includes/filerepo/file/File.php

   1 <?php
   2 /**
   3  * @defgroup FileAbstraction File abstraction
   4  * @ingroup FileRepo
   5  *
   6  * Represents files in a repository.
   7  */
   8
   9 /**
  10  * Base code for files.
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License along
  23  * with this program; if not, write to the Free Software Foundation, Inc.,
  24  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  25  * http://www.gnu.org/copyleft/gpl.html
  26  *
  27  * @file
  28  * @ingroup FileAbstraction
  29  */
  30
  31 /**
  32  * Implements some public methods and some protected utility functions which
  33  * are required by multiple child classes. Contains stub functionality for
  34  * unimplemented public methods.
  35  *
  36  * Stub functions which should be overridden are marked with STUB. Some more
  37  * concrete functions are also typically overridden by child classes.
  38  *
  39  * Note that only the repo object knows what its file class is called. You should
  40  * never name a file class explictly outside of the repo class. Instead use the
  41  * repo's factory functions to generate file objects, for example:
  42  *
  43  * RepoGroup::singleton()->getLocalRepo()->newFile($title);
  44  *
  45  * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
  46  * in most cases.
  47  *
  48  * @ingroup FileAbstraction
  49  */
  50 abstract class File {
  51         const DELETED_FILE = 1;
  52         const DELETED_COMMENT = 2;
  53         const DELETED_USER = 4;
  54         const DELETED_RESTRICTED = 8;
  55
  56         /** Force rendering in the current process */
  57         const RENDER_NOW   = 1;
  58         /**
  59          * Force rendering even if thumbnail already exist and using RENDER_NOW
  60          * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
  61          */
  62         const RENDER_FORCE = 2;
  63
  64         const DELETE_SOURCE = 1;
  65
  66         // Audience options for File::getDescription()
  67         const FOR_PUBLIC = 1;
  68         const FOR_THIS_USER = 2;
  69         const RAW = 3;
  70
  71         // Options for File::thumbName()
  72         const THUMB_FULL_NAME = 1;
  73
  74         /**
  75          * Some member variables can be lazy-initialised using __get(). The
  76          * initialisation function for these variables is always a function named
  77          * like getVar(), where Var is the variable name with upper-case first
  78          * letter.
  79          *
  80          * The following variables are initialised in this way in this base class:
  81          *    name, extension, handler, path, canRender, isSafeFile,
  82          *    transformScript, hashPath, pageCount, url
  83          *
  84          * Code within this class should generally use the accessor function
  85          * directly, since __get() isn't re-entrant and therefore causes bugs that
  86          * depend on initialisation order.
  87          */
  88
  89         /**
  90          * The following member variables are not lazy-initialised
  91          */
  92
  93         /**
  94          * @var FileRepo|bool
  95          */
  96         var $repo;
  97
  98         /**
  99          * @var Title
 100          */
 101         var $title;
 102
 103         var $lastError, $redirected, $redirectedTitle;
 104
 105         /**
 106          * @var FSFile|bool False if undefined
 107          */
 108         protected $fsFile;
 109
 110         /**
 111          * @var MediaHandler
 112          */
 113         protected $handler;
 114
 115         /**
 116          * @var string
 117          */
 118         protected $url, $extension, $name, $path, $hashPath, $pageCount, $transformScript;
 119
 120         protected $redirectTitle;
 121
 122         /**
 123          * @var bool
 124          */
 125         protected $canRender, $isSafeFile;
 126
 127         /**
 128          * @var string Required Repository class type
 129          */
 130         protected $repoClass = 'FileRepo';
 131
 132         /**
 133          * Call this constructor from child classes.
 134          *
 135          * Both $title and $repo are optional, though some functions
 136          * may return false or throw exceptions if they are not set.
 137          * Most subclasses will want to call assertRepoDefined() here.
 138          *
 139          * @param $title Title|string|bool
 140          * @param $repo FileRepo|bool
 141          */
 142         function __construct( $title, $repo ) {
 143                 if ( $title !== false ) { // subclasses may not use MW titles
 144                         $title = self::normalizeTitle( $title, 'exception' );
 145                 }
 146                 $this->title = $title;
 147                 $this->repo = $repo;
 148         }
 149
 150         /**
 151          * Given a string or Title object return either a
 152          * valid Title object with namespace NS_FILE or null
 153          *
 154          * @param $title Title|string
 155          * @param $exception string|bool Use 'exception' to throw an error on bad titles
 156          * @throws MWException
 157          * @return Title|null
 158          */
 159         static function normalizeTitle( $title, $exception = false ) {
 160                 $ret = $title;
 161                 if ( $ret instanceof Title ) {
 162                         # Normalize NS_MEDIA -> NS_FILE
 163                         if ( $ret->getNamespace() == NS_MEDIA ) {
 164                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 165                         # Sanity check the title namespace
 166                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 167                                 $ret = null;
 168                         }
 169                 } else {
 170                         # Convert strings to Title objects
 171                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 172                 }
 173                 if ( !$ret && $exception !== false ) {
 174                         throw new MWException( "`$title` is not a valid file title." );
 175                 }
 176                 return $ret;
 177         }
 178
 179         function __get( $name ) {
 180                 $function = array( $this, 'get' . ucfirst( $name ) );
 181                 if ( !is_callable( $function ) ) {
 182                         return null;
 183                 } else {
 184                         $this->$name = call_user_func( $function );
 185                         return $this->$name;
 186                 }
 187         }
 188
 189         /**
 190          * Normalize a file extension to the common form, and ensure it's clean.
 191          * Extensions with non-alphanumeric characters will be discarded.
 192          *
 193          * @param $ext string (without the .)
 194          * @return string
 195          */
 196         static function normalizeExtension( $ext ) {
 197                 $lower = strtolower( $ext );
 198                 $squish = array(
 199                         'htm' => 'html',
 200                         'jpeg' => 'jpg',
 201                         'mpeg' => 'mpg',
 202                         'tiff' => 'tif',
 203                         'ogv' => 'ogg' );
 204                 if( isset( $squish[$lower] ) ) {
 205                         return $squish[$lower];
 206                 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 207                         return $lower;
 208                 } else {
 209                         return '';
 210                 }
 211         }
 212
 213         /**
 214          * Checks if file extensions are compatible
 215          *
 216          * @param $old File Old file
 217          * @param $new string New name
 218          *
 219          * @return bool|null
 220          */
 221         static function checkExtensionCompatibility( File $old, $new ) {
 222                 $oldMime = $old->getMimeType();
 223                 $n = strrpos( $new, '.' );
 224                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 225                 $mimeMagic = MimeMagic::singleton();
 226                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 227         }
 228
 229         /**
 230          * Upgrade the database row if there is one
 231          * Called by ImagePage
 232          * STUB
 233          */
 234         function upgradeRow() {}
 235
 236         /**
 237          * Split an internet media type into its two components; if not
 238          * a two-part name, set the minor type to 'unknown'.
 239          *
 240          * @param string $mime "text/html" etc
 241          * @return array ("text", "html") etc
 242          */
 243         public static function splitMime( $mime ) {
 244                 if( strpos( $mime, '/' ) !== false ) {
 245                         return explode( '/', $mime, 2 );
 246                 } else {
 247                         return array( $mime, 'unknown' );
 248                 }
 249         }
 250
 251         /**
 252          * Callback for usort() to do file sorts by name
 253          *
 254          * @param $a File
 255          * @param $b File
 256          *
 257          * @return Integer: result of name comparison
 258          */
 259         public static function compare( File $a, File $b ) {
 260                 return strcmp( $a->getName(), $b->getName() );
 261         }
 262
 263         /**
 264          * Return the name of this file
 265          *
 266          * @return string
 267          */
 268         public function getName() {
 269                 if ( !isset( $this->name ) ) {
 270                         $this->assertRepoDefined();
 271                         $this->name = $this->repo->getNameFromTitle( $this->title );
 272                 }
 273                 return $this->name;
 274         }
 275
 276         /**
 277          * Get the file extension, e.g. "svg"
 278          *
 279          * @return string
 280          */
 281         function getExtension() {
 282                 if ( !isset( $this->extension ) ) {
 283                         $n = strrpos( $this->getName(), '.' );
 284                         $this->extension = self::normalizeExtension(
 285                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 286                 }
 287                 return $this->extension;
 288         }
 289
 290         /**
 291          * Return the associated title object
 292          *
 293          * @return Title
 294          */
 295         public function getTitle() {
 296                 return $this->title;
 297         }
 298
 299         /**
 300          * Return the title used to find this file
 301          *
 302          * @return Title
 303          */
 304         public function getOriginalTitle() {
 305                 if ( $this->redirected ) {
 306                         return $this->getRedirectedTitle();
 307                 }
 308                 return $this->title;
 309         }
 310
 311         /**
 312          * Return the URL of the file
 313          *
 314          * @return string
 315          */
 316         public function getUrl() {
 317                 if ( !isset( $this->url ) ) {
 318                         $this->assertRepoDefined();
 319                         $ext = $this->getExtension();
 320                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 321                 }
 322                 return $this->url;
 323         }
 324
 325         /**
 326          * Return a fully-qualified URL to the file.
 327          * Upload URL paths _may or may not_ be fully qualified, so
 328          * we check. Local paths are assumed to belong on $wgServer.
 329          *
 330          * @return String
 331          */
 332         public function getFullUrl() {
 333                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 334         }
 335
 336         /**
 337          * @return string
 338          */
 339         public function getCanonicalUrl() {
 340                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 341         }
 342
 343         /**
 344          * @return string
 345          */
 346         function getViewURL() {
 347                 if ( $this->mustRender() ) {
 348                         if ( $this->canRender() ) {
 349                                 return $this->createThumb( $this->getWidth() );
 350                         } else {
 351                                 wfDebug( __METHOD__.': supposed to render ' . $this->getName() .
 352                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 353                                 return $this->getURL(); #hm... return NULL?
 354                         }
 355                 } else {
 356                         return $this->getURL();
 357                 }
 358         }
 359
 360         /**
 361          * Return the storage path to the file. Note that this does
 362          * not mean that a file actually exists under that location.
 363          *
 364          * This path depends on whether directory hashing is active or not,
 365          * i.e. whether the files are all found in the same directory,
 366          * or in hashed paths like /images/3/3c.
 367          *
 368          * Most callers don't check the return value, but ForeignAPIFile::getPath
 369          * returns false.
 370          *
 371          * @return string|bool ForeignAPIFile::getPath can return false
 372         */
 373         public function getPath() {
 374                 if ( !isset( $this->path ) ) {
 375                         $this->assertRepoDefined();
 376                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 377                 }
 378                 return $this->path;
 379         }
 380
 381         /**
 382          * Get an FS copy or original of this file and return the path.
 383          * Returns false on failure. Callers must not alter the file.
 384          * Temporary files are cleared automatically.
 385          *
 386          * @return string|bool False on failure
 387          */
 388         public function getLocalRefPath() {
 389                 $this->assertRepoDefined();
 390                 if ( !isset( $this->fsFile ) ) {
 391                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 392                         if ( !$this->fsFile ) {
 393                                 $this->fsFile = false; // null => false; cache negative hits
 394                         }
 395                 }
 396                 return ( $this->fsFile )
 397                         ? $this->fsFile->getPath()
 398                         : false;
 399         }
 400
 401         /**
 402          * Return the width of the image. Returns false if the width is unknown
 403          * or undefined.
 404          *
 405          * STUB
 406          * Overridden by LocalFile, UnregisteredLocalFile
 407          *
 408          * @param $page int
 409          *
 410          * @return number
 411          */
 412         public function getWidth( $page = 1 ) {
 413                 return false;
 414         }
 415
 416         /**
 417          * Return the height of the image. Returns false if the height is unknown
 418          * or undefined
 419          *
 420          * STUB
 421          * Overridden by LocalFile, UnregisteredLocalFile
 422          *
 423          * @param $page int
 424          *
 425          * @return bool|number False on failure
 426          */
 427         public function getHeight( $page = 1 ) {
 428                 return false;
 429         }
 430
 431         /**
 432          * Returns ID or name of user who uploaded the file
 433          * STUB
 434          *
 435          * @param $type string 'text' or 'id'
 436          *
 437          * @return string|int
 438          */
 439         public function getUser( $type = 'text' ) {
 440                 return null;
 441         }
 442
 443         /**
 444          * Get the duration of a media file in seconds
 445          *
 446          * @return number
 447          */
 448         public function getLength() {
 449                 $handler = $this->getHandler();
 450                 if ( $handler ) {
 451                         return $handler->getLength( $this );
 452                 } else {
 453                         return 0;
 454                 }
 455         }
 456
 457         /**
 458          * Return true if the file is vectorized
 459          *
 460          * @return bool
 461          */
 462         public function isVectorized() {
 463                 $handler = $this->getHandler();
 464                 if ( $handler ) {
 465                         return $handler->isVectorized( $this );
 466                 } else {
 467                         return false;
 468                 }
 469         }
 470
 471         /**
 472          * Will the thumbnail be animated if one would expect it to be.
 473          *
 474          * Currently used to add a warning to the image description page
 475          *
 476          * @return bool false if the main image is both animated
 477          *   and the thumbnail is not. In all other cases must return
 478          *   true. If image is not renderable whatsoever, should
 479          *   return true.
 480          */
 481         public function canAnimateThumbIfAppropriate() {
 482                 $handler = $this->getHandler();
 483                 if ( !$handler ) {
 484                         // We cannot handle image whatsoever, thus
 485                         // one would not expect it to be animated
 486                         // so true.
 487                         return true;
 488                 } else {
 489                         if ( $this->allowInlineDisplay()
 490                                 && $handler->isAnimatedImage( $this )
 491                                 && !$handler->canAnimateThumbnail( $this )
 492                         ) {
 493                                 // Image is animated, but thumbnail isn't.
 494                                 // This is unexpected to the user.
 495                                 return false;
 496                         } else {
 497                                 // Image is not animated, so one would
 498                                 // not expect thumb to be
 499                                 return true;
 500                         }
 501                 }
 502         }
 503
 504         /**
 505          * Get handler-specific metadata
 506          * Overridden by LocalFile, UnregisteredLocalFile
 507          * STUB
 508          * @return bool
 509          */
 510         public function getMetadata() {
 511                 return false;
 512         }
 513
 514         /**
 515         * get versioned metadata
 516         *
 517         * @param $metadata Mixed Array or String of (serialized) metadata
 518         * @param $version integer version number.
 519         * @return Array containing metadata, or what was passed to it on fail (unserializing if not array)
 520         */
 521         public function convertMetadataVersion($metadata, $version) {
 522                 $handler = $this->getHandler();
 523                 if ( !is_array( $metadata ) ) {
 524                         // Just to make the return type consistent
 525                         $metadata = unserialize( $metadata );
 526                 }
 527                 if ( $handler ) {
 528                         return $handler->convertMetadataVersion( $metadata, $version );
 529                 } else {
 530                         return $metadata;
 531                 }
 532         }
 533
 534         /**
 535          * Return the bit depth of the file
 536          * Overridden by LocalFile
 537          * STUB
 538          * @return int
 539          */
 540         public function getBitDepth() {
 541                 return 0;
 542         }
 543
 544         /**
 545          * Return the size of the image file, in bytes
 546          * Overridden by LocalFile, UnregisteredLocalFile
 547          * STUB
 548          * @return bool
 549          */
 550         public function getSize() {
 551                 return false;
 552         }
 553
 554         /**
 555          * Returns the mime type of the file.
 556          * Overridden by LocalFile, UnregisteredLocalFile
 557          * STUB
 558          *
 559          * @return string
 560          */
 561         function getMimeType() {
 562                 return 'unknown/unknown';
 563         }
 564
 565         /**
 566          * Return the type of the media in the file.
 567          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 568          * Overridden by LocalFile,
 569          * STUB
 570          * @return string
 571          */
 572         function getMediaType() {
 573                 return MEDIATYPE_UNKNOWN;
 574         }
 575
 576         /**
 577          * Checks if the output of transform() for this file is likely
 578          * to be valid. If this is false, various user elements will
 579          * display a placeholder instead.
 580          *
 581          * Currently, this checks if the file is an image format
 582          * that can be converted to a format
 583          * supported by all browsers (namely GIF, PNG and JPEG),
 584          * or if it is an SVG image and SVG conversion is enabled.
 585          *
 586          * @return bool
 587          */
 588         function canRender() {
 589                 if ( !isset( $this->canRender ) ) {
 590                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 591                 }
 592                 return $this->canRender;
 593         }
 594
 595         /**
 596          * Accessor for __get()
 597          * @return bool
 598          */
 599         protected function getCanRender() {
 600                 return $this->canRender();
 601         }
 602
 603         /**
 604          * Return true if the file is of a type that can't be directly
 605          * rendered by typical browsers and needs to be re-rasterized.
 606          *
 607          * This returns true for everything but the bitmap types
 608          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 609          * also return true for any non-image formats.
 610          *
 611          * @return bool
 612          */
 613         function mustRender() {
 614                 return $this->getHandler() && $this->handler->mustRender( $this );
 615         }
 616
 617         /**
 618          * Alias for canRender()
 619          *
 620          * @return bool
 621          */
 622         function allowInlineDisplay() {
 623                 return $this->canRender();
 624         }
 625
 626         /**
 627          * Determines if this media file is in a format that is unlikely to
 628          * contain viruses or malicious content. It uses the global
 629          * $wgTrustedMediaFormats list to determine if the file is safe.
 630          *
 631          * This is used to show a warning on the description page of non-safe files.
 632          * It may also be used to disallow direct [[media:...]] links to such files.
 633          *
 634          * Note that this function will always return true if allowInlineDisplay()
 635          * or isTrustedFile() is true for this file.
 636          *
 637          * @return bool
 638          */
 639         function isSafeFile() {
 640                 if ( !isset( $this->isSafeFile ) ) {
 641                         $this->isSafeFile = $this->_getIsSafeFile();
 642                 }
 643                 return $this->isSafeFile;
 644         }
 645
 646         /**
 647          * Accessor for __get()
 648          *
 649          * @return bool
 650          */
 651         protected function getIsSafeFile() {
 652                 return $this->isSafeFile();
 653         }
 654
 655         /**
 656          * Uncached accessor
 657          *
 658          * @return bool
 659          */
 660         protected function _getIsSafeFile() {
 661                 global $wgTrustedMediaFormats;
 662
 663                 if ( $this->allowInlineDisplay() ) {
 664                         return true;
 665                 }
 666                 if ($this->isTrustedFile()) {
 667                         return true;
 668                 }
 669
 670                 $type = $this->getMediaType();
 671                 $mime = $this->getMimeType();
 672                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 673
 674                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 675                         return false; #unknown type, not trusted
 676                 }
 677                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 678                         return true;
 679                 }
 680
 681                 if ( $mime === "unknown/unknown" ) {
 682                         return false; #unknown type, not trusted
 683                 }
 684                 if ( in_array( $mime, $wgTrustedMediaFormats) ) {
 685                         return true;
 686                 }
 687
 688                 return false;
 689         }
 690
 691         /**
 692          * Returns true if the file is flagged as trusted. Files flagged that way
 693          * can be linked to directly, even if that is not allowed for this type of
 694          * file normally.
 695          *
 696          * This is a dummy function right now and always returns false. It could be
 697          * implemented to extract a flag from the database. The trusted flag could be
 698          * set on upload, if the user has sufficient privileges, to bypass script-
 699          * and html-filters. It may even be coupled with cryptographics signatures
 700          * or such.
 701          *
 702          * @return bool
 703          */
 704         function isTrustedFile() {
 705                 #this could be implemented to check a flag in the database,
 706                 #look for signatures, etc
 707                 return false;
 708         }
 709
 710         /**
 711          * Returns true if file exists in the repository.
 712          *
 713          * Overridden by LocalFile to avoid unnecessary stat calls.
 714          *
 715          * @return boolean Whether file exists in the repository.
 716          */
 717         public function exists() {
 718                 return $this->getPath() && $this->repo->fileExists( $this->path );
 719         }
 720
 721         /**
 722          * Returns true if file exists in the repository and can be included in a page.
 723          * It would be unsafe to include private images, making public thumbnails inadvertently
 724          *
 725          * @return boolean Whether file exists in the repository and is includable.
 726          */
 727         public function isVisible() {
 728                 return $this->exists();
 729         }
 730
 731         /**
 732          * @return string
 733          */
 734         function getTransformScript() {
 735                 if ( !isset( $this->transformScript ) ) {
 736                         $this->transformScript = false;
 737                         if ( $this->repo ) {
 738                                 $script = $this->repo->getThumbScriptUrl();
 739                                 if ( $script ) {
 740                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 741                                 }
 742                         }
 743                 }
 744                 return $this->transformScript;
 745         }
 746
 747         /**
 748          * Get a ThumbnailImage which is the same size as the source
 749          *
 750          * @param $handlerParams array
 751          *
 752          * @return string
 753          */
 754         function getUnscaledThumb( $handlerParams = array() ) {
 755                 $hp =& $handlerParams;
 756                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 757                 $width = $this->getWidth( $page );
 758                 if ( !$width ) {
 759                         return $this->iconThumb();
 760                 }
 761                 $hp['width'] = $width;
 762                 return $this->transform( $hp );
 763         }
 764
 765         /**
 766          * Return the file name of a thumbnail with the specified parameters.
 767          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 768          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 769          *
 770          * @param $params Array: handler-specific parameters
 771          * @param $flags integer Bitfield that supports THUMB_* constants
 772          * @return string
 773          */
 774         public function thumbName( $params, $flags = 0 ) {
 775                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 776                         ? $this->repo->nameForThumb( $this->getName() )
 777                         : $this->getName();
 778                 return $this->generateThumbName( $name, $params );
 779         }
 780
 781         /**
 782          * Generate a thumbnail file name from a name and specified parameters
 783          *
 784          * @param string $name
 785          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 786          *
 787          * @return string
 788          */
 789         public function generateThumbName( $name, $params ) {
 790                 if ( !$this->getHandler() ) {
 791                         return null;
 792                 }
 793                 $extension = $this->getExtension();
 794                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType(
 795                         $extension, $this->getMimeType(), $params );
 796                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 797                 if ( $thumbExt != $extension ) {
 798                         $thumbName .= ".$thumbExt";
 799                 }
 800                 return $thumbName;
 801         }
 802
 803         /**
 804          * Create a thumbnail of the image having the specified width/height.
 805          * The thumbnail will not be created if the width is larger than the
 806          * image's width. Let the browser do the scaling in this case.
 807          * The thumbnail is stored on disk and is only computed if the thumbnail
 808          * file does not exist OR if it is older than the image.
 809          * Returns the URL.
 810          *
 811          * Keeps aspect ratio of original image. If both width and height are
 812          * specified, the generated image will be no bigger than width x height,
 813          * and will also have correct aspect ratio.
 814          *
 815          * @param $width Integer: maximum width of the generated thumbnail
 816          * @param $height Integer: maximum height of the image (optional)
 817          *
 818          * @return string
 819          */
 820         public function createThumb( $width, $height = -1 ) {
 821                 $params = array( 'width' => $width );
 822                 if ( $height != -1 ) {
 823                         $params['height'] = $height;
 824                 }
 825                 $thumb = $this->transform( $params );
 826                 if ( is_null( $thumb ) || $thumb->isError() ) {
 827                         return '';
 828                 }
 829                 return $thumb->getUrl();
 830         }
 831
 832         /**
 833          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 834          *
 835          * @param $thumbPath string Thumbnail storage path
 836          * @param $thumbUrl string Thumbnail URL
 837          * @param $params Array
 838          * @param $flags integer
 839          * @return MediaTransformOutput
 840          */
 841         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 842                 global $wgIgnoreImageErrors;
 843
 844                 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 845                         return $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 846                 } else {
 847                         return new MediaTransformError( 'thumbnail_error',
 848                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 849                 }
 850         }
 851
 852         /**
 853          * Transform a media file
 854          *
 855          * @param $params Array: an associative array of handler-specific parameters.
 856          *                Typical keys are width, height and page.
 857          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 858          * @return MediaTransformOutput|bool False on failure
 859          */
 860         function transform( $params, $flags = 0 ) {
 861                 global $wgUseSquid, $wgIgnoreImageErrors, $wgThumbnailEpoch;
 862
 863                 wfProfileIn( __METHOD__ );
 864                 do {
 865                         if ( !$this->canRender() ) {
 866                                 $thumb = $this->iconThumb();
 867                                 break; // not a bitmap or renderable image, don't try
 868                         }
 869
 870                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 871                         $descriptionUrl = $this->getDescriptionUrl();
 872                         if ( $descriptionUrl ) {
 873                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
 874                         }
 875
 876                         $script = $this->getTransformScript();
 877                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
 878                                 // Use a script to transform on client request, if possible
 879                                 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
 880                                 if ( $thumb ) {
 881                                         break;
 882                                 }
 883                         }
 884
 885                         $normalisedParams = $params;
 886                         $this->handler->normaliseParams( $this, $normalisedParams );
 887
 888                         $thumbName = $this->thumbName( $normalisedParams );
 889                         $thumbUrl = $this->getThumbUrl( $thumbName );
 890                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
 891
 892                         if ( $this->repo ) {
 893                                 // Defer rendering if a 404 handler is set up...
 894                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
 895                                         wfDebug( __METHOD__ . " transformation deferred." );
 896                                         // XXX: Pass in the storage path even though we are not rendering anything
 897                                         // and the path is supposed to be an FS path. This is due to getScalerType()
 898                                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
 899                                         $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 900                                         break;
 901                                 }
 902                                 // Clean up broken thumbnails as needed
 903                                 $this->migrateThumbFile( $thumbName );
 904                                 // Check if an up-to-date thumbnail already exists...
 905                                 wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
 906                                 if ( $this->repo->fileExists( $thumbPath ) && !( $flags & self::RENDER_FORCE ) ) {
 907                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
 908                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
 909                                                 // XXX: Pass in the storage path even though we are not rendering anything
 910                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
 911                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
 912                                                 $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 913                                                 $thumb->setStoragePath( $thumbPath );
 914                                                 break;
 915                                         }
 916                                 } elseif ( $flags & self::RENDER_FORCE ) {
 917                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
 918                                 }
 919                         }
 920
 921                         // If the backend is ready-only, don't keep generating thumbnails
 922                         // only to return transformation errors, just return the error now.
 923                         if ( $this->repo->getReadOnlyReason() !== false ) {
 924                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 925                                 break;
 926                         }
 927
 928                         // Create a temp FS file with the same extension and the thumbnail
 929                         $thumbExt = FileBackend::extensionFromPath( $thumbPath );
 930                         $tmpFile = TempFSFile::factory( 'transform_', $thumbExt );
 931                         if ( !$tmpFile ) {
 932                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 933                                 break;
 934                         }
 935                         $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
 936
 937                         // Actually render the thumbnail...
 938                         wfProfileIn( __METHOD__ . '-doTransform' );
 939                         $thumb = $this->handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 940                         wfProfileOut( __METHOD__ . '-doTransform' );
 941                         $tmpFile->bind( $thumb ); // keep alive with $thumb
 942
 943                         if ( !$thumb ) { // bad params?
 944                                 $thumb = null;
 945                         } elseif ( $thumb->isError() ) { // transform error
 946                                 $this->lastError = $thumb->toText();
 947                                 // Ignore errors if requested
 948                                 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 949                                         $thumb = $this->handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
 950                                 }
 951                         } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
 952                                 // Copy the thumbnail from the file system into storage...
 953                                 $disposition = $this->getThumbDisposition( $thumbName );
 954                                 $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
 955                                 if ( $status->isOK() ) {
 956                                         $thumb->setStoragePath( $thumbPath );
 957                                 } else {
 958                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
 959                                 }
 960                                 // Give extensions a chance to do something with this thumbnail...
 961                                 wfRunHooks( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
 962                         }
 963
 964                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 965                         // purge collisions from elsewhere during failure. Don't keep triggering for
 966                         // "thumbs" which have the main image URL though (bug 13776)
 967                         if ( $wgUseSquid ) {
 968                                 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
 969                                         SquidUpdate::purge( array( $thumbUrl ) );
 970                                 }
 971                         }
 972                 } while ( false );
 973
 974                 wfProfileOut( __METHOD__ );
 975                 return is_object( $thumb ) ? $thumb : false;
 976         }
 977
 978         /**
 979          * @param $thumbName string Thumbnail name
 980          * @return string Content-Disposition header value
 981          */
 982         function getThumbDisposition( $thumbName ) {
 983                 $fileName = $this->name; // file name to suggest
 984                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
 985                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
 986                         $fileName .= ".$thumbExt";
 987                 }
 988                 return FileBackend::makeContentDisposition( 'inline', $fileName );
 989         }
 990
 991         /**
 992          * Hook into transform() to allow migration of thumbnail files
 993          * STUB
 994          * Overridden by LocalFile
 995          */
 996         function migrateThumbFile( $thumbName ) {}
 997
 998         /**
 999          * Get a MediaHandler instance for this file
1000          *
1001          * @return MediaHandler
1002          */
1003         function getHandler() {
1004                 if ( !isset( $this->handler ) ) {
1005                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1006                 }
1007                 return $this->handler;
1008         }
1009
1010         /**
1011          * Get a ThumbnailImage representing a file type icon
1012          *
1013          * @return ThumbnailImage
1014          */
1015         function iconThumb() {
1016                 global $wgStylePath, $wgStyleDirectory;
1017
1018                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1019                 foreach ( $try as $icon ) {
1020                         $path = '/common/images/icons/' . $icon;
1021                         $filepath = $wgStyleDirectory . $path;
1022                         if ( file_exists( $filepath ) ) { // always FS
1023                                 $params = array( 'width' => 120, 'height' => 120 );
1024                                 return new ThumbnailImage( $this, $wgStylePath . $path, false, $params );
1025                         }
1026                 }
1027                 return null;
1028         }
1029
1030         /**
1031          * Get last thumbnailing error.
1032          * Largely obsolete.
1033          */
1034         function getLastError() {
1035                 return $this->lastError;
1036         }
1037
1038         /**
1039          * Get all thumbnail names previously generated for this file
1040          * STUB
1041          * Overridden by LocalFile
1042          * @return array
1043          */
1044         function getThumbnails() {
1045                 return array();
1046         }
1047
1048         /**
1049          * Purge shared caches such as thumbnails and DB data caching
1050          * STUB
1051          * Overridden by LocalFile
1052          * @param $options Array Options, which include:
1053          *     'forThumbRefresh' : The purging is only to refresh thumbnails
1054          */
1055         function purgeCache( $options = array() ) {}
1056
1057         /**
1058          * Purge the file description page, but don't go after
1059          * pages using the file. Use when modifying file history
1060          * but not the current data.
1061          */
1062         function purgeDescription() {
1063                 $title = $this->getTitle();
1064                 if ( $title ) {
1065                         $title->invalidateCache();
1066                         $title->purgeSquid();
1067                 }
1068         }
1069
1070         /**
1071          * Purge metadata and all affected pages when the file is created,
1072          * deleted, or majorly updated.
1073          */
1074         function purgeEverything() {
1075                 // Delete thumbnails and refresh file metadata cache
1076                 $this->purgeCache();
1077                 $this->purgeDescription();
1078
1079                 // Purge cache of all pages using this file
1080                 $title = $this->getTitle();
1081                 if ( $title ) {
1082                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1083                         $update->doUpdate();
1084                 }
1085         }
1086
1087         /**
1088          * Return a fragment of the history of file.
1089          *
1090          * STUB
1091          * @param $limit integer Limit of rows to return
1092          * @param $start string timestamp Only revisions older than $start will be returned
1093          * @param $end string timestamp Only revisions newer than $end will be returned
1094          * @param $inc bool Include the endpoints of the time range
1095          *
1096          * @return array
1097          */
1098         function getHistory( $limit = null, $start = null, $end = null, $inc=true ) {
1099                 return array();
1100         }
1101
1102         /**
1103          * Return the history of this file, line by line. Starts with current version,
1104          * then old versions. Should return an object similar to an image/oldimage
1105          * database row.
1106          *
1107          * STUB
1108          * Overridden in LocalFile
1109          * @return bool
1110          */
1111         public function nextHistoryLine() {
1112                 return false;
1113         }
1114
1115         /**
1116          * Reset the history pointer to the first element of the history.
1117          * Always call this function after using nextHistoryLine() to free db resources
1118          * STUB
1119          * Overridden in LocalFile.
1120          */
1121         public function resetHistory() {}
1122
1123         /**
1124          * Get the filename hash component of the directory including trailing slash,
1125          * e.g. f/fa/
1126          * If the repository is not hashed, returns an empty string.
1127          *
1128          * @return string
1129          */
1130         function getHashPath() {
1131                 if ( !isset( $this->hashPath ) ) {
1132                         $this->assertRepoDefined();
1133                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1134                 }
1135                 return $this->hashPath;
1136         }
1137
1138         /**
1139          * Get the path of the file relative to the public zone root.
1140          * This function is overriden in OldLocalFile to be like getArchiveRel().
1141          *
1142          * @return string
1143          */
1144         function getRel() {
1145                 return $this->getHashPath() . $this->getName();
1146         }
1147
1148         /**
1149          * Get the path of an archived file relative to the public zone root
1150          *
1151          * @param $suffix bool|string if not false, the name of an archived thumbnail file
1152          *
1153          * @return string
1154          */
1155         function getArchiveRel( $suffix = false ) {
1156                 $path = 'archive/' . $this->getHashPath();
1157                 if ( $suffix === false ) {
1158                         $path = substr( $path, 0, -1 );
1159                 } else {
1160                         $path .= $suffix;
1161                 }
1162                 return $path;
1163         }
1164
1165         /**
1166          * Get the path, relative to the thumbnail zone root, of the
1167          * thumbnail directory or a particular file if $suffix is specified
1168          *
1169          * @param $suffix bool|string if not false, the name of a thumbnail file
1170          *
1171          * @return string
1172          */
1173         function getThumbRel( $suffix = false ) {
1174                 $path = $this->getRel();
1175                 if ( $suffix !== false ) {
1176                         $path .= '/' . $suffix;
1177                 }
1178                 return $path;
1179         }
1180
1181         /**
1182          * Get urlencoded path of the file relative to the public zone root.
1183          * This function is overriden in OldLocalFile to be like getArchiveUrl().
1184          *
1185          * @return string
1186          */
1187         function getUrlRel() {
1188                 return $this->getHashPath() . rawurlencode( $this->getName() );
1189         }
1190
1191         /**
1192          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1193          * or a specific thumb if the $suffix is given.
1194          *
1195          * @param $archiveName string the timestamped name of an archived image
1196          * @param $suffix bool|string if not false, the name of a thumbnail file
1197          *
1198          * @return string
1199          */
1200         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1201                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1202                 if ( $suffix === false ) {
1203                         $path = substr( $path, 0, -1 );
1204                 } else {
1205                         $path .= $suffix;
1206                 }
1207                 return $path;
1208         }
1209
1210         /**
1211          * Get the path of the archived file.
1212          *
1213          * @param $suffix bool|string if not false, the name of an archived file.
1214          *
1215          * @return string
1216          */
1217         function getArchivePath( $suffix = false ) {
1218                 $this->assertRepoDefined();
1219                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1220         }
1221
1222         /**
1223          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1224          *
1225          * @param $archiveName string the timestamped name of an archived image
1226          * @param $suffix bool|string if not false, the name of a thumbnail file
1227          *
1228          * @return string
1229          */
1230         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1231                 $this->assertRepoDefined();
1232                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1233                         $this->getArchiveThumbRel( $archiveName, $suffix );
1234         }
1235
1236         /**
1237          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1238          *
1239          * @param $suffix bool|string if not false, the name of a thumbnail file
1240          *
1241          * @return string
1242          */
1243         function getThumbPath( $suffix = false ) {
1244                 $this->assertRepoDefined();
1245                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1246         }
1247
1248         /**
1249          * Get the URL of the archive directory, or a particular file if $suffix is specified
1250          *
1251          * @param $suffix bool|string if not false, the name of an archived file
1252          *
1253          * @return string
1254          */
1255         function getArchiveUrl( $suffix = false ) {
1256                 $this->assertRepoDefined();
1257                 $ext = $this->getExtension();
1258                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1259                 if ( $suffix === false ) {
1260                         $path = substr( $path, 0, -1 );
1261                 } else {
1262                         $path .= rawurlencode( $suffix );
1263                 }
1264                 return $path;
1265         }
1266
1267         /**
1268          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1269          *
1270          * @param $archiveName string the timestamped name of an archived image
1271          * @param $suffix bool|string if not false, the name of a thumbnail file
1272          *
1273          * @return string
1274          */
1275         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1276                 $this->assertRepoDefined();
1277                 $ext = $this->getExtension();
1278                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1279                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1280                 if ( $suffix === false ) {
1281                         $path = substr( $path, 0, -1 );
1282                 } else {
1283                         $path .= rawurlencode( $suffix );
1284                 }
1285                 return $path;
1286         }
1287
1288         /**
1289          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1290          *
1291          * @param $suffix bool|string if not false, the name of a thumbnail file
1292          *
1293          * @return string path
1294          */
1295         function getThumbUrl( $suffix = false ) {
1296                 $this->assertRepoDefined();
1297                 $ext = $this->getExtension();
1298                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/' . $this->getUrlRel();
1299                 if ( $suffix !== false ) {
1300                         $path .= '/' . rawurlencode( $suffix );
1301                 }
1302                 return $path;
1303         }
1304
1305         /**
1306          * Get the public zone virtual URL for a current version source file
1307          *
1308          * @param $suffix bool|string if not false, the name of a thumbnail file
1309          *
1310          * @return string
1311          */
1312         function getVirtualUrl( $suffix = false ) {
1313                 $this->assertRepoDefined();
1314                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1315                 if ( $suffix !== false ) {
1316                         $path .= '/' . rawurlencode( $suffix );
1317                 }
1318                 return $path;
1319         }
1320
1321         /**
1322          * Get the public zone virtual URL for an archived version source file
1323          *
1324          * @param $suffix bool|string if not false, the name of a thumbnail file
1325          *
1326          * @return string
1327          */
1328         function getArchiveVirtualUrl( $suffix = false ) {
1329                 $this->assertRepoDefined();
1330                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1331                 if ( $suffix === false ) {
1332                         $path = substr( $path, 0, -1 );
1333                 } else {
1334                         $path .= rawurlencode( $suffix );
1335                 }
1336                 return $path;
1337         }
1338
1339         /**
1340          * Get the virtual URL for a thumbnail file or directory
1341          *
1342          * @param $suffix bool|string if not false, the name of a thumbnail file
1343          *
1344          * @return string
1345          */
1346         function getThumbVirtualUrl( $suffix = false ) {
1347                 $this->assertRepoDefined();
1348                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1349                 if ( $suffix !== false ) {
1350                         $path .= '/' . rawurlencode( $suffix );
1351                 }
1352                 return $path;
1353         }
1354
1355         /**
1356          * @return bool
1357          */
1358         function isHashed() {
1359                 $this->assertRepoDefined();
1360                 return (bool)$this->repo->getHashLevels();
1361         }
1362
1363         /**
1364          * @throws MWException
1365          */
1366         function readOnlyError() {
1367                 throw new MWException( get_class($this) . ': write operations are not supported' );
1368         }
1369
1370         /**
1371          * Record a file upload in the upload log and the image table
1372          * STUB
1373          * Overridden by LocalFile
1374          * @param $oldver
1375          * @param $desc
1376          * @param $license string
1377          * @param $copyStatus string
1378          * @param $source string
1379          * @param $watch bool
1380          */
1381         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
1382                 $this->readOnlyError();
1383         }
1384
1385         /**
1386          * Move or copy a file to its public location. If a file exists at the
1387          * destination, move it to an archive. Returns a FileRepoStatus object with
1388          * the archive name in the "value" member on success.
1389          *
1390          * The archive name should be passed through to recordUpload for database
1391          * registration.
1392          *
1393          * @param $srcPath String: local filesystem path to the source image
1394          * @param $flags Integer: a bitwise combination of:
1395          *     File::DELETE_SOURCE    Delete the source file, i.e. move
1396          *         rather than copy
1397          * @return FileRepoStatus object. On success, the value member contains the
1398          *     archive name, or an empty string if it was a new file.
1399          *
1400          * STUB
1401          * Overridden by LocalFile
1402          */
1403         function publish( $srcPath, $flags = 0 ) {
1404                 $this->readOnlyError();
1405         }
1406
1407         /**
1408          * @return bool
1409          */
1410         function formatMetadata() {
1411                 if ( !$this->getHandler() ) {
1412                         return false;
1413                 }
1414                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1415         }
1416
1417         /**
1418          * Returns true if the file comes from the local file repository.
1419          *
1420          * @return bool
1421          */
1422         function isLocal() {
1423                 return $this->repo && $this->repo->isLocal();
1424         }
1425
1426         /**
1427          * Returns the name of the repository.
1428          *
1429          * @return string
1430          */
1431         function getRepoName() {
1432                 return $this->repo ? $this->repo->getName() : 'unknown';
1433         }
1434
1435         /**
1436          * Returns the repository
1437          *
1438          * @return FileRepo|bool
1439          */
1440         function getRepo() {
1441                 return $this->repo;
1442         }
1443
1444         /**
1445          * Returns true if the image is an old version
1446          * STUB
1447          *
1448          * @return bool
1449          */
1450         function isOld() {
1451                 return false;
1452         }
1453
1454         /**
1455          * Is this file a "deleted" file in a private archive?
1456          * STUB
1457          *
1458          * @param $field
1459          *
1460          * @return bool
1461          */
1462         function isDeleted( $field ) {
1463                 return false;
1464         }
1465
1466         /**
1467          * Return the deletion bitfield
1468          * STUB
1469          * @return int
1470          */
1471         function getVisibility() {
1472                 return 0;
1473         }
1474
1475         /**
1476          * Was this file ever deleted from the wiki?
1477          *
1478          * @return bool
1479          */
1480         function wasDeleted() {
1481                 $title = $this->getTitle();
1482                 return $title && $title->isDeletedQuick();
1483         }
1484
1485         /**
1486          * Move file to the new title
1487          *
1488          * Move current, old version and all thumbnails
1489          * to the new filename. Old file is deleted.
1490          *
1491          * Cache purging is done; checks for validity
1492          * and logging are caller's responsibility
1493          *
1494          * @param $target Title New file name
1495          * @return FileRepoStatus object.
1496          */
1497          function move( $target ) {
1498                 $this->readOnlyError();
1499          }
1500
1501         /**
1502          * Delete all versions of the file.
1503          *
1504          * Moves the files into an archive directory (or deletes them)
1505          * and removes the database rows.
1506          *
1507          * Cache purging is done; logging is caller's responsibility.
1508          *
1509          * @param $reason String
1510          * @param $suppress Boolean: hide content from sysops?
1511          * @return bool on success, false on some kind of failure
1512          * STUB
1513          * Overridden by LocalFile
1514          */
1515         function delete( $reason, $suppress = false ) {
1516                 $this->readOnlyError();
1517         }
1518
1519         /**
1520          * Restore all or specified deleted revisions to the given file.
1521          * Permissions and logging are left to the caller.
1522          *
1523          * May throw database exceptions on error.
1524          *
1525          * @param $versions array set of record ids of deleted items to restore,
1526          *                    or empty to restore all revisions.
1527          * @param $unsuppress bool remove restrictions on content upon restoration?
1528          * @return int|bool the number of file revisions restored if successful,
1529          *         or false on failure
1530          * STUB
1531          * Overridden by LocalFile
1532          */
1533         function restore( $versions = array(), $unsuppress = false ) {
1534                 $this->readOnlyError();
1535         }
1536
1537         /**
1538          * Returns 'true' if this file is a type which supports multiple pages,
1539          * e.g. DJVU or PDF. Note that this may be true even if the file in
1540          * question only has a single page.
1541          *
1542          * @return Bool
1543          */
1544         function isMultipage() {
1545                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1546         }
1547
1548         /**
1549          * Returns the number of pages of a multipage document, or false for
1550          * documents which aren't multipage documents
1551          *
1552          * @return bool|int
1553          */
1554         function pageCount() {
1555                 if ( !isset( $this->pageCount ) ) {
1556                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1557                                 $this->pageCount = $this->handler->pageCount( $this );
1558                         } else {
1559                                 $this->pageCount = false;
1560                         }
1561                 }
1562                 return $this->pageCount;
1563         }
1564
1565         /**
1566          * Calculate the height of a thumbnail using the source and destination width
1567          *
1568          * @param $srcWidth
1569          * @param $srcHeight
1570          * @param $dstWidth
1571          *
1572          * @return int
1573          */
1574         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1575                 // Exact integer multiply followed by division
1576                 if ( $srcWidth == 0 ) {
1577                         return 0;
1578                 } else {
1579                         return round( $srcHeight * $dstWidth / $srcWidth );
1580                 }
1581         }
1582
1583         /**
1584          * Get an image size array like that returned by getImageSize(), or false if it
1585          * can't be determined.
1586          *
1587          * @param $fileName String: The filename
1588          * @return Array
1589          */
1590         function getImageSize( $fileName ) {
1591                 if ( !$this->getHandler() ) {
1592                         return false;
1593                 }
1594                 return $this->handler->getImageSize( $this, $fileName );
1595         }
1596
1597         /**
1598          * Get the URL of the image description page. May return false if it is
1599          * unknown or not applicable.
1600          *
1601          * @return string
1602          */
1603         function getDescriptionUrl() {
1604                 if ( $this->repo ) {
1605                         return $this->repo->getDescriptionUrl( $this->getName() );
1606                 } else {
1607                         return false;
1608                 }
1609         }
1610
1611         /**
1612          * Get the HTML text of the description page, if available
1613          *
1614          * @return string
1615          */
1616         function getDescriptionText() {
1617                 global $wgMemc, $wgLang;
1618                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1619                         return false;
1620                 }
1621                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1622                 if ( $renderUrl ) {
1623                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1624                                 wfDebug("Attempting to get the description from cache...");
1625                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1626                                                                         $this->getName() );
1627                                 $obj = $wgMemc->get($key);
1628                                 if ($obj) {
1629                                         wfDebug("success!\n");
1630                                         return $obj;
1631                                 }
1632                                 wfDebug("miss\n");
1633                         }
1634                         wfDebug( "Fetching shared description from $renderUrl\n" );
1635                         $res = Http::get( $renderUrl );
1636                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1637                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1638                         }
1639                         return $res;
1640                 } else {
1641                         return false;
1642                 }
1643         }
1644
1645         /**
1646          * Get description of file revision
1647          * STUB
1648          *
1649          * @param $audience Integer: one of:
1650          *      File::FOR_PUBLIC       to be displayed to all users
1651          *      File::FOR_THIS_USER    to be displayed to the given user
1652          *      File::RAW              get the description regardless of permissions
1653          * @param $user User object to check for, only if FOR_THIS_USER is passed
1654          *              to the $audience parameter
1655          * @return string
1656          */
1657         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
1658                 return null;
1659         }
1660
1661         /**
1662          * Get the 14-character timestamp of the file upload
1663          *
1664          * @return string|bool TS_MW timestamp or false on failure
1665          */
1666         function getTimestamp() {
1667                 $this->assertRepoDefined();
1668                 return $this->repo->getFileTimestamp( $this->getPath() );
1669         }
1670
1671         /**
1672          * Get the SHA-1 base 36 hash of the file
1673          *
1674          * @return string
1675          */
1676         function getSha1() {
1677                 $this->assertRepoDefined();
1678                 return $this->repo->getFileSha1( $this->getPath() );
1679         }
1680
1681         /**
1682          * Get the deletion archive key, "<sha1>.<ext>"
1683          *
1684          * @return string
1685          */
1686         function getStorageKey() {
1687                 $hash = $this->getSha1();
1688                 if ( !$hash ) {
1689                         return false;
1690                 }
1691                 $ext = $this->getExtension();
1692                 $dotExt = $ext === '' ? '' : ".$ext";
1693                 return $hash . $dotExt;
1694         }
1695
1696         /**
1697          * Determine if the current user is allowed to view a particular
1698          * field of this file, if it's marked as deleted.
1699          * STUB
1700          * @param $field Integer
1701          * @param $user User object to check, or null to use $wgUser
1702          * @return Boolean
1703          */
1704         function userCan( $field, User $user = null ) {
1705                 return true;
1706         }
1707
1708         /**
1709          * Get an associative array containing information about a file in the local filesystem.
1710          *
1711          * @param $path String: absolute local filesystem path
1712          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1713          *             Set it to false to ignore the extension.
1714          *
1715          * @return array
1716          */
1717         static function getPropsFromPath( $path, $ext = true ) {
1718                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1719                 wfDeprecated( __METHOD__, '1.19' );
1720
1721                 $fsFile = new FSFile( $path );
1722                 return $fsFile->getProps();
1723         }
1724
1725         /**
1726          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1727          * encoding, zero padded to 31 digits.
1728          *
1729          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1730          * fairly neatly.
1731          *
1732          * @param $path string
1733          *
1734          * @return bool|string False on failure
1735          */
1736         static function sha1Base36( $path ) {
1737                 wfDeprecated( __METHOD__, '1.19' );
1738
1739                 $fsFile = new FSFile( $path );
1740                 return $fsFile->getSha1Base36();
1741         }
1742
1743         /**
1744          * @return string
1745          */
1746         function getLongDesc() {
1747                 $handler = $this->getHandler();
1748                 if ( $handler ) {
1749                         return $handler->getLongDesc( $this );
1750                 } else {
1751                         return MediaHandler::getGeneralLongDesc( $this );
1752                 }
1753         }
1754
1755         /**
1756          * @return string
1757          */
1758         function getShortDesc() {
1759                 $handler = $this->getHandler();
1760                 if ( $handler ) {
1761                         return $handler->getShortDesc( $this );
1762                 } else {
1763                         return MediaHandler::getGeneralShortDesc( $this );
1764                 }
1765         }
1766
1767         /**
1768          * @return string
1769          */
1770         function getDimensionsString() {
1771                 $handler = $this->getHandler();
1772                 if ( $handler ) {
1773                         return $handler->getDimensionsString( $this );
1774                 } else {
1775                         return '';
1776                 }
1777         }
1778
1779         /**
1780          * @return
1781          */
1782         function getRedirected() {
1783                 return $this->redirected;
1784         }
1785
1786         /**
1787          * @return Title
1788          */
1789         function getRedirectedTitle() {
1790                 if ( $this->redirected ) {
1791                         if ( !$this->redirectTitle ) {
1792                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1793                         }
1794                         return $this->redirectTitle;
1795                 }
1796         }
1797
1798         /**
1799          * @param  $from
1800          * @return void
1801          */
1802         function redirectedFrom( $from ) {
1803                 $this->redirected = $from;
1804         }
1805
1806         /**
1807          * @return bool
1808          */
1809         function isMissing() {
1810                 return false;
1811         }
1812
1813         /**
1814          * Check if this file object is small and can be cached
1815          * @return boolean
1816          */
1817         public function isCacheable() {
1818                 return true;
1819         }
1820
1821         /**
1822          * Assert that $this->repo is set to a valid FileRepo instance
1823          * @throws MWException
1824          */
1825         protected function assertRepoDefined() {
1826                 if ( !( $this->repo instanceof $this->repoClass ) ) {
1827                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
1828                 }
1829         }
1830
1831         /**
1832          * Assert that $this->title is set to a Title
1833          * @throws MWException
1834          */
1835         protected function assertTitleDefined() {
1836                 if ( !( $this->title instanceof Title ) ) {
1837                         throw new MWException( "A Title object is not set for this File.\n" );
1838                 }
1839         }
1840 }