includes/HttpFunctions.php

   1 <?php
   2 /**
   3  * HTTP handling class
   4  * @defgroup HTTP HTTP
   5  * @file
   6  * @ingroup HTTP
   7  */
   8
   9 class Http {
  10         const SYNC_DOWNLOAD = 1;  // syncronys upload (in a single request)
  11         const ASYNC_DOWNLOAD = 2; // asynchronous upload we should spawn out another process and monitor progress if possible)
  12
  13         var $body = '';
  14
  15         public static function request( $method, $url, $opts = array() ){
  16                 $opts['method'] = ( strtoupper( $method ) == 'GET' || strtoupper( $method ) == 'POST' ) ? strtoupper( $method ) : null;
  17                 $req = new HttpRequest( $url, $opts );
  18                 $status = $req->doRequest();
  19                 if( $status->isOK() ){
  20                         return $status->value;
  21                 } else {
  22                         wfDebug( 'http error: ' . $status->getWikiText() );
  23                         return false;
  24                 }
  25         }
  26
  27         /**
  28          * Simple wrapper for Http::request( 'GET' )
  29          */
  30         public static function get( $url, $timeout = false, $opts = array() ) {
  31                 global $wgSyncHTTPTimeout;
  32                 if( $timeout )
  33                         $opts['timeout'] = $timeout;
  34                 return Http::request( 'GET', $url, $opts );
  35         }
  36
  37         /**
  38          * Simple wrapper for Http::request( 'POST' )
  39          */
  40         public static function post( $url, $opts = array() ) {
  41                 return Http::request( 'POST', $url, $opts );
  42         }
  43
  44         public static function doDownload( $url, $target_file_path, $dl_mode = self::SYNC_DOWNLOAD, $redirectCount = 0 ){
  45                 global $wgPhpCli, $wgMaxUploadSize, $wgMaxRedirects;
  46                 // do a quick check to HEAD to insure the file size is not > $wgMaxUploadSize
  47                 $headRequest = new HttpRequest( $url, array( 'headers_only' => true ) );
  48                 $headResponse = $headRequest->doRequest();
  49                 if( !$headResponse->isOK() ){
  50                         return $headResponse;
  51                 }
  52                 $head = $headResponse->value;
  53
  54                 // check for redirects:
  55                 if( isset( $head['Location'] ) && strrpos( $head[0], '302' ) !== false ){
  56                         if( $redirectCount < $wgMaxRedirects ){
  57                                 if( self::isValidURI( $head['Location'] ) ){
  58                                         return self::doDownload( $head['Location'], $target_file_path, $dl_mode, $redirectCount++ );
  59                                 } else {
  60                                         return Status::newFatal( 'upload-proto-error' );
  61                                 }
  62                         } else {
  63                                 return Status::newFatal( 'upload-too-many-redirects' );
  64                         }
  65                 }
  66                 // we did not get a 200 ok response:
  67                 if( strrpos( $head[0], '200 OK' ) === false ){
  68                         return Status::newFatal( 'upload-http-error', htmlspecialchars( $head[0] ) );
  69                 }
  70
  71                 $content_length = ( isset( $head['Content-Length'] ) ) ? $head['Content-Length'] : null;
  72                 if( $content_length ){
  73                         if( $content_length > $wgMaxUploadSize ){
  74                                 return Status::newFatal( 'requested file length ' . $content_length . ' is greater than $wgMaxUploadSize: ' . $wgMaxUploadSize );
  75                         }
  76                 }
  77
  78                 // check if we can find phpCliPath (for doing a background shell request to php to do the download:
  79                 if( $wgPhpCli && wfShellExecEnabled() && $dl_mode == self::ASYNC_DOWNLOAD ){
  80                         wfDebug( __METHOD__ . "\ASYNC_DOWNLOAD\n" );
  81                         //setup session and shell call:
  82                         return self::initBackgroundDownload( $url, $target_file_path, $content_length );
  83                 } else {
  84                         wfDebug( __METHOD__ . "\nSYNC_DOWNLOAD\n" );
  85                         // SYNC_DOWNLOAD download as much as we can in the time we have to execute
  86                         $opts['method'] = 'GET';
  87                         $opts['target_file_path'] = $target_file_path;
  88                         $req = new HttpRequest( $url, $opts );
  89                         return $req->doRequest();
  90                 }
  91         }
  92
  93         /**
  94          * a non blocking request (generally an exit point in the application)
  95          * should write to a file location and give updates
  96          *
  97          */
  98         private static function initBackgroundDownload( $url, $target_file_path, $content_length = null ){
  99                 global $wgMaxUploadSize, $IP, $wgPhpCli, $wgServer;
 100                 $status = Status::newGood();
 101
 102                 // generate a session id with all the details for the download (pid, target_file_path )
 103                 $upload_session_key = self::getUploadSessionKey();
 104                 $session_id = session_id();
 105
 106                 // store the url and target path:
 107                 $_SESSION['wsDownload'][$upload_session_key]['url'] = $url;
 108                 $_SESSION['wsDownload'][$upload_session_key]['target_file_path'] = $target_file_path;
 109                 // since we request from the cmd line we lose the original host name pass in the session:
 110                 $_SESSION['wsDownload'][$upload_session_key]['orgServer'] = $wgServer;
 111
 112                 if( $content_length )
 113                         $_SESSION['wsDownload'][$upload_session_key]['content_length'] = $content_length;
 114
 115                 // set initial loaded bytes:
 116                 $_SESSION['wsDownload'][$upload_session_key]['loaded'] = 0;
 117
 118                 // run the background download request:
 119                 $cmd = $wgPhpCli . ' ' . $IP . "/maintenance/http_session_download.php --sid {$session_id} --usk {$upload_session_key}";
 120                 $pid = wfShellBackgroundExec( $cmd );
 121                 // the pid is not of much use since we won't be visiting this same apache any-time soon.
 122                 if( !$pid )
 123                         return Status::newFatal( 'could not run background shell exec' );
 124
 125                 // update the status value with the $upload_session_key (for the user to check on the status of the upload)
 126                 $status->value = $upload_session_key;
 127
 128                 // return good status
 129                 return $status;
 130         }
 131
 132         static function getUploadSessionKey(){
 133                 $key = mt_rand( 0, 0x7fffffff );
 134                 $_SESSION['wsUploadData'][$key] = array();
 135                 return $key;
 136         }
 137
 138         /**
 139          * used to run a session based download. Is initiated via the shell.
 140          *
 141          * @param $session_id String: the session id to grab download details from
 142          * @param $upload_session_key String: the key of the given upload session
 143          *  (a given client could have started a few http uploads at once)
 144          */
 145         public static function doSessionIdDownload( $session_id, $upload_session_key ){
 146                 global $wgUser, $wgEnableWriteAPI, $wgAsyncHTTPTimeout, $wgServer,
 147                                 $wgSessionsInMemcached, $wgSessionHandler, $wgSessionStarted;
 148                 wfDebug( __METHOD__ . "\n\n doSessionIdDownload :\n\n" );
 149                 // set session to the provided key:
 150                 session_id( $session_id );
 151                 //fire up mediaWiki session system:
 152                 wfSetupSession();
 153
 154                 // start the session
 155                 if( session_start() === false ){
 156                         wfDebug( __METHOD__ . ' could not start session' );
 157                 }
 158                 // get all the vars we need from session_id
 159                 if( !isset( $_SESSION[ 'wsDownload' ][$upload_session_key] ) ){
 160                         wfDebug(  __METHOD__ . ' Error:could not find upload session');
 161                         exit();
 162                 }
 163                 // setup the global user from the session key we just inherited
 164                 $wgUser = User::newFromSession();
 165
 166                 // grab the session data to setup the request:
 167                 $sd =& $_SESSION['wsDownload'][$upload_session_key];
 168
 169                 // update the wgServer var ( since cmd line thinks we are localhost when we are really orgServer)
 170                 if( isset( $sd['orgServer'] ) && $sd['orgServer'] ){
 171                         $wgServer = $sd['orgServer'];
 172                 }
 173                 // close down the session so we can other http queries can get session updates: (if not $wgSessionsInMemcached)
 174                 if( !$wgSessionsInMemcached )
 175                         session_write_close();
 176
 177                 $req = new HttpRequest( $sd['url'], array(
 178                         'target_file_path'  => $sd['target_file_path'],
 179                         'upload_session_key'=> $upload_session_key,
 180                         'timeout'           => $wgAsyncHTTPTimeout,
 181                         'do_close_session_update' => true
 182                 ) );
 183                 // run the actual request .. (this can take some time)
 184                 wfDebug( __METHOD__ . 'do Session Download :: ' . $sd['url'] . ' tf: ' . $sd['target_file_path'] . "\n\n");
 185                 $status = $req->doRequest();
 186                 //wfDebug("done with req status is: ". $status->isOK(). ' '.$status->getWikiText(). "\n");
 187
 188                 // start up the session again:
 189                 if( session_start() === false ){
 190                         wfDebug( __METHOD__ . ' ERROR:: Could not start session');
 191                 }
 192                 // grab the updated session data pointer
 193                 $sd =& $_SESSION['wsDownload'][$upload_session_key];
 194                 // if error update status:
 195                 if( !$status->isOK() ){
 196                         $sd['apiUploadResult'] = ApiFormatJson::getJsonEncode(
 197                                 array( 'error' => $status->getWikiText() )
 198                         );
 199                 }
 200                 // if status okay process upload using fauxReq to api:
 201                 if( $status->isOK() ){
 202                         // setup the FauxRequest
 203                         $fauxReqData = $sd['mParams'];
 204
 205                         // Fix boolean parameters
 206                         foreach( $fauxReqData as $k => $v ) {
 207                                 if( $v === false )
 208                                         unset( $fauxReqData[$k] );
 209                         }
 210
 211                         $fauxReqData['action'] = 'upload';
 212                         $fauxReqData['format'] = 'json';
 213                         $fauxReqData['internalhttpsession'] = $upload_session_key;
 214                         // evil but no other clean way about it:
 215                         $faxReq = new FauxRequest( $fauxReqData, true );
 216                         $processor = new ApiMain( $faxReq, $wgEnableWriteAPI );
 217
 218                         //init the mUpload var for the $processor
 219                         $processor->execute();
 220                         $processor->getResult()->cleanUpUTF8();
 221                         $printer = $processor->createPrinterByName( 'json' );
 222                         $printer->initPrinter( false );
 223                         ob_start();
 224                         $printer->execute();
 225                         $apiUploadResult = ob_get_clean();
 226
 227                         // the status updates runner will grab the result form the session:
 228                         $sd['apiUploadResult'] = $apiUploadResult;
 229                 }
 230                 // close the session:
 231                 session_write_close();
 232         }
 233
 234         /**
 235          * Check if the URL can be served by localhost
 236          * @param $url string Full url to check
 237          * @return bool
 238          */
 239         public static function isLocalURL( $url ) {
 240                 global $wgCommandLineMode, $wgConf;
 241                 if ( $wgCommandLineMode ) {
 242                         return false;
 243                 }
 244
 245                 // Extract host part
 246                 $matches = array();
 247                 if ( preg_match( '!^http://([\w.-]+)[/:].*$!', $url, $matches ) ) {
 248                         $host = $matches[1];
 249                         // Split up dotwise
 250                         $domainParts = explode( '.', $host );
 251                         // Check if this domain or any superdomain is listed in $wgConf as a local virtual host
 252                         $domainParts = array_reverse( $domainParts );
 253                         for ( $i = 0; $i < count( $domainParts ); $i++ ) {
 254                                 $domainPart = $domainParts[$i];
 255                                 if ( $i == 0 ) {
 256                                         $domain = $domainPart;
 257                                 } else {
 258                                         $domain = $domainPart . '.' . $domain;
 259                                 }
 260                                 if ( $wgConf->isLocalVHost( $domain ) ) {
 261                                         return true;
 262                                 }
 263                         }
 264                 }
 265                 return false;
 266         }
 267
 268         /**
 269          * Return a standard user-agent we can use for external requests.
 270          */
 271         public static function userAgent() {
 272                 global $wgVersion;
 273                 return "MediaWiki/$wgVersion";
 274         }
 275
 276         /**
 277          * Checks that the given URI is a valid one
 278          * @param $uri Mixed: URI to check for validity
 279          */
 280         public static function isValidURI( $uri ){
 281                 return preg_match(
 282                         '/(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/',
 283                         $uri,
 284                         $matches
 285                 );
 286         }
 287 }
 288
 289 class HttpRequest {
 290         var $target_file_path;
 291         var $upload_session_key;
 292         var $supportedCurlOpts = array(
 293                 'CURLOPT_SSL_VERIFYHOST',
 294                 'CURLOPT_CAINFO',
 295                 'CURLOPT_COOKIE',
 296                 'CURLOPT_FOLLOWLOCATION',
 297                 'CURLOPT_FAILONERROR'
 298         );
 299         function __construct( $url, $opt ){
 300                 global $wgSyncHTTPTimeout;
 301                 // double check that it's a valid url:
 302                 $this->url = $url;
 303
 304                 // set the timeout to default sync timeout (unless the timeout option is provided)
 305                 $this->timeout = ( isset( $opt['timeout'] ) ) ? $opt['timeout'] : $wgSyncHTTPTimeout;
 306                 //check special key default
 307                 if($this->timeout == 'default'){
 308                         $opts['timeout'] = $wgSyncHTTPTimeout;
 309                 }
 310
 311                 $this->method = ( isset( $opt['method'] ) ) ? $opt['method'] : 'GET';
 312                 $this->target_file_path = ( isset( $opt['target_file_path'] ) ) ? $opt['target_file_path'] : false;
 313                 $this->upload_session_key = ( isset( $opt['upload_session_key'] ) ) ? $opt['upload_session_key'] : false;
 314                 $this->headers_only = ( isset( $opt['headers_only'] ) ) ? $opt['headers_only'] : false;
 315                 $this->do_close_session_update = isset( $opt['do_close_session_update'] );
 316                 $this->postData = isset( $opt['postdata'] ) ? $opt['postdata'] : '';
 317
 318                 $this->curlOpt = array();
 319                 //check for some curl options:
 320                 foreach($this->supportedCurlOpts as $curlOpt){
 321                         if(isset($opt[ $curlOpt ])){
 322                                 $this->curlOpt[$curlOpt] = $opt[ $curlOpt ];
 323                         }
 324                 }
 325         }
 326
 327         /**
 328          * Get the contents of a file by HTTP
 329          * @param $url string Full URL to act on
 330          * @param $Opt associative array Optional array of options:
 331          *     'method'           => 'GET', 'POST' etc.
 332          *     'target_file_path' => if curl should output to a target file
 333          *     'adapter'          => 'curl', 'soket'
 334          */
 335         public function doRequest() {
 336                 # Make sure we have a valid url
 337                 if( !Http::isValidURI( $this->url ) )
 338                         return Status::newFatal('bad-url');
 339
 340                 # Use curl if available
 341                 if ( function_exists( 'curl_init' ) ) {
 342                         return $this->doCurlReq();
 343                 } else {
 344                         return $this->doPhpReq();
 345                 }
 346         }
 347
 348         private function doCurlReq(){
 349                 global $wgHTTPProxy, $wgTitle;
 350
 351                 $status = Status::newGood();
 352                 $c = curl_init( $this->url );
 353
 354                 // proxy setup:
 355                 if ( Http::isLocalURL( $this->url ) ) {
 356                         curl_setopt( $c, CURLOPT_PROXY, 'localhost:80' );
 357                 } else if ( $wgHTTPProxy ) {
 358                         curl_setopt( $c, CURLOPT_PROXY, $wgHTTPProxy );
 359                 }
 360
 361                 curl_setopt( $c, CURLOPT_TIMEOUT, $this->timeout );
 362                 curl_setopt( $c, CURLOPT_USERAGENT, Http::userAgent() );
 363
 364                 //set any curl specific opts:
 365                 foreach($this->curlOpt as $optKey => $optVal){
 366                         curl_setopt($c, constant( $optKey ),  $optVal);
 367                 }
 368
 369                 if ( $this->headers_only ) {
 370                         curl_setopt( $c, CURLOPT_NOBODY, true );
 371                         curl_setopt( $c, CURLOPT_HEADER, true );
 372                 } elseif ( $this->method == 'POST' ) {
 373                         curl_setopt( $c, CURLOPT_POST, true );
 374                         curl_setopt( $c, CURLOPT_POSTFIELDS, $this->postData );
 375                         // Suppress 'Expect: 100-continue' header, as some servers
 376                         // will reject it with a 417 and Curl won't auto retry
 377                         // with HTTP 1.0 fallback
 378                         curl_setopt( $c, CURLOPT_HTTPHEADER, array( 'Expect:' ) );
 379                 } else {
 380                         curl_setopt( $c, CURLOPT_CUSTOMREQUEST, $this->method );
 381                 }
 382
 383                 # Set the referer to $wgTitle, even in command-line mode
 384                 # This is useful for interwiki transclusion, where the foreign
 385                 # server wants to know what the referring page is.
 386                 # $_SERVER['REQUEST_URI'] gives a less reliable indication of the
 387                 # referring page.
 388                 if ( is_object( $wgTitle ) ) {
 389                         curl_setopt( $c, CURLOPT_REFERER, $wgTitle->getFullURL() );
 390                 }
 391
 392                 // set the write back function (if we are writing to a file)
 393                 if( $this->target_file_path ){
 394                         $cwrite = new simpleFileWriter( $this->target_file_path,
 395                                 $this->upload_session_key,
 396                                 $this->do_close_session_update
 397                         );
 398                         if( !$cwrite->status->isOK() ){
 399                                 wfDebug( __METHOD__ . "ERROR in setting up simpleFileWriter\n" );
 400                                 $status = $cwrite->status;
 401                                 return $status;
 402                         }
 403                         curl_setopt( $c, CURLOPT_WRITEFUNCTION, array( $cwrite, 'callbackWriteBody' ) );
 404                 }
 405
 406                 // start output grabber:
 407                 if( !$this->target_file_path )
 408                         ob_start();
 409
 410                 //run the actual curl_exec:
 411                 try {
 412                         if ( false === curl_exec( $c ) ) {
 413                                 $error_txt ='Error sending request: #' . curl_errno( $c ) .' '. curl_error( $c );
 414                                 wfDebug( __METHOD__ . $error_txt . "\n" );
 415                                 $status = Status::newFatal( $error_txt );
 416                         }
 417                 } catch ( Exception $e ) {
 418                         // do something with curl exec error?
 419                 }
 420                 // if direct request output the results to the stats value:
 421                 if( !$this->target_file_path && $status->isOK() ){
 422                         $status->value = ob_get_contents();
 423                         ob_end_clean();
 424                 }
 425                 // if we wrote to a target file close up or return error
 426                 if( $this->target_file_path ){
 427                         $cwrite->close();
 428                         if( !$cwrite->status->isOK() ){
 429                                 return $cwrite->status;
 430                         }
 431                 }
 432
 433                 if ( $this->headers_only ) {
 434                         $headers = explode( "\n", $status->value );
 435                         $headerArray = array();
 436                         foreach ( $headers as $header ) {
 437                                 if ( !strlen( trim( $header ) ) )
 438                                         continue;
 439                                 $headerParts = explode( ':', $header, 2 );
 440                                 if ( count( $headerParts ) == 1 ) {
 441                                         $headerArray[] = trim( $header );
 442                                 } else {
 443                                         list( $key, $val ) = $headerParts;
 444                                         $headerArray[trim( $key )] = trim( $val );
 445                                 }
 446                         }
 447                         $status->value = $headerArray;
 448                 } else {
 449                         # Don't return the text of error messages, return false on error
 450                         $retcode = curl_getinfo( $c, CURLINFO_HTTP_CODE );
 451                         if ( $retcode != 200 ) {
 452                                 wfDebug( __METHOD__ . ": HTTP return code $retcode\n" );
 453                                 $status = Status::newFatal( "HTTP return code $retcode\n" );
 454                         }
 455                         # Don't return truncated output
 456                         $errno = curl_errno( $c );
 457                         if ( $errno != CURLE_OK ) {
 458                                 $errstr = curl_error( $c );
 459                                 wfDebug( __METHOD__ . ": CURL error code $errno: $errstr\n" );
 460                                 $status = Status::newFatal( " CURL error code $errno: $errstr\n" );
 461                         }
 462                 }
 463
 464                 curl_close( $c );
 465
 466                 // return the result obj
 467                 return $status;
 468         }
 469
 470         public function doPhpReq(){
 471                 global $wgTitle, $wgHTTPProxy;
 472                 # Check for php.ini allow_url_fopen
 473                 if( !ini_get( 'allow_url_fopen' ) ){
 474                         return Status::newFatal( 'allow_url_fopen needs to be enabled for http copy to work' );
 475                 }
 476
 477                 // start with good status:
 478                 $status = Status::newGood();
 479
 480                 if ( $this->headers_only ) {
 481                         $status->value = get_headers( $this->url, 1 );
 482                         return $status;
 483                 }
 484
 485                 // setup the headers
 486                 $headers = array( "User-Agent: " . Http::userAgent() );
 487                 if ( is_object( $wgTitle ) ) {
 488                         $headers[] = "Referer: ". $wgTitle->getFullURL();
 489                 }
 490
 491                 if( strcasecmp( $this->method, 'post' ) == 0 ) {
 492                         // Required for HTTP 1.0 POSTs
 493                         $headers[] = "Content-Length: 0";
 494                 }
 495                 $fcontext = stream_context_create ( array(
 496                         'http' => array(
 497                                 'method' => $this->method,
 498                                 'header' => implode( "\r\n", $headers ),
 499                                 'timeout' => $this->timeout )
 500                         )
 501                 );
 502                 $fh = fopen( $this->url, "r", false, $fcontext);
 503
 504                 // set the write back function (if we are writing to a file)
 505                 if( $this->target_file_path ){
 506                         $cwrite = new simpleFileWriter( $this->target_file_path, $this->upload_session_key, $this->do_close_session_update );
 507                         if( !$cwrite->status->isOK() ){
 508                                 wfDebug( __METHOD__ . "ERROR in setting up simpleFileWriter\n" );
 509                                 $status = $cwrite->status;
 510                                 return $status;
 511                         }
 512
 513                         // read $fh into the simpleFileWriter (grab in 64K chunks since its likely a ~large~ media file)
 514                         while ( !feof( $fh ) ) {
 515                                 $contents = fread( $fh, 65536 );
 516                                 $cwrite->callbackWriteBody( $fh, $contents );
 517                         }
 518                         $cwrite->close();
 519                         // check for simpleFileWriter error:
 520                         if( !$cwrite->status->isOK() ){
 521                                 return $cwrite->status;
 522                         }
 523                 } else {
 524                         // read $fh into status->value
 525                         $status->value = @stream_get_contents( $fh );
 526                 }
 527                 //close the url file wrapper
 528                 fclose( $fh );
 529
 530                 // check for "false"
 531                 if( $status->value === false ){
 532                         $status->error( 'file_get_contents-failed' );
 533                 }
 534                 return $status;
 535         }
 536
 537 }
 538
 539 /**
 540  * a simpleFileWriter with session id updates
 541  */
 542 class simpleFileWriter {
 543         var $target_file_path;
 544         var $status = null;
 545         var $session_id = null;
 546         var $session_update_interval = 0; // how often to update the session while downloading
 547
 548         function simpleFileWriter( $target_file_path, $upload_session_key, $do_close_session_update = false ){
 549                 $this->target_file_path = $target_file_path;
 550                 $this->upload_session_key = $upload_session_key;
 551                 $this->status = Status::newGood();
 552                 $this->do_close_session_update = $do_close_session_update;
 553                 // open the file:
 554                 $this->fp = fopen( $this->target_file_path, 'w' );
 555                 if( $this->fp === false ){
 556                         $this->status = Status::newFatal( 'HTTP::could-not-open-file-for-writing' );
 557                 }
 558                 // true start time
 559                 $this->prevTime = time();
 560         }
 561
 562         public function callbackWriteBody( $ch, $data_packet ){
 563                 global $wgMaxUploadSize, $wgLang;
 564
 565                 // write out the content
 566                 if( fwrite( $this->fp, $data_packet ) === false ){
 567                         wfDebug( __METHOD__ ." ::could-not-write-to-file\n" );
 568                         $this->status = Status::newFatal( 'HTTP::could-not-write-to-file' );
 569                         return 0;
 570                 }
 571
 572                 // check file size:
 573                 clearstatcache();
 574                 $this->current_fsize = filesize( $this->target_file_path );
 575
 576                 if( $this->current_fsize > $wgMaxUploadSize ){
 577                         wfDebug( __METHOD__ . " ::http download too large\n" );
 578                         $this->status = Status::newFatal( 'HTTP::file-has-grown-beyond-upload-limit-killing: downloaded more than ' .
 579                                 $wgLang->formatSize( $wgMaxUploadSize ) . ' ' );
 580                         return 0;
 581                 }
 582                 // if more than session_update_interval second have passed update_session_progress
 583                 if( $this->do_close_session_update && $this->upload_session_key &&
 584                         ( ( time() - $this->prevTime ) > $this->session_update_interval ) ) {
 585                                 $this->prevTime = time();
 586                                 $session_status = $this->update_session_progress();
 587                                 if( !$session_status->isOK() ){
 588                                         $this->status = $session_status;
 589                                         wfDebug( __METHOD__ . ' update session failed or was canceled');
 590                                         return 0;
 591                                 }
 592                 }
 593                 return strlen( $data_packet );
 594         }
 595
 596         public function update_session_progress(){
 597                 global $wgSessionsInMemcached;
 598                 $status = Status::newGood();
 599                 // start the session (if necessary)
 600                 if( !$wgSessionsInMemcached ){
 601                         wfSuppressWarnings();
 602                         if( session_start() === false ){
 603                                 wfDebug( __METHOD__ . ' could not start session' );
 604                                 exit( 0 );
 605                         }
 606                         wfRestoreWarnings();
 607                 }
 608                 $sd =& $_SESSION['wsDownload'][ $this->upload_session_key ];
 609                 // check if the user canceled the request:
 610                 if( isset( $sd['user_cancel'] ) && $sd['user_cancel'] == true ){
 611                         //@@todo kill the download
 612                         return Status::newFatal( 'user-canceled-request' );
 613                 }
 614                 // update the progress bytes download so far:
 615                 $sd['loaded'] = $this->current_fsize;
 616
 617                 // close down the session so we can other http queries can get session updates:
 618                 if( !$wgSessionsInMemcached )
 619                         session_write_close();
 620
 621                 return $status;
 622         }
 623
 624         public function close(){
 625                 // do a final session update:
 626                 if( $this->do_close_session_update ){
 627                         $this->update_session_progress();
 628                 }
 629                 // close up the file handle:
 630                 if( false === fclose( $this->fp ) ){
 631                         $this->status = Status::newFatal( 'HTTP::could-not-close-file' );
 632                 }
 633         }
 634
 635 }