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
 782                 $tmpFile = TempFSFile::factory( 'transform_', $this->getExtension() );
 783                 if ( !$tmpFile ) {
 784                         return new MediaTransformError( 'thumbnail_error',
 785                                 $params['width'], 0, wfMsg( 'thumbnail-temp-create' ) );
 786                 }
 787                 $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
 788
 789                 // Actually render the thumbnail
 790                 $thumb = $this->handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 791                 $tmpFile->bind( $thumb ); // keep alive with $thumb
 792
 793                 // Ignore errors if requested
 794                 if ( !$thumb ) {
 795                         $thumb = null;
 796                 } elseif ( $thumb->isError() ) {
 797                         $this->lastError = $thumb->toText();
 798                         if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 799                                 $thumb = $this->handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 800                         }
 801                 } elseif ( $thumb->hasFile() && !$thumb->fileIsSource() ) {
 802                         // @TODO: use a FileRepo store function
 803                         $op = array( 'op' => 'store',
 804                                 'src' => $tmpThumbPath, 'dst' => $thumbPath, 'overwriteDest' => true );
 805                         // Copy any thumbnail from the FS into storage at $dstpath
 806                         $opts = array( 'ignoreErrors' => true, 'nonLocking' => true ); // performance
 807                         if ( !$this->getRepo()->getBackend()->doOperation( $op, $opts )->isOK() ) {
 808                                 return new MediaTransformError( 'thumbnail_error',
 809                                         $params['width'], 0, wfMsg( 'thumbnail-dest-create' ) );
 810                         }
 811                 }
 812
 813                 return $thumb;
 814         }
 815
 816         /**
 817          * Transform a media file
 818          *
 819          * @param $params Array: an associative array of handler-specific parameters.
 820          *                Typical keys are width, height and page.
 821          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 822          * @return MediaTransformOutput | false
 823          */
 824         function transform( $params, $flags = 0 ) {
 825                 global $wgUseSquid;
 826
 827                 wfProfileIn( __METHOD__ );
 828                 do {
 829                         if ( !$this->canRender() ) {
 830                                 // not a bitmap or renderable image, don't try.
 831                                 $thumb = $this->iconThumb();
 832                                 break;
 833                         }
 834
 835                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 836                         $descriptionUrl =  $this->getDescriptionUrl();
 837                         if ( $descriptionUrl ) {
 838                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
 839                         }
 840
 841                         $script = $this->getTransformScript();
 842                         if ( $script && !($flags & self::RENDER_NOW) ) {
 843                                 // Use a script to transform on client request, if possible
 844                                 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
 845                                 if( $thumb ) {
 846                                         break;
 847                                 }
 848                         }
 849
 850                         $normalisedParams = $params;
 851                         $this->handler->normaliseParams( $this, $normalisedParams );
 852                         $thumbName = $this->thumbName( $normalisedParams );
 853                         $thumbUrl = $this->getThumbUrl( $thumbName );
 854
 855                         $thumb = $this->maybeDoTransform( $thumbName, $thumbUrl, $params, $flags );
 856
 857                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 858                         // purge collisions from elsewhere during failure. Don't keep triggering for
 859                         // "thumbs" which have the main image URL though (bug 13776)
 860                         if ( $wgUseSquid ) {
 861                                 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
 862                                         SquidUpdate::purge( array( $thumbUrl ) );
 863                                 }
 864                         }
 865                 } while (false);
 866
 867                 wfProfileOut( __METHOD__ );
 868                 return is_object( $thumb ) ? $thumb : false;
 869         }
 870
 871         /**
 872          * Hook into transform() to allow migration of thumbnail files
 873          * STUB
 874          * Overridden by LocalFile
 875          */
 876         function migrateThumbFile( $thumbName ) {}
 877
 878         /**
 879          * Get a MediaHandler instance for this file
 880          *
 881          * @return MediaHandler
 882          */
 883         function getHandler() {
 884                 if ( !isset( $this->handler ) ) {
 885                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
 886                 }
 887                 return $this->handler;
 888         }
 889
 890         /**
 891          * Get a ThumbnailImage representing a file type icon
 892          *
 893          * @return ThumbnailImage
 894          */
 895         function iconThumb() {
 896                 global $wgStylePath, $wgStyleDirectory;
 897
 898                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
 899                 foreach ( $try as $icon ) {
 900                         $path = '/common/images/icons/' . $icon;
 901                         $filepath = $wgStyleDirectory . $path;
 902                         if ( file_exists( $filepath ) ) { // always FS
 903                                 return new ThumbnailImage( $this, $wgStylePath . $path, 120, 120 );
 904                         }
 905                 }
 906                 return null;
 907         }
 908
 909         /**
 910          * Get last thumbnailing error.
 911          * Largely obsolete.
 912          */
 913         function getLastError() {
 914                 return $this->lastError;
 915         }
 916
 917         /**
 918          * Get all thumbnail names previously generated for this file
 919          * STUB
 920          * Overridden by LocalFile
 921          */
 922         function getThumbnails() {
 923                 return array();
 924         }
 925
 926         /**
 927          * Purge shared caches such as thumbnails and DB data caching
 928          * STUB
 929          * Overridden by LocalFile
 930          * @param $options Array Options, which include:
 931          *     'forThumbRefresh' : The purging is only to refresh thumbnails
 932          */
 933         function purgeCache( $options = array() ) {}
 934
 935         /**
 936          * Purge the file description page, but don't go after
 937          * pages using the file. Use when modifying file history
 938          * but not the current data.
 939          */
 940         function purgeDescription() {
 941                 $title = $this->getTitle();
 942                 if ( $title ) {
 943                         $title->invalidateCache();
 944                         $title->purgeSquid();
 945                 }
 946         }
 947
 948         /**
 949          * Purge metadata and all affected pages when the file is created,
 950          * deleted, or majorly updated.
 951          */
 952         function purgeEverything() {
 953                 // Delete thumbnails and refresh file metadata cache
 954                 $this->purgeCache();
 955                 $this->purgeDescription();
 956
 957                 // Purge cache of all pages using this file
 958                 $title = $this->getTitle();
 959                 if ( $title ) {
 960                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
 961                         $update->doUpdate();
 962                 }
 963         }
 964
 965         /**
 966          * Return a fragment of the history of file.
 967          *
 968          * STUB
 969          * @param $limit integer Limit of rows to return
 970          * @param $start timestamp Only revisions older than $start will be returned
 971          * @param $end timestamp Only revisions newer than $end will be returned
 972          * @param $inc bool Include the endpoints of the time range
 973          *
 974          * @return array
 975          */
 976         function getHistory($limit = null, $start = null, $end = null, $inc=true) {
 977                 return array();
 978         }
 979
 980         /**
 981          * Return the history of this file, line by line. Starts with current version,
 982          * then old versions. Should return an object similar to an image/oldimage
 983          * database row.
 984          *
 985          * STUB
 986          * Overridden in LocalFile
 987          */
 988         public function nextHistoryLine() {
 989                 return false;
 990         }
 991
 992         /**
 993          * Reset the history pointer to the first element of the history.
 994          * Always call this function after using nextHistoryLine() to free db resources
 995          * STUB
 996          * Overridden in LocalFile.
 997          */
 998         public function resetHistory() {}
 999
1000         /**
1001          * Get the filename hash component of the directory including trailing slash,
1002          * e.g. f/fa/
1003          * If the repository is not hashed, returns an empty string.
1004          *
1005          * @return string
1006          */
1007         function getHashPath() {
1008                 if ( !isset( $this->hashPath ) ) {
1009                         $this->assertRepoDefined();
1010                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1011                 }
1012                 return $this->hashPath;
1013         }
1014
1015         /**
1016          * Get the path of the file relative to the public zone root
1017          *
1018          * @return string
1019          */
1020         function getRel() {
1021                 return $this->getHashPath() . $this->getName();
1022         }
1023
1024         /**
1025          * Get urlencoded relative path of the file
1026          *
1027          * @return string
1028          */
1029         function getUrlRel() {
1030                 return $this->getHashPath() . rawurlencode( $this->getName() );
1031         }
1032
1033         /**
1034          * Get the relative path for an archived file
1035          *
1036          * @param $suffix bool|string if not false, the name of an archived thumbnail file
1037          *
1038          * @return string
1039          */
1040         function getArchiveRel( $suffix = false ) {
1041                 $path = 'archive/' . $this->getHashPath();
1042                 if ( $suffix === false ) {
1043                         $path = substr( $path, 0, -1 );
1044                 } else {
1045                         $path .= $suffix;
1046                 }
1047                 return $path;
1048         }
1049
1050         /**
1051          * Get the relative path for an archived file's thumbs directory
1052          * or a specific thumb if the $suffix is given.
1053          *
1054          * @param $archiveName string the timestamped name of an archived image
1055          * @param $suffix bool|string if not false, the name of a thumbnail file
1056          *
1057          * @return string
1058          */
1059         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1060                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1061                 if ( $suffix === false ) {
1062                         $path = substr( $path, 0, -1 );
1063                 } else {
1064                         $path .= $suffix;
1065                 }
1066                 return $path;
1067         }
1068
1069         /**
1070          * Get the path of the archived file.
1071          *
1072          * @param $suffix bool|string if not false, the name of an archived file.
1073          *
1074          * @return string
1075          */
1076         function getArchivePath( $suffix = false ) {
1077                 $this->assertRepoDefined();
1078                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1079         }
1080
1081         /**
1082          * Get the path of the archived file's thumbs, or a particular thumb if $suffix is specified
1083          *
1084          * @param $archiveName string the timestamped name of an archived image
1085          * @param $suffix bool|string if not false, the name of a thumbnail file
1086          *
1087          * @return string
1088          */
1089         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1090                 $this->assertRepoDefined();
1091                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1092                         $this->getArchiveThumbRel( $archiveName, $suffix );
1093         }
1094
1095         /**
1096          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1097          *
1098          * @param $suffix bool|string if not false, the name of a thumbnail file
1099          *
1100          * @return string
1101          */
1102         function getThumbPath( $suffix = false ) {
1103                 $this->assertRepoDefined();
1104                 $path = $this->repo->getZonePath( 'thumb' ) . '/' . $this->getRel();
1105                 if ( $suffix !== false ) {
1106                         $path .= '/' . $suffix;
1107                 }
1108                 return $path;
1109         }
1110
1111         /**
1112          * Get the URL of the archive directory, or a particular file if $suffix is specified
1113          *
1114          * @param $suffix bool|string if not false, the name of an archived file
1115          *
1116          * @return string
1117          */
1118         function getArchiveUrl( $suffix = false ) {
1119                 $this->assertRepoDefined();
1120                 $path = $this->repo->getZoneUrl( 'public' ) . '/archive/' . $this->getHashPath();
1121                 if ( $suffix === false ) {
1122                         $path = substr( $path, 0, -1 );
1123                 } else {
1124                         $path .= rawurlencode( $suffix );
1125                 }
1126                 return $path;
1127         }
1128
1129         /**
1130          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1131          *
1132          * @param $archiveName string the timestamped name of an archived image
1133          * @param $suffix bool|string if not false, the name of a thumbnail file
1134          *
1135          * @return string
1136          */
1137         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1138                 $this->assertRepoDefined();
1139                 $path = $this->repo->getZoneUrl( 'thumb' ) . '/archive/' .
1140                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1141                 if ( $suffix === false ) {
1142                         $path = substr( $path, 0, -1 );
1143                 } else {
1144                         $path .= rawurlencode( $suffix );
1145                 }
1146                 return $path;
1147         }
1148
1149         /**
1150          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1151          *
1152          * @param $suffix bool|string if not false, the name of a thumbnail file
1153          *
1154          * @return path
1155          */
1156         function getThumbUrl( $suffix = false ) {
1157                 $this->assertRepoDefined();
1158                 $path = $this->repo->getZoneUrl( 'thumb' ) . '/' . $this->getUrlRel();
1159                 if ( $suffix !== false ) {
1160                         $path .= '/' . rawurlencode( $suffix );
1161                 }
1162                 return $path;
1163         }
1164
1165         /**
1166          * Get the public zone virtual URL for a current version source file
1167          *
1168          * @param $suffix bool|string if not false, the name of a thumbnail file
1169          *
1170          * @return string
1171          */
1172         function getVirtualUrl( $suffix = false ) {
1173                 $this->assertRepoDefined();
1174                 $path = $this->repo->getVirtualUrl() . '/public/' . $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 an archived 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 getArchiveVirtualUrl( $suffix = false ) {
1189                 $this->assertRepoDefined();
1190                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1191                 if ( $suffix === false ) {
1192                         $path = substr( $path, 0, -1 );
1193                 } else {
1194                         $path .= rawurlencode( $suffix );
1195                 }
1196                 return $path;
1197         }
1198
1199         /**
1200          * Get the virtual URL for a thumbnail file or directory
1201          *
1202          * @param $suffix bool|string if not false, the name of a thumbnail file
1203          *
1204          * @return string
1205          */
1206         function getThumbVirtualUrl( $suffix = false ) {
1207                 $this->assertRepoDefined();
1208                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1209                 if ( $suffix !== false ) {
1210                         $path .= '/' . rawurlencode( $suffix );
1211                 }
1212                 return $path;
1213         }
1214
1215         /**
1216          * @return bool
1217          */
1218         function isHashed() {
1219                 $this->assertRepoDefined();
1220                 return $this->repo->isHashed();
1221         }
1222
1223         /**
1224          * @throws MWException
1225          */
1226         function readOnlyError() {
1227                 throw new MWException( get_class($this) . ': write operations are not supported' );
1228         }
1229
1230         /**
1231          * Record a file upload in the upload log and the image table
1232          * STUB
1233          * Overridden by LocalFile
1234          * @param $oldver
1235          * @param $desc
1236          * @param $license string
1237          * @param $copyStatus string
1238          * @param $source string
1239          * @param $watch bool
1240          */
1241         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
1242                 $this->readOnlyError();
1243         }
1244
1245         /**
1246          * Move or copy a file to its public location. If a file exists at the
1247          * destination, move it to an archive. Returns a FileRepoStatus object with
1248          * the archive name in the "value" member on success.
1249          *
1250          * The archive name should be passed through to recordUpload for database
1251          * registration.
1252          *
1253          * @param $srcPath String: local filesystem path to the source image
1254          * @param $flags Integer: a bitwise combination of:
1255          *     File::DELETE_SOURCE    Delete the source file, i.e. move
1256          *         rather than copy
1257          * @return FileRepoStatus object. On success, the value member contains the
1258          *     archive name, or an empty string if it was a new file.
1259          *
1260          * STUB
1261          * Overridden by LocalFile
1262          */
1263         function publish( $srcPath, $flags = 0 ) {
1264                 $this->readOnlyError();
1265         }
1266
1267         /**
1268          * @return bool
1269          */
1270         function formatMetadata() {
1271                 if ( !$this->getHandler() ) {
1272                         return false;
1273                 }
1274                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1275         }
1276
1277         /**
1278          * Returns true if the file comes from the local file repository.
1279          *
1280          * @return bool
1281          */
1282         function isLocal() {
1283                 $repo = $this->getRepo();
1284                 return $repo && $repo->isLocal();
1285         }
1286
1287         /**
1288          * Returns the name of the repository.
1289          *
1290          * @return string
1291          */
1292         function getRepoName() {
1293                 return $this->repo ? $this->repo->getName() : 'unknown';
1294         }
1295
1296         /**
1297          * Returns the repository
1298          *
1299          * @return FileRepo|false
1300          */
1301         function getRepo() {
1302                 return $this->repo;
1303         }
1304
1305         /**
1306          * Returns true if the image is an old version
1307          * STUB
1308          *
1309          * @return bool
1310          */
1311         function isOld() {
1312                 return false;
1313         }
1314
1315         /**
1316          * Is this file a "deleted" file in a private archive?
1317          * STUB
1318          *
1319          * @param $field
1320          *
1321          * @return bool
1322          */
1323         function isDeleted( $field ) {
1324                 return false;
1325         }
1326
1327         /**
1328          * Return the deletion bitfield
1329          * STUB
1330          */
1331         function getVisibility() {
1332                 return 0;
1333         }
1334
1335         /**
1336          * Was this file ever deleted from the wiki?
1337          *
1338          * @return bool
1339          */
1340         function wasDeleted() {
1341                 $title = $this->getTitle();
1342                 return $title && $title->isDeletedQuick();
1343         }
1344
1345         /**
1346          * Move file to the new title
1347          *
1348          * Move current, old version and all thumbnails
1349          * to the new filename. Old file is deleted.
1350          *
1351          * Cache purging is done; checks for validity
1352          * and logging are caller's responsibility
1353          *
1354          * @param $target Title New file name
1355          * @return FileRepoStatus object.
1356          */
1357          function move( $target ) {
1358                 $this->readOnlyError();
1359          }
1360
1361         /**
1362          * Delete all versions of the file.
1363          *
1364          * Moves the files into an archive directory (or deletes them)
1365          * and removes the database rows.
1366          *
1367          * Cache purging is done; logging is caller's responsibility.
1368          *
1369          * @param $reason String
1370          * @param $suppress Boolean: hide content from sysops?
1371          * @return true on success, false on some kind of failure
1372          * STUB
1373          * Overridden by LocalFile
1374          */
1375         function delete( $reason, $suppress = false ) {
1376                 $this->readOnlyError();
1377         }
1378
1379         /**
1380          * Restore all or specified deleted revisions to the given file.
1381          * Permissions and logging are left to the caller.
1382          *
1383          * May throw database exceptions on error.
1384          *
1385          * @param $versions array set of record ids of deleted items to restore,
1386          *                    or empty to restore all revisions.
1387          * @param $unsuppress bool remove restrictions on content upon restoration?
1388          * @return int|false the number of file revisions restored if successful,
1389          *         or false on failure
1390          * STUB
1391          * Overridden by LocalFile
1392          */
1393         function restore( $versions = array(), $unsuppress = false ) {
1394                 $this->readOnlyError();
1395         }
1396
1397         /**
1398          * Returns 'true' if this file is a type which supports multiple pages,
1399          * e.g. DJVU or PDF. Note that this may be true even if the file in
1400          * question only has a single page.
1401          *
1402          * @return Bool
1403          */
1404         function isMultipage() {
1405                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1406         }
1407
1408         /**
1409          * Returns the number of pages of a multipage document, or false for
1410          * documents which aren't multipage documents
1411          *
1412          * @return false|int
1413          */
1414         function pageCount() {
1415                 if ( !isset( $this->pageCount ) ) {
1416                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1417                                 $this->pageCount = $this->handler->pageCount( $this );
1418                         } else {
1419                                 $this->pageCount = false;
1420                         }
1421                 }
1422                 return $this->pageCount;
1423         }
1424
1425         /**
1426          * Calculate the height of a thumbnail using the source and destination width
1427          *
1428          * @param $srcWidth
1429          * @param $srcHeight
1430          * @param $dstWidth
1431          *
1432          * @return int
1433          */
1434         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1435                 // Exact integer multiply followed by division
1436                 if ( $srcWidth == 0 ) {
1437                         return 0;
1438                 } else {
1439                         return round( $srcHeight * $dstWidth / $srcWidth );
1440                 }
1441         }
1442
1443         /**
1444          * Get an image size array like that returned by getImageSize(), or false if it
1445          * can't be determined.
1446          *
1447          * @param $fileName String: The filename
1448          * @return Array
1449          */
1450         function getImageSize( $fileName ) {
1451                 if ( !$this->getHandler() ) {
1452                         return false;
1453                 }
1454                 return $this->handler->getImageSize( $this, $fileName );
1455         }
1456
1457         /**
1458          * Get the URL of the image description page. May return false if it is
1459          * unknown or not applicable.
1460          *
1461          * @return string
1462          */
1463         function getDescriptionUrl() {
1464                 if ( $this->repo ) {
1465                         return $this->repo->getDescriptionUrl( $this->getName() );
1466                 } else {
1467                         return false;
1468                 }
1469         }
1470
1471         /**
1472          * Get the HTML text of the description page, if available
1473          *
1474          * @return string
1475          */
1476         function getDescriptionText() {
1477                 global $wgMemc, $wgLang;
1478                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1479                         return false;
1480                 }
1481                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1482                 if ( $renderUrl ) {
1483                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1484                                 wfDebug("Attempting to get the description from cache...");
1485                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1486                                                                         $this->getName() );
1487                                 $obj = $wgMemc->get($key);
1488                                 if ($obj) {
1489                                         wfDebug("success!\n");
1490                                         return $obj;
1491                                 }
1492                                 wfDebug("miss\n");
1493                         }
1494                         wfDebug( "Fetching shared description from $renderUrl\n" );
1495                         $res = Http::get( $renderUrl );
1496                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1497                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1498                         }
1499                         return $res;
1500                 } else {
1501                         return false;
1502                 }
1503         }
1504
1505         /**
1506          * Get discription of file revision
1507          * STUB
1508          *
1509          * @return string
1510          */
1511         function getDescription() {
1512                 return null;
1513         }
1514
1515         /**
1516          * Get the 14-character timestamp of the file upload
1517          *
1518          * @return string|false TS_MW timestamp or false on failure
1519          */
1520         function getTimestamp() {
1521                 $this->assertRepoDefined();
1522                 return $this->repo->getFileTimestamp( $this->getPath() );
1523         }
1524
1525         /**
1526          * Get the SHA-1 base 36 hash of the file
1527          *
1528          * @return string
1529          */
1530         function getSha1() {
1531                 $this->assertRepoDefined();
1532                 return $this->repo->getFileSha1( $this->getPath() );
1533         }
1534
1535         /**
1536          * Get the deletion archive key, <sha1>.<ext>
1537          *
1538          * @return string
1539          */
1540         function getStorageKey() {
1541                 $hash = $this->getSha1();
1542                 if ( !$hash ) {
1543                         return false;
1544                 }
1545                 $ext = $this->getExtension();
1546                 $dotExt = $ext === '' ? '' : ".$ext";
1547                 return $hash . $dotExt;
1548         }
1549
1550         /**
1551          * Determine if the current user is allowed to view a particular
1552          * field of this file, if it's marked as deleted.
1553          * STUB
1554          * @param $field Integer
1555          * @param $user User object to check, or null to use $wgUser
1556          * @return Boolean
1557          */
1558         function userCan( $field, User $user = null ) {
1559                 return true;
1560         }
1561
1562         /**
1563          * Get an associative array containing information about a file in the local filesystem.
1564          *
1565          * @param $path String: absolute local filesystem path
1566          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1567          *             Set it to false to ignore the extension.
1568          *
1569          * @return array
1570          */
1571         static function getPropsFromPath( $path, $ext = true ) {
1572                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1573                 wfDeprecated( __METHOD__, '1.19' );
1574
1575                 $fsFile = new FSFile( $path );
1576                 return $fsFile->getProps();
1577         }
1578
1579         /**
1580          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1581          * encoding, zero padded to 31 digits.
1582          *
1583          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1584          * fairly neatly.
1585          *
1586          * @param $path string
1587          *
1588          * @return false|string False on failure
1589          */
1590         static function sha1Base36( $path ) {
1591                 wfDeprecated( __METHOD__, '1.19' );
1592
1593                 $fsFile = new FSFile( $path );
1594                 return $fsFile->getSha1Base36();
1595         }
1596
1597         /**
1598          * @return string
1599          */
1600         function getLongDesc() {
1601                 $handler = $this->getHandler();
1602                 if ( $handler ) {
1603                         return $handler->getLongDesc( $this );
1604                 } else {
1605                         return MediaHandler::getGeneralLongDesc( $this );
1606                 }
1607         }
1608
1609         /**
1610          * @return string
1611          */
1612         function getShortDesc() {
1613                 $handler = $this->getHandler();
1614                 if ( $handler ) {
1615                         return $handler->getShortDesc( $this );
1616                 } else {
1617                         return MediaHandler::getGeneralShortDesc( $this );
1618                 }
1619         }
1620
1621         /**
1622          * @return string
1623          */
1624         function getDimensionsString() {
1625                 $handler = $this->getHandler();
1626                 if ( $handler ) {
1627                         return $handler->getDimensionsString( $this );
1628                 } else {
1629                         return '';
1630                 }
1631         }
1632
1633         /**
1634          * @return
1635          */
1636         function getRedirected() {
1637                 return $this->redirected;
1638         }
1639
1640         /**
1641          * @return Title
1642          */
1643         function getRedirectedTitle() {
1644                 if ( $this->redirected ) {
1645                         if ( !$this->redirectTitle ) {
1646                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1647                         }
1648                         return $this->redirectTitle;
1649                 }
1650         }
1651
1652         /**
1653          * @param  $from
1654          * @return void
1655          */
1656         function redirectedFrom( $from ) {
1657                 $this->redirected = $from;
1658         }
1659
1660         /**
1661          * @return bool
1662          */
1663         function isMissing() {
1664                 return false;
1665         }
1666
1667         /**
1668          * Assert that $this->repo is set to a valid FileRepo instance
1669          * @throws MWException
1670          */
1671         protected function assertRepoDefined() {
1672                 if ( !( $this->repo instanceof $this->repoClass ) ) {
1673                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
1674                 }
1675         }
1676
1677         /**
1678          * Assert that $this->title is set to a Title
1679          * @throws MWException
1680          */
1681         protected function assertTitleDefined() {
1682                 if ( !( $this->title instanceof Title ) ) {
1683                         throw new MWException( "A Title object is not set for this File.\n" );
1684                 }
1685         }
1686 }