includes/filerepo/file/File.php

   1 <?php
   2 /**
   3  * Base code for files.
   4  *
   5  * @file
   6  * @ingroup FileRepo
   7  */
   8
   9 /**
  10  * Implements some public methods and some protected utility functions which
  11  * are required by multiple child classes. Contains stub functionality for
  12  * unimplemented public methods.
  13  *
  14  * Stub functions which should be overridden are marked with STUB. Some more
  15  * concrete functions are also typically overridden by child classes.
  16  *
  17  * Note that only the repo object knows what its file class is called. You should
  18  * never name a file class explictly outside of the repo class. Instead use the
  19  * repo's factory functions to generate file objects, for example:
  20  *
  21  * RepoGroup::singleton()->getLocalRepo()->newFile($title);
  22  *
  23  * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
  24  * in most cases.
  25  *
  26  * @ingroup FileRepo
  27  */
  28 abstract class File {
  29         const DELETED_FILE = 1;
  30         const DELETED_COMMENT = 2;
  31         const DELETED_USER = 4;
  32         const DELETED_RESTRICTED = 8;
  33
  34         /** Force rendering in the current process */
  35         const RENDER_NOW   = 1;
  36         /**
  37          * Force rendering even if thumbnail already exist and using RENDER_NOW
  38          * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
  39          */
  40         const RENDER_FORCE = 2;
  41
  42         const DELETE_SOURCE = 1;
  43
  44         /**
  45          * Some member variables can be lazy-initialised using __get(). The
  46          * initialisation function for these variables is always a function named
  47          * like getVar(), where Var is the variable name with upper-case first
  48          * letter.
  49          *
  50          * The following variables are initialised in this way in this base class:
  51          *    name, extension, handler, path, canRender, isSafeFile,
  52          *    transformScript, hashPath, pageCount, url
  53          *
  54          * Code within this class should generally use the accessor function
  55          * directly, since __get() isn't re-entrant and therefore causes bugs that
  56          * depend on initialisation order.
  57          */
  58
  59         /**
  60          * The following member variables are not lazy-initialised
  61          */
  62
  63         /**
  64          * @var FileRepo|false
  65          */
  66         var $repo;
  67
  68         /**
  69          * @var Title|false
  70          */
  71         var $title;
  72
  73         var $lastError, $redirected, $redirectedTitle;
  74
  75         /**
  76          * @var FSFile|false
  77          */
  78         protected $fsFile;
  79
  80         /**
  81          * @var MediaHandler
  82          */
  83         protected $handler;
  84
  85         /**
  86          * @var string
  87          */
  88         protected $url, $extension, $name, $path, $hashPath, $pageCount, $transformScript;
  89
  90         /**
  91          * @var bool
  92          */
  93         protected $canRender, $isSafeFile;
  94
  95         /**
  96          * @var string Required Repository class type
  97          */
  98         protected $repoClass = 'FileRepo';
  99
 100         /**
 101          * Call this constructor from child classes.
 102          *
 103          * Both $title and $repo are optional, though some functions
 104          * may return false or throw exceptions if they are not set.
 105          * Most subclasses will want to call assertRepoDefined() here.
 106          *
 107          * @param $title Title|string|false
 108          * @param $repo FileRepo|false
 109          */
 110         function __construct( $title, $repo ) {
 111                 if ( $title !== false ) { // subclasses may not use MW titles
 112                         $title = self::normalizeTitle( $title, 'exception' );
 113                 }
 114                 $this->title = $title;
 115                 $this->repo = $repo;
 116         }
 117
 118         /**
 119          * Given a string or Title object return either a
 120          * valid Title object with namespace NS_FILE or null
 121          *
 122          * @param $title Title|string
 123          * @param $exception string|false Use 'exception' to throw an error on bad titles
 124          * @return Title|null
 125          */
 126         static function normalizeTitle( $title, $exception = false ) {
 127                 $ret = $title;
 128                 if ( $ret instanceof Title ) {
 129                         # Normalize NS_MEDIA -> NS_FILE
 130                         if ( $ret->getNamespace() == NS_MEDIA ) {
 131                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 132                         # Sanity check the title namespace
 133                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 134                                 $ret = null;
 135                         }
 136                 } else {
 137                         # Convert strings to Title objects
 138                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 139                 }
 140                 if ( !$ret && $exception !== false ) {
 141                         throw new MWException( "`$title` is not a valid file title." );
 142                 }
 143                 return $ret;
 144         }
 145
 146         function __get( $name ) {
 147                 $function = array( $this, 'get' . ucfirst( $name ) );
 148                 if ( !is_callable( $function ) ) {
 149                         return null;
 150                 } else {
 151                         $this->$name = call_user_func( $function );
 152                         return $this->$name;
 153                 }
 154         }
 155
 156         /**
 157          * Normalize a file extension to the common form, and ensure it's clean.
 158          * Extensions with non-alphanumeric characters will be discarded.
 159          *
 160          * @param $ext string (without the .)
 161          * @return string
 162          */
 163         static function normalizeExtension( $ext ) {
 164                 $lower = strtolower( $ext );
 165                 $squish = array(
 166                         'htm' => 'html',
 167                         'jpeg' => 'jpg',
 168                         'mpeg' => 'mpg',
 169                         'tiff' => 'tif',
 170                         'ogv' => 'ogg' );
 171                 if( isset( $squish[$lower] ) ) {
 172                         return $squish[$lower];
 173                 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 174                         return $lower;
 175                 } else {
 176                         return '';
 177                 }
 178         }
 179
 180         /**
 181          * Checks if file extensions are compatible
 182          *
 183          * @param $old File Old file
 184          * @param $new string New name
 185          *
 186          * @return bool|null
 187          */
 188         static function checkExtensionCompatibility( File $old, $new ) {
 189                 $oldMime = $old->getMimeType();
 190                 $n = strrpos( $new, '.' );
 191                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 192                 $mimeMagic = MimeMagic::singleton();
 193                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 194         }
 195
 196         /**
 197          * Upgrade the database row if there is one
 198          * Called by ImagePage
 199          * STUB
 200          */
 201         function upgradeRow() {}
 202
 203         /**
 204          * Split an internet media type into its two components; if not
 205          * a two-part name, set the minor type to 'unknown'.
 206          *
 207          * @param string $mime "text/html" etc
 208          * @return array ("text", "html") etc
 209          */
 210         public static function splitMime( $mime ) {
 211                 if( strpos( $mime, '/' ) !== false ) {
 212                         return explode( '/', $mime, 2 );
 213                 } else {
 214                         return array( $mime, 'unknown' );
 215                 }
 216         }
 217
 218         /**
 219          * Return the name of this file
 220          *
 221          * @return string
 222          */
 223         public function getName() {
 224                 if ( !isset( $this->name ) ) {
 225                         $this->assertRepoDefined();
 226                         $this->name = $this->repo->getNameFromTitle( $this->title );
 227                 }
 228                 return $this->name;
 229         }
 230
 231         /**
 232          * Get the file extension, e.g. "svg"
 233          *
 234          * @return string
 235          */
 236         function getExtension() {
 237                 if ( !isset( $this->extension ) ) {
 238                         $n = strrpos( $this->getName(), '.' );
 239                         $this->extension = self::normalizeExtension(
 240                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 241                 }
 242                 return $this->extension;
 243         }
 244
 245         /**
 246          * Return the associated title object
 247          *
 248          * @return Title|false
 249          */
 250         public function getTitle() {
 251                 return $this->title;
 252         }
 253
 254         /**
 255          * Return the title used to find this file
 256          *
 257          * @return Title
 258          */
 259         public function getOriginalTitle() {
 260                 if ( $this->redirected ) {
 261                         return $this->getRedirectedTitle();
 262                 }
 263                 return $this->title;
 264         }
 265
 266         /**
 267          * Return the URL of the file
 268          *
 269          * @return string
 270          */
 271         public function getUrl() {
 272                 if ( !isset( $this->url ) ) {
 273                         $this->assertRepoDefined();
 274                         $this->url = $this->repo->getZoneUrl( 'public' ) . '/' . $this->getUrlRel();
 275                 }
 276                 return $this->url;
 277         }
 278
 279         /**
 280          * Return a fully-qualified URL to the file.
 281          * Upload URL paths _may or may not_ be fully qualified, so
 282          * we check. Local paths are assumed to belong on $wgServer.
 283          *
 284          * @return String
 285          */
 286         public function getFullUrl() {
 287                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 288         }
 289
 290         /**
 291          * @return string
 292          */
 293         public function getCanonicalUrl() {
 294                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 295         }
 296
 297         /**
 298          * @return string
 299          */
 300         function getViewURL() {
 301                 if( $this->mustRender()) {
 302                         if( $this->canRender() ) {
 303                                 return $this->createThumb( $this->getWidth() );
 304                         } else {
 305                                 wfDebug(__METHOD__.': supposed to render '.$this->getName().' ('.$this->getMimeType()."), but can't!\n");
 306                                 return $this->getURL(); #hm... return NULL?
 307                         }
 308                 } else {
 309                         return $this->getURL();
 310                 }
 311         }
 312
 313         /**
 314         * Return the storage path to the file. Note that this does
 315         * not mean that a file actually exists under that location.
 316         *
 317         * This path depends on whether directory hashing is active or not,
 318         * i.e. whether the files are all found in the same directory,
 319         * or in hashed paths like /images/3/3c.
 320         *
 321         * Most callers don't check the return value, but ForeignAPIFile::getPath
 322         * returns false.
 323          *
 324          * @return string|false
 325         */
 326         public function getPath() {
 327                 if ( !isset( $this->path ) ) {
 328                         $this->assertRepoDefined();
 329                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 330                 }
 331                 return $this->path;
 332         }
 333
 334         /**
 335          * Get an FS copy or original of this file and return the path.
 336          * Returns false on failure. Callers must not alter the file.
 337          * Temporary files are cleared automatically.
 338          *
 339          * @return string|false
 340          */
 341         public function getLocalRefPath() {
 342                 $this->assertRepoDefined();
 343                 if ( !isset( $this->fsFile ) ) {
 344                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 345                         if ( !$this->fsFile ) {
 346                                 $this->fsFile = false; // null => false; cache negative hits
 347                         }
 348                 }
 349                 return ( $this->fsFile )
 350                         ? $this->fsFile->getPath()
 351                         : false;
 352         }
 353
 354         /**
 355          * Return the width of the image. Returns false if the width is unknown
 356          * or undefined.
 357          *
 358          * STUB
 359          * Overridden by LocalFile, UnregisteredLocalFile
 360          *
 361          * @param $page int
 362          *
 363          * @return number
 364          */
 365         public function getWidth( $page = 1 ) {
 366                 return false;
 367         }
 368
 369         /**
 370          * Return the height of the image. Returns false if the height is unknown
 371          * or undefined
 372          *
 373          * STUB
 374          * Overridden by LocalFile, UnregisteredLocalFile
 375          *
 376          * @param $page int
 377          *
 378          * @return false|number
 379          */
 380         public function getHeight( $page = 1 ) {
 381                 return false;
 382         }
 383
 384         /**
 385          * Returns ID or name of user who uploaded the file
 386          * STUB
 387          *
 388          * @param $type string 'text' or 'id'
 389          *
 390          * @return string|int
 391          */
 392         public function getUser( $type = 'text' ) {
 393                 return null;
 394         }
 395
 396         /**
 397          * Get the duration of a media file in seconds
 398          *
 399          * @return number
 400          */
 401         public function getLength() {
 402                 $handler = $this->getHandler();
 403                 if ( $handler ) {
 404                         return $handler->getLength( $this );
 405                 } else {
 406                         return 0;
 407                 }
 408         }
 409
 410         /**
 411          * Return true if the file is vectorized
 412          *
 413          * @return bool
 414          */
 415         public function isVectorized() {
 416                 $handler = $this->getHandler();
 417                 if ( $handler ) {
 418                         return $handler->isVectorized( $this );
 419                 } else {
 420                         return false;
 421                 }
 422         }
 423
 424         /**
 425          * Get handler-specific metadata
 426          * Overridden by LocalFile, UnregisteredLocalFile
 427          * STUB
 428          */
 429         public function getMetadata() {
 430                 return false;
 431         }
 432
 433         /**
 434         * get versioned metadata
 435         *
 436         * @param $metadata Mixed Array or String of (serialized) metadata
 437         * @param $version integer version number.
 438         * @return Array containing metadata, or what was passed to it on fail (unserializing if not array)
 439         */
 440         public function convertMetadataVersion($metadata, $version) {
 441                 $handler = $this->getHandler();
 442                 if ( !is_array( $metadata ) ) {
 443                         // Just to make the return type consistent
 444                         $metadata = unserialize( $metadata );
 445                 }
 446                 if ( $handler ) {
 447                         return $handler->convertMetadataVersion( $metadata, $version );
 448                 } else {
 449                         return $metadata;
 450                 }
 451         }
 452
 453         /**
 454          * Return the bit depth of the file
 455          * Overridden by LocalFile
 456          * STUB
 457          */
 458         public function getBitDepth() {
 459                 return 0;
 460         }
 461
 462         /**
 463          * Return the size of the image file, in bytes
 464          * Overridden by LocalFile, UnregisteredLocalFile
 465          * STUB
 466          */
 467         public function getSize() {
 468                 return false;
 469         }
 470
 471         /**
 472          * Returns the mime type of the file.
 473          * Overridden by LocalFile, UnregisteredLocalFile
 474          * STUB
 475          *
 476          * @return string
 477          */
 478         function getMimeType() {
 479                 return 'unknown/unknown';
 480         }
 481
 482         /**
 483          * Return the type of the media in the file.
 484          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 485          * Overridden by LocalFile,
 486          * STUB
 487          */
 488         function getMediaType() {
 489                 return MEDIATYPE_UNKNOWN;
 490         }
 491
 492         /**
 493          * Checks if the output of transform() for this file is likely
 494          * to be valid. If this is false, various user elements will
 495          * display a placeholder instead.
 496          *
 497          * Currently, this checks if the file is an image format
 498          * that can be converted to a format
 499          * supported by all browsers (namely GIF, PNG and JPEG),
 500          * or if it is an SVG image and SVG conversion is enabled.
 501          *
 502          * @return bool
 503          */
 504         function canRender() {
 505                 if ( !isset( $this->canRender ) ) {
 506                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 507                 }
 508                 return $this->canRender;
 509         }
 510
 511         /**
 512          * Accessor for __get()
 513          */
 514         protected function getCanRender() {
 515                 return $this->canRender();
 516         }
 517
 518         /**
 519          * Return true if the file is of a type that can't be directly
 520          * rendered by typical browsers and needs to be re-rasterized.
 521          *
 522          * This returns true for everything but the bitmap types
 523          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 524          * also return true for any non-image formats.
 525          *
 526          * @return bool
 527          */
 528         function mustRender() {
 529                 return $this->getHandler() && $this->handler->mustRender( $this );
 530         }
 531
 532         /**
 533          * Alias for canRender()
 534          *
 535          * @return bool
 536          */
 537         function allowInlineDisplay() {
 538                 return $this->canRender();
 539         }
 540
 541         /**
 542          * Determines if this media file is in a format that is unlikely to
 543          * contain viruses or malicious content. It uses the global
 544          * $wgTrustedMediaFormats list to determine if the file is safe.
 545          *
 546          * This is used to show a warning on the description page of non-safe files.
 547          * It may also be used to disallow direct [[media:...]] links to such files.
 548          *
 549          * Note that this function will always return true if allowInlineDisplay()
 550          * or isTrustedFile() is true for this file.
 551          *
 552          * @return bool
 553          */
 554         function isSafeFile() {
 555                 if ( !isset( $this->isSafeFile ) ) {
 556                         $this->isSafeFile = $this->_getIsSafeFile();
 557                 }
 558                 return $this->isSafeFile;
 559         }
 560
 561         /**
 562          * Accessor for __get()
 563          *
 564          * @return bool
 565          */
 566         protected function getIsSafeFile() {
 567                 return $this->isSafeFile();
 568         }
 569
 570         /**
 571          * Uncached accessor
 572          *
 573          * @return bool
 574          */
 575         protected function _getIsSafeFile() {
 576                 global $wgTrustedMediaFormats;
 577
 578                 if ( $this->allowInlineDisplay() ) {
 579                         return true;
 580                 }
 581                 if ($this->isTrustedFile()) {
 582                         return true;
 583                 }
 584
 585                 $type = $this->getMediaType();
 586                 $mime = $this->getMimeType();
 587                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 588
 589                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 590                         return false; #unknown type, not trusted
 591                 }
 592                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 593                         return true;
 594                 }
 595
 596                 if ( $mime === "unknown/unknown" ) {
 597                         return false; #unknown type, not trusted
 598                 }
 599                 if ( in_array( $mime, $wgTrustedMediaFormats) ) {
 600                         return true;
 601                 }
 602
 603                 return false;
 604         }
 605
 606         /**
 607          * Returns true if the file is flagged as trusted. Files flagged that way
 608          * can be linked to directly, even if that is not allowed for this type of
 609          * file normally.
 610          *
 611          * This is a dummy function right now and always returns false. It could be
 612          * implemented to extract a flag from the database. The trusted flag could be
 613          * set on upload, if the user has sufficient privileges, to bypass script-
 614          * and html-filters. It may even be coupled with cryptographics signatures
 615          * or such.
 616          *
 617          * @return bool
 618          */
 619         function isTrustedFile() {
 620                 #this could be implemented to check a flag in the database,
 621                 #look for signatures, etc
 622                 return false;
 623         }
 624
 625         /**
 626          * Returns true if file exists in the repository.
 627          *
 628          * Overridden by LocalFile to avoid unnecessary stat calls.
 629          *
 630          * @return boolean Whether file exists in the repository.
 631          */
 632         public function exists() {
 633                 return $this->getPath() && $this->repo->fileExists( $this->path );
 634         }
 635
 636         /**
 637          * Returns true if file exists in the repository and can be included in a page.
 638          * It would be unsafe to include private images, making public thumbnails inadvertently
 639          *
 640          * @return boolean Whether file exists in the repository and is includable.
 641          */
 642         public function isVisible() {
 643                 return $this->exists();
 644         }
 645
 646         /**
 647          * @return string
 648          */
 649         function getTransformScript() {
 650                 if ( !isset( $this->transformScript ) ) {
 651                         $this->transformScript = false;
 652                         if ( $this->repo ) {
 653                                 $script = $this->repo->getThumbScriptUrl();
 654                                 if ( $script ) {
 655                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 656                                 }
 657                         }
 658                 }
 659                 return $this->transformScript;
 660         }
 661
 662         /**
 663          * Get a ThumbnailImage which is the same size as the source
 664          *
 665          * @param $handlerParams array
 666          *
 667          * @return string
 668          */
 669         function getUnscaledThumb( $handlerParams = array() ) {
 670                 $hp =& $handlerParams;
 671                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 672                 $width = $this->getWidth( $page );
 673                 if ( !$width ) {
 674                         return $this->iconThumb();
 675                 }
 676                 $hp['width'] = $width;
 677                 return $this->transform( $hp );
 678         }
 679
 680         /**
 681          * Return the file name of a thumbnail with the specified parameters
 682          *
 683          * @param $params Array: handler-specific parameters
 684          * @private -ish
 685          *
 686          * @return string
 687          */
 688         function thumbName( $params ) {
 689                 return $this->generateThumbName( $this->getName(), $params );
 690         }
 691
 692         /**
 693          * Generate a thumbnail file name from a name and specified parameters
 694          *
 695          * @param string $name
 696          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 697          *
 698          * @return string
 699          */
 700         function generateThumbName( $name, $params ) {
 701                 if ( !$this->getHandler() ) {
 702                         return null;
 703                 }
 704                 $extension = $this->getExtension();
 705                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
 706                         $extension, $this->getMimeType(), $params );
 707                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 708                 if ( $thumbExt != $extension ) {
 709                         $thumbName .= ".$thumbExt";
 710                 }
 711                 return $thumbName;
 712         }
 713
 714         /**
 715          * Create a thumbnail of the image having the specified width/height.
 716          * The thumbnail will not be created if the width is larger than the
 717          * image's width. Let the browser do the scaling in this case.
 718          * The thumbnail is stored on disk and is only computed if the thumbnail
 719          * file does not exist OR if it is older than the image.
 720          * Returns the URL.
 721          *
 722          * Keeps aspect ratio of original image. If both width and height are
 723          * specified, the generated image will be no bigger than width x height,
 724          * and will also have correct aspect ratio.
 725          *
 726          * @param $width Integer: maximum width of the generated thumbnail
 727          * @param $height Integer: maximum height of the image (optional)
 728          *
 729          * @return string
 730          */
 731         public function createThumb( $width, $height = -1 ) {
 732                 $params = array( 'width' => $width );
 733                 if ( $height != -1 ) {
 734                         $params['height'] = $height;
 735                 }
 736                 $thumb = $this->transform( $params );
 737                 if ( is_null( $thumb ) || $thumb->isError() ) {
 738                         return '';
 739                 }
 740                 return $thumb->getUrl();
 741         }
 742
 743         /**
 744          * Do the work of a transform (from an original into a thumb).
 745          * Contains filesystem-specific functions.
 746          *
 747          * @param $thumbName string: the name of the thumbnail file.
 748          * @param $thumbUrl string: the URL of the thumbnail file.
 749          * @param $params Array: an associative array of handler-specific parameters.
 750          *                Typical keys are width, height and page.
 751          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 752          *
 753          * @return MediaTransformOutput|null
 754          */
 755         protected function maybeDoTransform( $thumbName, $thumbUrl, $params, $flags = 0 ) {
 756                 global $wgIgnoreImageErrors, $wgThumbnailEpoch;
 757
 758                 $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
 759                 if ( $this->repo && $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
 760                         wfDebug( __METHOD__ . " transformation deferred." );
 761                         // XXX: Pass in the storage path even though we are not rendering anything
 762                         // and the path is supposed to be an FS path. This is due to getScalerType()
 763                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
 764                         return $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 765                 }
 766
 767                 wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
 768                 $this->migrateThumbFile( $thumbName );
 769                 if ( $this->repo->fileExists( $thumbPath ) && !( $flags & self::RENDER_FORCE ) ) {
 770                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
 771                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
 772                                 // XXX: Pass in the storage path even though we are not rendering anything
 773                                 // and the path is supposed to be an FS path. This is due to getScalerType()
 774                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
 775                                 return $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 776                         }
 777                 } elseif ( $flags & self::RENDER_FORCE ) {
 778                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
 779                 }
 780
 781                 // Create a temp FS file with the same extension and the thumbnail
 782                 $extension = $this->getExtension();
 783                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
 784                         $extension, $this->getMimeType(), $params );
 785                 $tmpFile = TempFSFile::factory( 'transform_', FileBackend::extensionFromPath( $thumbPath ) );
 786                 if ( !$tmpFile ) {
 787                         return new MediaTransformError( 'thumbnail_error',
 788                                 $params['width'], 0, wfMsg( 'thumbnail-temp-create' ) );
 789                 }
 790                 $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
 791
 792                 // Actually render the thumbnail
 793                 $thumb = $this->handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 794                 $tmpFile->bind( $thumb ); // keep alive with $thumb
 795
 796                 // Ignore errors if requested
 797                 if ( !$thumb ) {
 798                         $thumb = null;
 799                 } elseif ( $thumb->isError() ) {
 800                         $this->lastError = $thumb->toText();
 801                         if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 802                                 $thumb = $this->handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 803                         }
 804                 } elseif ( $thumb->hasFile() && !$thumb->fileIsSource() ) {
 805                         // Copy any thumbnail from the FS into storage at $dstpath
 806                         $status = $this->repo->store(
 807                                 $tmpThumbPath, 'thumb', $this->getThumbRel( $thumbName ),
 808                                 FileRepo::OVERWRITE | FileRepo::SKIP_LOCKING | FileRepo::ALLOW_STALE );
 809                         if ( !$status->isOK() ) {
 810                                 return new MediaTransformError( 'thumbnail_error',
 811                                         $params['width'], 0, wfMsg( 'thumbnail-dest-create' ) );
 812                         }
 813                 }
 814
 815                 return $thumb;
 816         }
 817
 818         /**
 819          * Transform a media file
 820          *
 821          * @param $params Array: an associative array of handler-specific parameters.
 822          *                Typical keys are width, height and page.
 823          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 824          * @return MediaTransformOutput | false
 825          */
 826         function transform( $params, $flags = 0 ) {
 827                 global $wgUseSquid;
 828
 829                 wfProfileIn( __METHOD__ );
 830                 do {
 831                         if ( !$this->canRender() ) {
 832                                 // not a bitmap or renderable image, don't try.
 833                                 $thumb = $this->iconThumb();
 834                                 break;
 835                         }
 836
 837                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 838                         $descriptionUrl =  $this->getDescriptionUrl();
 839                         if ( $descriptionUrl ) {
 840                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
 841                         }
 842
 843                         $script = $this->getTransformScript();
 844                         if ( $script && !($flags & self::RENDER_NOW) ) {
 845                                 // Use a script to transform on client request, if possible
 846                                 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
 847                                 if( $thumb ) {
 848                                         break;
 849                                 }
 850                         }
 851
 852                         $normalisedParams = $params;
 853                         $this->handler->normaliseParams( $this, $normalisedParams );
 854                         $thumbName = $this->thumbName( $normalisedParams );
 855                         $thumbUrl = $this->getThumbUrl( $thumbName );
 856
 857                         $thumb = $this->maybeDoTransform( $thumbName, $thumbUrl, $params, $flags );
 858
 859                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 860                         // purge collisions from elsewhere during failure. Don't keep triggering for
 861                         // "thumbs" which have the main image URL though (bug 13776)
 862                         if ( $wgUseSquid ) {
 863                                 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
 864                                         SquidUpdate::purge( array( $thumbUrl ) );
 865                                 }
 866                         }
 867                 } while (false);
 868
 869                 wfProfileOut( __METHOD__ );
 870                 return is_object( $thumb ) ? $thumb : false;
 871         }
 872
 873         /**
 874          * Hook into transform() to allow migration of thumbnail files
 875          * STUB
 876          * Overridden by LocalFile
 877          */
 878         function migrateThumbFile( $thumbName ) {}
 879
 880         /**
 881          * Get a MediaHandler instance for this file
 882          *
 883          * @return MediaHandler
 884          */
 885         function getHandler() {
 886                 if ( !isset( $this->handler ) ) {
 887                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
 888                 }
 889                 return $this->handler;
 890         }
 891
 892         /**
 893          * Get a ThumbnailImage representing a file type icon
 894          *
 895          * @return ThumbnailImage
 896          */
 897         function iconThumb() {
 898                 global $wgStylePath, $wgStyleDirectory;
 899
 900                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
 901                 foreach ( $try as $icon ) {
 902                         $path = '/common/images/icons/' . $icon;
 903                         $filepath = $wgStyleDirectory . $path;
 904                         if ( file_exists( $filepath ) ) { // always FS
 905                                 return new ThumbnailImage( $this, $wgStylePath . $path, 120, 120 );
 906                         }
 907                 }
 908                 return null;
 909         }
 910
 911         /**
 912          * Get last thumbnailing error.
 913          * Largely obsolete.
 914          */
 915         function getLastError() {
 916                 return $this->lastError;
 917         }
 918
 919         /**
 920          * Get all thumbnail names previously generated for this file
 921          * STUB
 922          * Overridden by LocalFile
 923          */
 924         function getThumbnails() {
 925                 return array();
 926         }
 927
 928         /**
 929          * Purge shared caches such as thumbnails and DB data caching
 930          * STUB
 931          * Overridden by LocalFile
 932          * @param $options Array Options, which include:
 933          *     'forThumbRefresh' : The purging is only to refresh thumbnails
 934          */
 935         function purgeCache( $options = array() ) {}
 936
 937         /**
 938          * Purge the file description page, but don't go after
 939          * pages using the file. Use when modifying file history
 940          * but not the current data.
 941          */
 942         function purgeDescription() {
 943                 $title = $this->getTitle();
 944                 if ( $title ) {
 945                         $title->invalidateCache();
 946                         $title->purgeSquid();
 947                 }
 948         }
 949
 950         /**
 951          * Purge metadata and all affected pages when the file is created,
 952          * deleted, or majorly updated.
 953          */
 954         function purgeEverything() {
 955                 // Delete thumbnails and refresh file metadata cache
 956                 $this->purgeCache();
 957                 $this->purgeDescription();
 958
 959                 // Purge cache of all pages using this file
 960                 $title = $this->getTitle();
 961                 if ( $title ) {
 962                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
 963                         $update->doUpdate();
 964                 }
 965         }
 966
 967         /**
 968          * Return a fragment of the history of file.
 969          *
 970          * STUB
 971          * @param $limit integer Limit of rows to return
 972          * @param $start timestamp Only revisions older than $start will be returned
 973          * @param $end timestamp Only revisions newer than $end will be returned
 974          * @param $inc bool Include the endpoints of the time range
 975          *
 976          * @return array
 977          */
 978         function getHistory($limit = null, $start = null, $end = null, $inc=true) {
 979                 return array();
 980         }
 981
 982         /**
 983          * Return the history of this file, line by line. Starts with current version,
 984          * then old versions. Should return an object similar to an image/oldimage
 985          * database row.
 986          *
 987          * STUB
 988          * Overridden in LocalFile
 989          */
 990         public function nextHistoryLine() {
 991                 return false;
 992         }
 993
 994         /**
 995          * Reset the history pointer to the first element of the history.
 996          * Always call this function after using nextHistoryLine() to free db resources
 997          * STUB
 998          * Overridden in LocalFile.
 999          */
1000         public function resetHistory() {}
1001
1002         /**
1003          * Get the filename hash component of the directory including trailing slash,
1004          * e.g. f/fa/
1005          * If the repository is not hashed, returns an empty string.
1006          *
1007          * @return string
1008          */
1009         function getHashPath() {
1010                 if ( !isset( $this->hashPath ) ) {
1011                         $this->assertRepoDefined();
1012                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1013                 }
1014                 return $this->hashPath;
1015         }
1016
1017         /**
1018          * Get the path of the file relative to the public zone root.
1019          * This function is overriden in OldLocalFile to be like getArchiveRel().
1020          *
1021          * @return string
1022          */
1023         function getRel() {
1024                 return $this->getHashPath() . $this->getName();
1025         }
1026
1027         /**
1028          * Get the path of an archived file relative to the public zone root
1029          *
1030          * @param $suffix bool|string if not false, the name of an archived thumbnail file
1031          *
1032          * @return string
1033          */
1034         function getArchiveRel( $suffix = false ) {
1035                 $path = 'archive/' . $this->getHashPath();
1036                 if ( $suffix === false ) {
1037                         $path = substr( $path, 0, -1 );
1038                 } else {
1039                         $path .= $suffix;
1040                 }
1041                 return $path;
1042         }
1043
1044         /**
1045          * Get the path, relative to the thumbnail zone root, of the
1046          * thumbnail directory or a particular file if $suffix is specified
1047          *
1048          * @param $suffix bool|string if not false, the name of a thumbnail file
1049          *
1050          * @return string
1051          */
1052         function getThumbRel( $suffix = false ) {
1053                 $path = $this->getRel();
1054                 if ( $suffix !== false ) {
1055                         $path .= '/' . $suffix;
1056                 }
1057                 return $path;
1058         }
1059
1060         /**
1061          * Get urlencoded path of the file relative to the public zone root.
1062          * This function is overriden in OldLocalFile to be like getArchiveUrl().
1063          *
1064          * @return string
1065          */
1066         function getUrlRel() {
1067                 return $this->getHashPath() . rawurlencode( $this->getName() );
1068         }
1069
1070         /**
1071          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1072          * or a specific thumb if the $suffix is given.
1073          *
1074          * @param $archiveName string the timestamped name of an archived image
1075          * @param $suffix bool|string if not false, the name of a thumbnail file
1076          *
1077          * @return string
1078          */
1079         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1080                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1081                 if ( $suffix === false ) {
1082                         $path = substr( $path, 0, -1 );
1083                 } else {
1084                         $path .= $suffix;
1085                 }
1086                 return $path;
1087         }
1088
1089         /**
1090          * Get the path of the archived file.
1091          *
1092          * @param $suffix bool|string if not false, the name of an archived file.
1093          *
1094          * @return string
1095          */
1096         function getArchivePath( $suffix = false ) {
1097                 $this->assertRepoDefined();
1098                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1099         }
1100
1101         /**
1102          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1103          *
1104          * @param $archiveName string the timestamped name of an archived image
1105          * @param $suffix bool|string if not false, the name of a thumbnail file
1106          *
1107          * @return string
1108          */
1109         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1110                 $this->assertRepoDefined();
1111                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1112                         $this->getArchiveThumbRel( $archiveName, $suffix );
1113         }
1114
1115         /**
1116          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1117          *
1118          * @param $suffix bool|string if not false, the name of a thumbnail file
1119          *
1120          * @return string
1121          */
1122         function getThumbPath( $suffix = false ) {
1123                 $this->assertRepoDefined();
1124                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1125         }
1126
1127         /**
1128          * Get the URL of the archive directory, or a particular file if $suffix is specified
1129          *
1130          * @param $suffix bool|string if not false, the name of an archived file
1131          *
1132          * @return string
1133          */
1134         function getArchiveUrl( $suffix = false ) {
1135                 $this->assertRepoDefined();
1136                 $path = $this->repo->getZoneUrl( 'public' ) . '/archive/' . $this->getHashPath();
1137                 if ( $suffix === false ) {
1138                         $path = substr( $path, 0, -1 );
1139                 } else {
1140                         $path .= rawurlencode( $suffix );
1141                 }
1142                 return $path;
1143         }
1144
1145         /**
1146          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1147          *
1148          * @param $archiveName string the timestamped name of an archived image
1149          * @param $suffix bool|string if not false, the name of a thumbnail file
1150          *
1151          * @return string
1152          */
1153         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1154                 $this->assertRepoDefined();
1155                 $path = $this->repo->getZoneUrl( 'thumb' ) . '/archive/' .
1156                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1157                 if ( $suffix === false ) {
1158                         $path = substr( $path, 0, -1 );
1159                 } else {
1160                         $path .= rawurlencode( $suffix );
1161                 }
1162                 return $path;
1163         }
1164
1165         /**
1166          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1167          *
1168          * @param $suffix bool|string if not false, the name of a thumbnail file
1169          *
1170          * @return path
1171          */
1172         function getThumbUrl( $suffix = false ) {
1173                 $this->assertRepoDefined();
1174                 $path = $this->repo->getZoneUrl( 'thumb' ) . '/' . $this->getUrlRel();
1175                 if ( $suffix !== false ) {
1176                         $path .= '/' . rawurlencode( $suffix );
1177                 }
1178                 return $path;
1179         }
1180
1181         /**
1182          * Get the public zone virtual URL for a current version source file
1183          *
1184          * @param $suffix bool|string if not false, the name of a thumbnail file
1185          *
1186          * @return string
1187          */
1188         function getVirtualUrl( $suffix = false ) {
1189                 $this->assertRepoDefined();
1190                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1191                 if ( $suffix !== false ) {
1192                         $path .= '/' . rawurlencode( $suffix );
1193                 }
1194                 return $path;
1195         }
1196
1197         /**
1198          * Get the public zone virtual URL for an archived version source file
1199          *
1200          * @param $suffix bool|string if not false, the name of a thumbnail file
1201          *
1202          * @return string
1203          */
1204         function getArchiveVirtualUrl( $suffix = false ) {
1205                 $this->assertRepoDefined();
1206                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1207                 if ( $suffix === false ) {
1208                         $path = substr( $path, 0, -1 );
1209                 } else {
1210                         $path .= rawurlencode( $suffix );
1211                 }
1212                 return $path;
1213         }
1214
1215         /**
1216          * Get the virtual URL for a thumbnail file or directory
1217          *
1218          * @param $suffix bool|string if not false, the name of a thumbnail file
1219          *
1220          * @return string
1221          */
1222         function getThumbVirtualUrl( $suffix = false ) {
1223                 $this->assertRepoDefined();
1224                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1225                 if ( $suffix !== false ) {
1226                         $path .= '/' . rawurlencode( $suffix );
1227                 }
1228                 return $path;
1229         }
1230
1231         /**
1232          * @return bool
1233          */
1234         function isHashed() {
1235                 $this->assertRepoDefined();
1236                 return $this->repo->isHashed();
1237         }
1238
1239         /**
1240          * @throws MWException
1241          */
1242         function readOnlyError() {
1243                 throw new MWException( get_class($this) . ': write operations are not supported' );
1244         }
1245
1246         /**
1247          * Record a file upload in the upload log and the image table
1248          * STUB
1249          * Overridden by LocalFile
1250          * @param $oldver
1251          * @param $desc
1252          * @param $license string
1253          * @param $copyStatus string
1254          * @param $source string
1255          * @param $watch bool
1256          */
1257         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
1258                 $this->readOnlyError();
1259         }
1260
1261         /**
1262          * Move or copy a file to its public location. If a file exists at the
1263          * destination, move it to an archive. Returns a FileRepoStatus object with
1264          * the archive name in the "value" member on success.
1265          *
1266          * The archive name should be passed through to recordUpload for database
1267          * registration.
1268          *
1269          * @param $srcPath String: local filesystem path to the source image
1270          * @param $flags Integer: a bitwise combination of:
1271          *     File::DELETE_SOURCE    Delete the source file, i.e. move
1272          *         rather than copy
1273          * @return FileRepoStatus object. On success, the value member contains the
1274          *     archive name, or an empty string if it was a new file.
1275          *
1276          * STUB
1277          * Overridden by LocalFile
1278          */
1279         function publish( $srcPath, $flags = 0 ) {
1280                 $this->readOnlyError();
1281         }
1282
1283         /**
1284          * @return bool
1285          */
1286         function formatMetadata() {
1287                 if ( !$this->getHandler() ) {
1288                         return false;
1289                 }
1290                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1291         }
1292
1293         /**
1294          * Returns true if the file comes from the local file repository.
1295          *
1296          * @return bool
1297          */
1298         function isLocal() {
1299                 return $this->repo && $this->repo->isLocal();
1300         }
1301
1302         /**
1303          * Returns the name of the repository.
1304          *
1305          * @return string
1306          */
1307         function getRepoName() {
1308                 return $this->repo ? $this->repo->getName() : 'unknown';
1309         }
1310
1311         /**
1312          * Returns the repository
1313          *
1314          * @return FileRepo|false
1315          */
1316         function getRepo() {
1317                 return $this->repo;
1318         }
1319
1320         /**
1321          * Returns true if the image is an old version
1322          * STUB
1323          *
1324          * @return bool
1325          */
1326         function isOld() {
1327                 return false;
1328         }
1329
1330         /**
1331          * Is this file a "deleted" file in a private archive?
1332          * STUB
1333          *
1334          * @param $field
1335          *
1336          * @return bool
1337          */
1338         function isDeleted( $field ) {
1339                 return false;
1340         }
1341
1342         /**
1343          * Return the deletion bitfield
1344          * STUB
1345          */
1346         function getVisibility() {
1347                 return 0;
1348         }
1349
1350         /**
1351          * Was this file ever deleted from the wiki?
1352          *
1353          * @return bool
1354          */
1355         function wasDeleted() {
1356                 $title = $this->getTitle();
1357                 return $title && $title->isDeletedQuick();
1358         }
1359
1360         /**
1361          * Move file to the new title
1362          *
1363          * Move current, old version and all thumbnails
1364          * to the new filename. Old file is deleted.
1365          *
1366          * Cache purging is done; checks for validity
1367          * and logging are caller's responsibility
1368          *
1369          * @param $target Title New file name
1370          * @return FileRepoStatus object.
1371          */
1372          function move( $target ) {
1373                 $this->readOnlyError();
1374          }
1375
1376         /**
1377          * Delete all versions of the file.
1378          *
1379          * Moves the files into an archive directory (or deletes them)
1380          * and removes the database rows.
1381          *
1382          * Cache purging is done; logging is caller's responsibility.
1383          *
1384          * @param $reason String
1385          * @param $suppress Boolean: hide content from sysops?
1386          * @return true on success, false on some kind of failure
1387          * STUB
1388          * Overridden by LocalFile
1389          */
1390         function delete( $reason, $suppress = false ) {
1391                 $this->readOnlyError();
1392         }
1393
1394         /**
1395          * Restore all or specified deleted revisions to the given file.
1396          * Permissions and logging are left to the caller.
1397          *
1398          * May throw database exceptions on error.
1399          *
1400          * @param $versions array set of record ids of deleted items to restore,
1401          *                    or empty to restore all revisions.
1402          * @param $unsuppress bool remove restrictions on content upon restoration?
1403          * @return int|false the number of file revisions restored if successful,
1404          *         or false on failure
1405          * STUB
1406          * Overridden by LocalFile
1407          */
1408         function restore( $versions = array(), $unsuppress = false ) {
1409                 $this->readOnlyError();
1410         }
1411
1412         /**
1413          * Returns 'true' if this file is a type which supports multiple pages,
1414          * e.g. DJVU or PDF. Note that this may be true even if the file in
1415          * question only has a single page.
1416          *
1417          * @return Bool
1418          */
1419         function isMultipage() {
1420                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1421         }
1422
1423         /**
1424          * Returns the number of pages of a multipage document, or false for
1425          * documents which aren't multipage documents
1426          *
1427          * @return false|int
1428          */
1429         function pageCount() {
1430                 if ( !isset( $this->pageCount ) ) {
1431                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1432                                 $this->pageCount = $this->handler->pageCount( $this );
1433                         } else {
1434                                 $this->pageCount = false;
1435                         }
1436                 }
1437                 return $this->pageCount;
1438         }
1439
1440         /**
1441          * Calculate the height of a thumbnail using the source and destination width
1442          *
1443          * @param $srcWidth
1444          * @param $srcHeight
1445          * @param $dstWidth
1446          *
1447          * @return int
1448          */
1449         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1450                 // Exact integer multiply followed by division
1451                 if ( $srcWidth == 0 ) {
1452                         return 0;
1453                 } else {
1454                         return round( $srcHeight * $dstWidth / $srcWidth );
1455                 }
1456         }
1457
1458         /**
1459          * Get an image size array like that returned by getImageSize(), or false if it
1460          * can't be determined.
1461          *
1462          * @param $fileName String: The filename
1463          * @return Array
1464          */
1465         function getImageSize( $fileName ) {
1466                 if ( !$this->getHandler() ) {
1467                         return false;
1468                 }
1469                 return $this->handler->getImageSize( $this, $fileName );
1470         }
1471
1472         /**
1473          * Get the URL of the image description page. May return false if it is
1474          * unknown or not applicable.
1475          *
1476          * @return string
1477          */
1478         function getDescriptionUrl() {
1479                 if ( $this->repo ) {
1480                         return $this->repo->getDescriptionUrl( $this->getName() );
1481                 } else {
1482                         return false;
1483                 }
1484         }
1485
1486         /**
1487          * Get the HTML text of the description page, if available
1488          *
1489          * @return string
1490          */
1491         function getDescriptionText() {
1492                 global $wgMemc, $wgLang;
1493                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1494                         return false;
1495                 }
1496                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1497                 if ( $renderUrl ) {
1498                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1499                                 wfDebug("Attempting to get the description from cache...");
1500                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1501                                                                         $this->getName() );
1502                                 $obj = $wgMemc->get($key);
1503                                 if ($obj) {
1504                                         wfDebug("success!\n");
1505                                         return $obj;
1506                                 }
1507                                 wfDebug("miss\n");
1508                         }
1509                         wfDebug( "Fetching shared description from $renderUrl\n" );
1510                         $res = Http::get( $renderUrl );
1511                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1512                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1513                         }
1514                         return $res;
1515                 } else {
1516                         return false;
1517                 }
1518         }
1519
1520         /**
1521          * Get discription of file revision
1522          * STUB
1523          *
1524          * @return string
1525          */
1526         function getDescription() {
1527                 return null;
1528         }
1529
1530         /**
1531          * Get the 14-character timestamp of the file upload
1532          *
1533          * @return string|false TS_MW timestamp or false on failure
1534          */
1535         function getTimestamp() {
1536                 $this->assertRepoDefined();
1537                 return $this->repo->getFileTimestamp( $this->getPath() );
1538         }
1539
1540         /**
1541          * Get the SHA-1 base 36 hash of the file
1542          *
1543          * @return string
1544          */
1545         function getSha1() {
1546                 $this->assertRepoDefined();
1547                 return $this->repo->getFileSha1( $this->getPath() );
1548         }
1549
1550         /**
1551          * Get the deletion archive key, <sha1>.<ext>
1552          *
1553          * @return string
1554          */
1555         function getStorageKey() {
1556                 $hash = $this->getSha1();
1557                 if ( !$hash ) {
1558                         return false;
1559                 }
1560                 $ext = $this->getExtension();
1561                 $dotExt = $ext === '' ? '' : ".$ext";
1562                 return $hash . $dotExt;
1563         }
1564
1565         /**
1566          * Determine if the current user is allowed to view a particular
1567          * field of this file, if it's marked as deleted.
1568          * STUB
1569          * @param $field Integer
1570          * @param $user User object to check, or null to use $wgUser
1571          * @return Boolean
1572          */
1573         function userCan( $field, User $user = null ) {
1574                 return true;
1575         }
1576
1577         /**
1578          * Get an associative array containing information about a file in the local filesystem.
1579          *
1580          * @param $path String: absolute local filesystem path
1581          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1582          *             Set it to false to ignore the extension.
1583          *
1584          * @return array
1585          */
1586         static function getPropsFromPath( $path, $ext = true ) {
1587                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1588                 wfDeprecated( __METHOD__, '1.19' );
1589
1590                 $fsFile = new FSFile( $path );
1591                 return $fsFile->getProps();
1592         }
1593
1594         /**
1595          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1596          * encoding, zero padded to 31 digits.
1597          *
1598          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1599          * fairly neatly.
1600          *
1601          * @param $path string
1602          *
1603          * @return false|string False on failure
1604          */
1605         static function sha1Base36( $path ) {
1606                 wfDeprecated( __METHOD__, '1.19' );
1607
1608                 $fsFile = new FSFile( $path );
1609                 return $fsFile->getSha1Base36();
1610         }
1611
1612         /**
1613          * @return string
1614          */
1615         function getLongDesc() {
1616                 $handler = $this->getHandler();
1617                 if ( $handler ) {
1618                         return $handler->getLongDesc( $this );
1619                 } else {
1620                         return MediaHandler::getGeneralLongDesc( $this );
1621                 }
1622         }
1623
1624         /**
1625          * @return string
1626          */
1627         function getShortDesc() {
1628                 $handler = $this->getHandler();
1629                 if ( $handler ) {
1630                         return $handler->getShortDesc( $this );
1631                 } else {
1632                         return MediaHandler::getGeneralShortDesc( $this );
1633                 }
1634         }
1635
1636         /**
1637          * @return string
1638          */
1639         function getDimensionsString() {
1640                 $handler = $this->getHandler();
1641                 if ( $handler ) {
1642                         return $handler->getDimensionsString( $this );
1643                 } else {
1644                         return '';
1645                 }
1646         }
1647
1648         /**
1649          * @return
1650          */
1651         function getRedirected() {
1652                 return $this->redirected;
1653         }
1654
1655         /**
1656          * @return Title
1657          */
1658         function getRedirectedTitle() {
1659                 if ( $this->redirected ) {
1660                         if ( !$this->redirectTitle ) {
1661                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1662                         }
1663                         return $this->redirectTitle;
1664                 }
1665         }
1666
1667         /**
1668          * @param  $from
1669          * @return void
1670          */
1671         function redirectedFrom( $from ) {
1672                 $this->redirected = $from;
1673         }
1674
1675         /**
1676          * @return bool
1677          */
1678         function isMissing() {
1679                 return false;
1680         }
1681
1682         /**
1683          * Assert that $this->repo is set to a valid FileRepo instance
1684          * @throws MWException
1685          */
1686         protected function assertRepoDefined() {
1687                 if ( !( $this->repo instanceof $this->repoClass ) ) {
1688                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
1689                 }
1690         }
1691
1692         /**
1693          * Assert that $this->title is set to a Title
1694          * @throws MWException
1695          */
1696         protected function assertTitleDefined() {
1697                 if ( !( $this->title instanceof Title ) ) {
1698                         throw new MWException( "A Title object is not set for this File.\n" );
1699                 }
1700         }
1701 }