this->respHeaders ) {
+                       $this->parseHeader();
                }
+               return $this->cookieJar;
+       }
 
-               if ( array_key_exists( 'timeout', $opt ) && $opt['timeout'] != 'default' ) {
-                       $this->timeout = $opt['timeout'];
-               } else {
-                       $this->timeout = $wgHTTPTimeout;
+       /**
+        * Sets a cookie.  Used before a request to set up any individual
+        * cookies.      Used internally after a request to parse the
+        * Set-Cookie headers.
+        * @see Cookie::set
+        */
+       public function setCookie( $name, $value = null, $attr = null) {
+               if( !$this->cookieJar ) {
+                       $this->cookieJar = new CookieJar;
                }
+               $this->cookieJar->setCookie($name, $value, $attr);
+       }
 
-               $members = array( "targetFilePath", "requestKey", "headersOnly", "postdata",
-                                                "proxy", "no_proxy", "sslVerifyHost", "caInfo", "method" );
-               foreach ( $members as $o ) {
-                       if ( array_key_exists( $o, $opt ) ) {
-                               $this->$o = $opt[$o];
+       /**
+        * Parse the cookies in the response headers and store them in the cookie jar.
+        */
+       protected function parseCookies() {
+               if( !$this->cookieJar ) {
+                       $this->cookieJar = new CookieJar;
+               }
+               if( isset( $this->respHeaders['set-cookie'] ) ) {
+                       $url = parse_url( $this->getFinalUrl() );
+                       foreach( $this->respHeaders['set-cookie'] as $cookie ) {
+                               $this->cookieJar->parseCookieResponseHeader( $cookie, $url['host'] );
                        }
                }
+       }
 
-               if ( is_array( $this->postdata ) ) {
-                       $this->postdata = wfArrayToCGI( $this->postdata );
+       /**
+        * Returns the final URL after all redirections.
+        *
+        * @return String
+        */
+       public function getFinalUrl() {
+               $location = $this->getResponseHeader("Location");
+               if ( $location ) {
+                       return $location;
                }
+
+               return $this->url;
        }
 
        /**
-        * For backwards compatibility, we provide a __toString method so
-        * that any code that expects a string result from Http::Get()
-        * will see the content of the request.
+        * Returns true if the backend can follow redirects. Overridden by the 
+        * child classes.
         */
-       function __toString() {
-               return $this->content;
+       public function canFollowRedirects() {
+               return true;
+       }
+}
+
+
+class Cookie {
+       protected $name;
+       protected $value;
+       protected $expires;
+       protected $path;
+       protected $domain;
+       protected $isSessionKey = true;
+       // TO IMPLEMENT  protected $secure
+       // TO IMPLEMENT? protected $maxAge (add onto expires)
+       // TO IMPLEMENT? protected $version
+       // TO IMPLEMENT? protected $comment
+
+       function __construct( $name, $value, $attr ) {
+               $this->name = $name;
+               $this->set( $value, $attr );
        }
 
        /**
-        * Generate a new request object
-        * @see HttpRequest::__construct
+        * Sets a cookie.  Used before a request to set up any individual
+        * cookies.      Used internally after a request to parse the
+        * Set-Cookie headers.
+        *
+        * @param $value String: the value of the cookie
+        * @param $attr Array: possible key/values:
+        *              expires  A date string
+        *              path     The path this cookie is used on
+        *              domain   Domain this cookie is used on
         */
-       public static function factory( $url, $opt ) {
-               global $wgForceHTTPEngine;
-
-               if ( function_exists( 'curl_init' ) && $wgForceHTTPEngine == "curl" ) {
-                       return new CurlHttpRequest( $url, $opt );
+       public function set( $value, $attr ) {
+               $this->value = $value;
+               if( isset( $attr['expires'] ) ) {
+                       $this->isSessionKey = false;
+                       $this->expires = strtotime( $attr['expires'] );
+               }
+               if( isset( $attr['path'] ) ) {
+                       $this->path = $attr['path'];
+               } else {
+                       $this->path = "/";
+               }
+               if( isset( $attr['domain'] ) ) {
+                       if( self::validateCookieDomain( $attr['domain'] ) ) {
+                               $this->domain = $attr['domain'];
+                       }
                } else {
-                       return new PhpHttpRequest( $url, $opt );
+                       throw new MWException("You must specify a domain.");
                }
        }
 
-       public function getContent() {
-               return $this->content;
-       }
+       /**
+        * Return the true if the cookie is valid is valid.  Otherwise,
+        * false.  The uses a method similar to IE cookie security
+        * described here:
+        * http://kuza55.blogspot.com/2008/02/understanding-cookie-security.html
+        * A better method might be to use a blacklist like
+        * http://publicsuffix.org/
+        *
+        * @param $domain String: the domain to validate
+        * @param $originDomain String: (optional) the domain the cookie originates from
+        * @return Boolean
+        */
+       public static function validateCookieDomain( $domain, $originDomain = null) {
+               // Don't allow a trailing dot
+               if( substr( $domain, -1 ) == "." ) return false;
+
+               $dc = explode(".", $domain);
+
+               // Only allow full, valid IP addresses
+               if( preg_match( '/^[0-9.]+$/', $domain ) ) {
+                       if( count( $dc ) != 4 ) return false;
+
+                       if( ip2long( $domain ) === false ) return false;
+
+                       if( $originDomain == null || $originDomain == $domain ) return true;
 
-       public function handleOutput() {
-               // if we wrote to a target file close up or return error
-               if ( $this->targetFilePath ) {
-                       $this->writer->close();
-                       if ( !$this->writer->status->isOK() ) {
-                               $this->status = $this->writer->status;
-                               return $this->status;
+               }
+
+               // Don't allow cookies for "co.uk" or "gov.uk", etc, but allow "supermarket.uk"
+               if( strrpos( $domain, "." ) - strlen( $domain )  == -3 ) {
+                       if( (count($dc) == 2 && strlen( $dc[0] ) <= 2 )
+                               || (count($dc) == 3 && strlen( $dc[0] ) == "" && strlen( $dc[1] ) <= 2 ) ) {
+                               return false;
+                       }
+                       if( (count($dc) == 2 || (count($dc) == 3 && $dc[0] == "") )
+                               && preg_match( '/(com|net|org|gov|edu)\...$/', $domain) ) {
+                               return false;
                        }
                }
+
+               if( $originDomain != null ) {
+                       if( substr( $domain, 0, 1 ) != "." && $domain != $originDomain ) {
+                               return false;
+                       }
+                       if( substr( $domain, 0, 1 ) == "."
+                               && substr_compare( $originDomain, $domain, -strlen( $domain ),
+                                                                  strlen( $domain ), TRUE ) != 0 ) {
+                               return false;
+                       }
+               }
+
+               return true;
        }
 
-       public function doRequest() {
-               global $wgTitle;
+       /**
+        * Serialize the cookie jar into a format useful for HTTP Request headers.
+        *
+        * @param $path String: the path that will be used. Required.
+        * @param $domain String: the domain that will be used. Required.
+        * @return String
+        */
+       public function serializeToHttpRequest( $path, $domain ) {
+               $ret = "";
 
-               if ( !$this->status->isOK() ) {
-                       return $this->status;
+               if( $this->canServeDomain( $domain )
+                               && $this->canServePath( $path )
+                               && $this->isUnExpired() ) {
+                       $ret = $this->name ."=". $this->value;
                }
 
-               $this->initRequest();
+               return $ret;
+       }
 
-               if ( !$this->no_proxy ) {
-                       $this->proxySetup();
+       protected function canServeDomain( $domain ) {
+               if( $domain == $this->domain
+                       || ( strlen( $domain) > strlen( $this->domain )
+                                && substr( $this->domain, 0, 1) == "."
+                                && substr_compare( $domain, $this->domain, -strlen( $this->domain ),
+                                                                       strlen( $this->domain ), TRUE ) == 0 ) ) {
+                       return true;
                }
+               return false;
+       }
 
-               # Set the referer to $wgTitle, even in command-line mode
-               # This is useful for interwiki transclusion, where the foreign
-               # server wants to know what the referring page is.
-               # $_SERVER['REQUEST_URI'] gives a less reliable indication of the
-               # referring page.
-               if ( is_object( $wgTitle ) ) {
-                       $this->set_referer( $wgTitle->getFullURL() );
+       protected function canServePath( $path ) {
+               if( $this->path && substr_compare( $this->path, $path, 0, strlen( $this->path ) ) == 0 ) {
+                       return true;
                }
+               return false;
+       }
 
-               $this->setupOutputHandler();
-
-               if ( $this->status->isOK() ) {
-                       $this->spinTheWheel();
+       protected function isUnExpired() {
+               if( $this->isSessionKey || $this->expires > time() ) {
+                       return true;
                }
+               return false;
+       }
 
-               if ( !$this->status->isOK() ) {
-                       return $this->status;
+}
+
+class CookieJar {
+       private $cookie = array();
+
+       /**
+        * Set a cookie in the cookie jar.      Make sure only one cookie per-name exists.
+        * @see Cookie::set()
+        */
+       public function setCookie ($name, $value, $attr) {
+               /* cookies: case insensitive, so this should work.
+                * We'll still send the cookies back in the same case we got them, though.
+                */
+               $index = strtoupper($name);
+               if( isset( $this->cookie[$index] ) ) {
+                       $this->cookie[$index]->set( $value, $attr );
+               } else {
+                       $this->cookie[$index] = new Cookie( $name, $value, $attr );
                }
+       }
 
-               $this->handleOutput();
+       /**
+        * @see Cookie::serializeToHttpRequest
+        */
+       public function serializeToHttpRequest( $path, $domain ) {
+               $cookies = array();
 
-               $this->finish();
-               return $this->status;
+               foreach( $this->cookie as $c ) {
+                       $serialized = $c->serializeToHttpRequest( $path, $domain );
+                       if ( $serialized ) $cookies[] = $serialized;
+               }
+
+               return implode("; ", $cookies);
        }
 
-       public function setupOutputHandler() {
-               if ( $this->targetFilePath ) {
-                       $this->writer = new SimpleFileWriter( $this->targetFilePath,
-                                                                                                 $this->requestKey );
-                       if ( !$this->writer->status->isOK() ) {
-                               wfDebug( __METHOD__ . "ERROR in setting up SimpleFileWriter\n" );
-                               $this->status = $this->writer->status;
-                               return $this->status;
+       /**
+        * Parse the content of an Set-Cookie HTTP Response header.
+        *
+        * @param $cookie String
+        * @param $domain String: cookie's domain
+        */
+       public function parseCookieResponseHeader ( $cookie, $domain ) {
+               $len = strlen( "Set-Cookie:" );
+               if ( substr_compare( "Set-Cookie:", $cookie, 0, $len, TRUE ) === 0 ) {
+                       $cookie = substr( $cookie, $len );
+               }
+
+               $bit = array_map( 'trim', explode( ";", $cookie ) );
+               if ( count($bit) >= 1 ) {
+                       list($name, $value) = explode( "=", array_shift( $bit ), 2 );
+                       $attr = array();
+                       foreach( $bit as $piece ) {
+                               $parts = explode( "=", $piece );
+                               if( count( $parts ) > 1 ) {
+                                       $attr[strtolower( $parts[0] )] = $parts[1];
+                               } else {
+                                       $attr[strtolower( $parts[0] )] = true;
+                               }
                        }
-                       $this->setCallback( array( $this, 'readAndSave' ) );
-               } else {
-                       $this->setCallback( array( $this, 'readOnly' ) );
+
+                       if( !isset( $attr['domain'] ) ) {
+                               $attr['domain'] = $domain;
+                       } elseif ( !Cookie::validateCookieDomain( $attr['domain'], $domain ) ) {
+                               return null;
+                       }
+                       $this->setCookie( $name, $value, $attr );
                }
        }
 }
 
+
 /**
  * HttpRequest implemented using internal curl compiled into PHP
  */
 class CurlHttpRequest extends HttpRequest {
-       private $c;
-
-       public function initRequest() {
-               $this->c = curl_init( $this->url );
-       }
+       static $curlMessageMap = array(
+               6 => 'http-host-unreachable',
+               28 => 'http-timed-out'
+       );
 
-       public function proxySetup() {
-               global $wgHTTPProxy;
+       protected $curlOptions = array();
+       protected $headerText = "";
 
-               if ( is_string( $this->proxy ) ) {
-                       curl_setopt( $this->c, CURLOPT_PROXY, $this->proxy );
-               } else if ( Http::isLocalURL( $this->url ) ) { /* Not sure this makes any sense. */
-                       curl_setopt( $this->c, CURLOPT_PROXY, 'localhost:80' );
-               } else if ( $wgHTTPProxy ) {
-                       curl_setopt( $this->c, CURLOPT_PROXY, $wgHTTPProxy );
-               }
+       protected function readHeader( $fh, $content ) {
+               $this->headerText .= $content;
+               return strlen( $content );
        }
 
-       public function setCallback( $cb ) {
-               curl_setopt( $this->c, CURLOPT_WRITEFUNCTION, $cb );
-       }
+       public function execute() {
+               parent::execute();
+               if ( !$this->status->isOK() ) {
+                       return $this->status;
+               }
+               $this->curlOptions[CURLOPT_PROXY] = $this->proxy;
+               $this->curlOptions[CURLOPT_TIMEOUT] = $this->timeout;
+               $this->curlOptions[CURLOPT_HTTP_VERSION] = CURL_HTTP_VERSION_1_0;
+               $this->curlOptions[CURLOPT_WRITEFUNCTION] = $this->callback;
+               $this->curlOptions[CURLOPT_HEADERFUNCTION] = array($this, "readHeader");
+               $this->curlOptions[CURLOPT_MAXREDIRS] = $this->maxRedirects;
+               $this->curlOptions[CURLOPT_ENCODING] = ""; # Enable compression
 
-       public function spinTheWheel() {
-               curl_setopt( $this->c, CURLOPT_TIMEOUT, $this->timeout );
-               curl_setopt( $this->c, CURLOPT_USERAGENT, Http::userAgent() );
-               curl_setopt( $this->c, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_1_0 );
+               /* not sure these two are actually necessary */
+               if(isset($this->reqHeaders['Referer'])) {
+                       $this->curlOptions[CURLOPT_REFERER] = $this->reqHeaders['Referer'];
+               }
+               $this->curlOptions[CURLOPT_USERAGENT] = $this->reqHeaders['User-Agent'];
 
-               if ( $this->sslVerifyHost ) {
-                       curl_setopt( $this->c, CURLOPT_SSL_VERIFYHOST, $this->sslVerifyHost );
+               if ( isset( $this->sslVerifyHost ) ) {
+                       $this->curlOptions[CURLOPT_SSL_VERIFYHOST] = $this->sslVerifyHost;
+               }
+               
+               if ( isset( $this->sslVerifyCert ) ) {
+                       $this->curlOptions[CURLOPT_SSL_VERIFYPEER] = $this->sslVerifyCert;
                }
 
                if ( $this->caInfo ) {
-                       curl_setopt( $this->c, CURLOPT_CAINFO, $this->caInfo );
+                       $this->curlOptions[CURLOPT_CAINFO] = $this->caInfo;
                }
 
                if ( $this->headersOnly ) {
-                       curl_setopt( $this->c, CURLOPT_NOBODY, true );
-                       curl_setopt( $this->c, CURLOPT_HEADER, true );
+                       $this->curlOptions[CURLOPT_NOBODY] = true;
+                       $this->curlOptions[CURLOPT_HEADER] = true;
                } elseif ( $this->method == 'POST' ) {
-                       curl_setopt( $this->c, CURLOPT_POST, true );
-                       curl_setopt( $this->c, CURLOPT_POSTFIELDS, $this->postdata );
+                       $this->curlOptions[CURLOPT_POST] = true;
+                       $this->curlOptions[CURLOPT_POSTFIELDS] = $this->postData;
                        // Suppress 'Expect: 100-continue' header, as some servers
                        // will reject it with a 417 and Curl won't auto retry
                        // with HTTP 1.0 fallback
-                       curl_setopt( $this->c, CURLOPT_HTTPHEADER, array( 'Expect:' ) );
+                       $this->reqHeaders['Expect'] = '';
                } else {
-                       curl_setopt( $this->c, CURLOPT_CUSTOMREQUEST, $this->method );
+                       $this->curlOptions[CURLOPT_CUSTOMREQUEST] = $this->method;
                }
 
-               try {
-                       if ( false === curl_exec( $this->c ) ) {
-                               $error_txt = 'Error sending request: #' . curl_errno( $this->c ) . ' ' . curl_error( $this->c );
-                               wfDebug( __METHOD__ . $error_txt . "\n" );
-                               $this->status->fatal( $error_txt ); /* i18n? */
-                       }
-               } catch ( Exception $e ) {
-                       $errno = curl_errno( $this->c );
-                       if ( $errno != CURLE_OK ) {
-                               $errstr = curl_error( $this->c );
-                               wfDebug( __METHOD__ . ": CURL error code $errno: $errstr\n" );
-                               $this->status->fatal( "CURL error code $errno: $errstr\n" ); /* i18n? */
+               $this->curlOptions[CURLOPT_HTTPHEADER] = $this->getHeaderList();
+
+               $curlHandle = curl_init( $this->url );
+               if ( !curl_setopt_array( $curlHandle, $this->curlOptions ) ) {
+                       throw new MWException("Error setting curl options.");
+               }
+               if ( $this->followRedirects && $this->canFollowRedirects() ) {
+                       if ( ! @curl_setopt( $curlHandle, CURLOPT_FOLLOWLOCATION, true ) ) {
+                               wfDebug( __METHOD__.": Couldn't set CURLOPT_FOLLOWLOCATION. " .
+                                       "Probably safe_mode or open_basedir is set.\n");
+                               // Continue the processing. If it were in curl_setopt_array, 
+                               // processing would have halted on its entry
                        }
                }
-       }
 
-       public function readOnly( $curlH, $content ) {
-               $this->content .= $content;
-               return strlen( $content );
-       }
+               if ( false === curl_exec( $curlHandle ) ) {
+                       $code = curl_error( $curlHandle );
 
-       public function readAndSave( $curlH, $content ) {
-               return $this->writer->write( $content );
-       }
-
-       public function getCode() {
-               # Don't return truncated output
-               $code = curl_getinfo( $this->c, CURLINFO_HTTP_CODE );
-               if ( $code < 400 ) {
-                       $this->status->setResult( true, $code );
+                       if ( isset( self::$curlMessageMap[$code] ) ) {
+                               $this->status->fatal( self::$curlMessageMap[$code] );
+                       } else {
+                               $this->status->fatal( 'http-curl-error', curl_error( $curlHandle ) );
+                       }
                } else {
-                       $this->status->setResult( false, $code );
+                       $this->headerList = explode("\r\n", $this->headerText);
                }
-       }
 
-       public function finish() {
-               curl_close( $this->c );
-       }
-
-}
+               curl_close( $curlHandle );
 
-class PhpHttpRequest extends HttpRequest {
-       private $reqHeaders;
-       private $callback;
-       private $fh;
-
-       public function initRequest() {
-               $this->reqHeaders[] = "User-Agent: " . Http::userAgent();
-               $this->reqHeaders[] = "Accept: */*";
-               if ( $this->method == 'POST' ) {
-                       // Required for HTTP 1.0 POSTs
-                       $this->reqHeaders[] = "Content-Length: " . strlen( $this->postdata );
-                       $this->reqHeaders[] = "Content-type: application/x-www-form-urlencoded";
-               }
+               $this->parseHeader();
+               $this->setStatus();
+               return $this->status;
        }
 
-       public function proxySetup() {
-               global $wgHTTPProxy;
-
-               if ( $this->proxy ) {
-                       $this->proxy = 'tcp://' . $this->proxy;
-               } elseif ( Http::isLocalURL( $this->url ) ) {
-                       $this->proxy = 'tcp://localhost:80';
-               } elseif ( $wgHTTPProxy ) {
-                       $this->proxy = 'tcp://' . $wgHTTPProxy ;
+       public function canFollowRedirects() {
+               if ( strval( ini_get( 'open_basedir' ) ) !== '' || wfIniGetBool( 'safe_mode' ) ) {
+                       wfDebug( "Cannot follow redirects in safe mode\n" );
+                       return false;
                }
+               if ( !defined( 'CURLOPT_REDIR_PROTOCOLS' ) ) {
+                       wfDebug( "Cannot follow redirects with libcurl < 7.19.4 due to CVE-2009-0037\n" );
+                       return false;
+               }
+               return true;
        }
+}
 
-       public function setReferrer( $url ) {
-               $this->reqHeaders[] = "Referer: $url";
-       }
+class PhpHttpRequest extends HttpRequest {
+       protected function urlToTcp( $url ) {
+               $parsedUrl = parse_url( $url );
 
-       public function setCallback( $cb ) {
-               $this->callback = $cb;
+               return 'tcp://' . $parsedUrl['host'] . ':' . $parsedUrl['port'];
        }
 
-       public function readOnly( $contents ) {
-               if ( $this->headersOnly ) {
-                       return false;
-               }
-               $this->content .= $contents;
+       public function execute() {
+               parent::execute();
 
-        return strlen( $contents );
-       }
+               // At least on Centos 4.8 with PHP 5.1.6, using max_redirects to follow redirects
+               // causes a segfault
+               $manuallyRedirect = version_compare( phpversion(), '5.1.7', '<' );
 
-       public function readAndSave( $contents ) {
-               if ( $this->headersOnly ) {
-                       return false;
+               if ( $this->parsedUrl['scheme'] != 'http' ) {
+                       $this->status->fatal( 'http-invalid-scheme', $this->parsedUrl['scheme'] );
                }
-               return $this->writer->write( $content );
-       }
 
-       public function finish() {
-               fclose( $this->fh );
-       }
+               $this->reqHeaders['Accept'] = "*/*";
+               if ( $this->method == 'POST' ) {
+                       // Required for HTTP 1.0 POSTs
+                       $this->reqHeaders['Content-Length'] = strlen( $this->postData );
+                       $this->reqHeaders['Content-type'] = "application/x-www-form-urlencoded";
+               }
 
-       public function spinTheWheel() {
-               $opts = array();
-               if ( $this->proxy && !$this->no_proxy ) {
-                       $opts['proxy'] = $this->proxy;
-                       $opts['request_fulluri'] = true;
+               $options = array();
+               if ( $this->proxy && !$this->noProxy ) {
+                       $options['proxy'] = $this->urlToTCP( $this->proxy );
+                       $options['request_fulluri'] = true;
                }
 
-               $opts['method'] = $this->method;
-               $opts['timeout'] = $this->timeout;
-               $opts['header'] = implode( "\r\n", $this->reqHeaders );
-               if ( version_compare( "5.3.0", phpversion(), ">" ) ) {
-                       $opts['protocol_version'] = "1.0";
+               if ( !$this->followRedirects || $manuallyRedirect ) {
+                       $options['max_redirects'] = 0;
                } else {
-                       $opts['protocol_version'] = "1.1";
+                       $options['max_redirects'] = $this->maxRedirects;
                }
 
-               if ( $this->postdata ) {
-                       $opts['content'] = $this->postdata;
-               }
+               $options['method'] = $this->method;
+               $options['header'] = implode("\r\n", $this->getHeaderList());
+               // Note that at some future point we may want to support
+               // HTTP/1.1, but we'd have to write support for chunking
+               // in version of PHP < 5.3.1
+               $options['protocol_version'] = "1.0";
 
-               $context = stream_context_create( array( 'http' => $opts ) );
-               $this->fh = fopen( $this->url, "r", false, $context );
-               $result = stream_get_meta_data( $this->fh );
+               // This is how we tell PHP we want to deal with 404s (for example) ourselves.
+               // Only works on 5.2.10+
+               $options['ignore_errors'] = true;
 
-               if ( $result['timed_out'] ) {
-                       $this->status->error( __CLASS__ . '::timed-out-in-headers' );
+               if ( $this->postData ) {
+                       $options['content'] = $this->postData;
                }
 
-               $this->headers = $result['wrapper_data'];
-
-               $end = false;
-               $size = 8192;
-               while ( !$end ) {
-                       $contents = fread( $this->fh, $size );
-                       $size = call_user_func( $this->callback, $contents );
-                       $end = ( $size == 0 )  || feof( $this->fh );
+               $oldTimeout = false;
+               if ( version_compare( '5.2.1', phpversion(), '>' ) ) {
+                       $oldTimeout = ini_set('default_socket_timeout', $this->timeout);
+               } else {
+                       $options['timeout'] = $this->timeout;
                }
-       }
-}
 
-/**
- * SimpleFileWriter with session id updates
- */
-class SimpleFileWriter {
-       private $targetFilePath = null;
-       private $status = null;
-       private $sessionId = null;
-       private $sessionUpdateInterval = 0; // how often to update the session while downloading
-       private $currentFileSize = 0;
-       private $requestKey = null;
-       private $prevTime = 0;
-       private $fp = null;
+               $context = stream_context_create( array( 'http' => $options ) );
 
-       /**
-        * @param $targetFilePath string the path to write the file out to
-        * @param $requestKey string the request to update
-        */
-       function __construct__( $targetFilePath, $requestKey ) {
-               $this->targetFilePath = $targetFilePath;
-               $this->requestKey = $requestKey;
-               $this->status = Status::newGood();
-               // open the file:
-               $this->fp = fopen( $this->targetFilePath, 'w' );
-               if ( $this->fp === false ) {
-                       $this->status = Status::newFatal( 'HTTP::could-not-open-file-for-writing' );
-               }
-               // true start time
-               $this->prevTime = time();
-       }
+               $this->headerList = array();
+               $reqCount = 0;
+               $url = $this->url;
+               do {
+                       $reqCount++;
+                       wfSuppressWarnings();
+                       $fh = fopen( $url, "r", false, $context );
+                       wfRestoreWarnings();
+                       if ( !$fh ) {
+                               break;
+                       }
+                       $result = stream_get_meta_data( $fh );
+                       $this->headerList = $result['wrapper_data'];
+                       $this->parseHeader();
+                       if ( !$manuallyRedirect || !$this->followRedirects ) {
+                               break;
+                       }
 
-       public function write( $dataPacket ) {
-               global $wgMaxUploadSize, $wgLang;
+                       # Handle manual redirection
+                       if ( !$this->isRedirect() || $reqCount > $this->maxRedirects ) {
+                               break;
+                       }
+                       # Check security of URL
+                       $url = $this->getResponseHeader("Location");
+                       if ( substr( $url, 0, 7 ) !== 'http://' ) {
+                               wfDebug( __METHOD__.": insecure redirection\n" );
+                               break;
+                       }
+               } while ( true );
 
-               if ( !$this->status->isOK() ) {
-                       return false;
+               if ( $oldTimeout !== false ) {
+                       ini_set('default_socket_timeout', $oldTimeout);
                }
+               $this->setStatus();
 
-               // write out the content
-               if ( fwrite( $this->fp, $dataPacket ) === false ) {
-                       wfDebug( __METHOD__ . " ::could-not-write-to-file\n" );
-                       $this->status = Status::newFatal( 'HTTP::could-not-write-to-file' );
-                       return false;
+               if ( $fh === false ) {
+                       $this->status->fatal( 'http-request-error' );
+                       return $this->status;
                }
 
-               // check file size:
-               clearstatcache();
-               $this->currentFileSize = filesize( $this->targetFilePath );
-
-               if ( $this->currentFileSize > $wgMaxUploadSize ) {
-                       wfDebug( __METHOD__ . " ::http-download-too-large\n" );
-                       $this->status = Status::newFatal( 'HTTP::file-has-grown-beyond-upload-limit-killing: ' . /* i18n? */
-                                                                                         'downloaded more than ' .
-                                                                                         $wgLang->formatSize( $wgMaxUploadSize ) . ' ' );
-                       return false;
-               }
-               // if more than session_update_interval second have passed updateProgress
-               if ( $this->requestKey &&
-                       ( ( time() - $this->prevTime ) > $this->sessionUpdateInterval ) ) {
-                       $this->prevTime = time();
-                       $session_status = $this->updateProgress();
-                       if ( !$session_status->isOK() ) {
-                               $this->status = $session_status;
-                               wfDebug( __METHOD__ . ' update session failed or was canceled' );
-                               return false;
-                       }
+               if ( $result['timed_out'] ) {
+                       $this->status->fatal( 'http-timed-out', $this->url );
+                       return $this->status;
                }
-               return strlen( $dataPacket );
-       }
-
-       public function updateProgress() {
-               global $wgSessionsInMemcached;
 
-               // start the session (if necessary)
-               if ( !$wgSessionsInMemcached ) {
-                       wfSuppressWarnings();
-                       if ( session_start() === false ) {
-                               wfDebug( __METHOD__ . ' could not start session' );
-                               exit( 0 );
+               if($this->status->isOK()) {
+                       while ( !feof( $fh ) ) {
+                               $buf = fread( $fh, 8192 );
+                               if ( $buf === false ) {
+                                       $this->status->fatal( 'http-read-error' );
+                                       break;
+                               }
+                               if ( strlen( $buf ) ) {
+                                       call_user_func( $this->callback, $fh, $buf );
+                               }
                        }
-                       wfRestoreWarnings();
-               }
-               $sd =& $_SESSION['wsBgRequest'][ $this->requestKey ];
-               // check if the user canceled the request:
-               if ( $sd['userCancel'] ) {
-                       // @@todo kill the download
-                       return Status::newFatal( 'user-canceled-request' );
                }
-               // update the progress bytes download so far:
-               $sd['loaded'] = $this->currentFileSize;
-
-               // close down the session so we can other http queries can get session updates:
-               if ( !$wgSessionsInMemcached )
-                       session_write_close();
-
-               return Status::newGood();
-       }
-
-       public function close() {
-               $this->updateProgress();
+               fclose( $fh );
 
-               // close up the file handle:
-               if ( false === fclose( $this->fp ) ) {
-                       $this->status = Status::newFatal( 'HTTP::could-not-close-file' );
-               }
+               return $this->status;
        }
-
 }