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         // Bitfield values akin to the Revision deletion constants
  52         const DELETED_FILE = 1;
  53         const DELETED_COMMENT = 2;
  54         const DELETED_USER = 4;
  55         const DELETED_RESTRICTED = 8;
  56
  57         /** Force rendering in the current process */
  58         const RENDER_NOW = 1;
  59         /**
  60          * Force rendering even if thumbnail already exist and using RENDER_NOW
  61          * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
  62          */
  63         const RENDER_FORCE = 2;
  64
  65         const DELETE_SOURCE = 1;
  66
  67         // Audience options for File::getDescription()
  68         const FOR_PUBLIC = 1;
  69         const FOR_THIS_USER = 2;
  70         const RAW = 3;
  71
  72         // Options for File::thumbName()
  73         const THUMB_FULL_NAME = 1;
  74
  75         /**
  76          * Some member variables can be lazy-initialised using __get(). The
  77          * initialisation function for these variables is always a function named
  78          * like getVar(), where Var is the variable name with upper-case first
  79          * letter.
  80          *
  81          * The following variables are initialised in this way in this base class:
  82          *    name, extension, handler, path, canRender, isSafeFile,
  83          *    transformScript, hashPath, pageCount, url
  84          *
  85          * Code within this class should generally use the accessor function
  86          * directly, since __get() isn't re-entrant and therefore causes bugs that
  87          * depend on initialisation order.
  88          */
  89
  90         /**
  91          * The following member variables are not lazy-initialised
  92          */
  93
  94         /** @var FileRepo|LocalRepo|ForeignAPIRepo|bool */
  95         public $repo;
  96
  97         /** @var Title|string|bool */
  98         protected $title;
  99
 100         /** @var string Text of last error  */
 101         protected $lastError;
 102
 103         /** @var string Main part of the title, with underscores (Title::getDBkey)  */
 104         protected $redirected;
 105
 106         /** @var Title */
 107         protected $redirectedTitle;
 108
 109         /** @var FSFile|bool False if undefined */
 110         protected $fsFile;
 111
 112         /** @var MediaHandler */
 113         protected $handler;
 114
 115         /** @var string The URL corresponding to one of the four basic zones */
 116         protected $url;
 117
 118         /** @var string File extension */
 119         protected $extension;
 120
 121         /** @var string The name of a file from its title object */
 122         protected $name;
 123
 124         /** @var string The storage path corresponding to one of the zones */
 125         protected $path;
 126
 127         /** @var string Relative path including trailing slash */
 128         protected $hashPath;
 129
 130         /** @var string number of pages of a multipage document, or false for
 131          *    documents which aren't multipage documents
 132          */
 133         protected $pageCount;
 134
 135         /** @var string URL of transformscript (for example thumb.php) */
 136         protected $transformScript;
 137
 138         /** @var Title */
 139         protected $redirectTitle;
 140
 141         /** @var bool Wether the output of transform() for this file is likely to be valid. */
 142         protected $canRender;
 143
 144         /** @var bool Wether this media file is in a format that is unlikely to
 145          *    contain viruses or malicious content
 146          */
 147         protected $isSafeFile;
 148
 149         /** @var string Required Repository class type */
 150         protected $repoClass = 'FileRepo';
 151
 152         /**
 153          * Call this constructor from child classes.
 154          *
 155          * Both $title and $repo are optional, though some functions
 156          * may return false or throw exceptions if they are not set.
 157          * Most subclasses will want to call assertRepoDefined() here.
 158          *
 159          * @param Title|string|bool $title
 160          * @param FileRepo|bool $repo
 161          */
 162         function __construct( $title, $repo ) {
 163                 if ( $title !== false ) { // subclasses may not use MW titles
 164                         $title = self::normalizeTitle( $title, 'exception' );
 165                 }
 166                 $this->title = $title;
 167                 $this->repo = $repo;
 168         }
 169
 170         /**
 171          * Given a string or Title object return either a
 172          * valid Title object with namespace NS_FILE or null
 173          *
 174          * @param Title|string $title
 175          * @param string|bool $exception Use 'exception' to throw an error on bad titles
 176          * @throws MWException
 177          * @return Title|null
 178          */
 179         static function normalizeTitle( $title, $exception = false ) {
 180                 $ret = $title;
 181                 if ( $ret instanceof Title ) {
 182                         # Normalize NS_MEDIA -> NS_FILE
 183                         if ( $ret->getNamespace() == NS_MEDIA ) {
 184                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 185                         # Sanity check the title namespace
 186                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 187                                 $ret = null;
 188                         }
 189                 } else {
 190                         # Convert strings to Title objects
 191                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 192                 }
 193                 if ( !$ret && $exception !== false ) {
 194                         throw new MWException( "`$title` is not a valid file title." );
 195                 }
 196
 197                 return $ret;
 198         }
 199
 200         function __get( $name ) {
 201                 $function = array( $this, 'get' . ucfirst( $name ) );
 202                 if ( !is_callable( $function ) ) {
 203                         return null;
 204                 } else {
 205                         $this->$name = call_user_func( $function );
 206
 207                         return $this->$name;
 208                 }
 209         }
 210
 211         /**
 212          * Normalize a file extension to the common form, and ensure it's clean.
 213          * Extensions with non-alphanumeric characters will be discarded.
 214          *
 215          * @param string $ext (without the .)
 216          * @return string
 217          */
 218         static function normalizeExtension( $ext ) {
 219                 $lower = strtolower( $ext );
 220                 $squish = array(
 221                         'htm' => 'html',
 222                         'jpeg' => 'jpg',
 223                         'mpeg' => 'mpg',
 224                         'tiff' => 'tif',
 225                         'ogv' => 'ogg' );
 226                 if ( isset( $squish[$lower] ) ) {
 227                         return $squish[$lower];
 228                 } elseif ( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 229                         return $lower;
 230                 } else {
 231                         return '';
 232                 }
 233         }
 234
 235         /**
 236          * Checks if file extensions are compatible
 237          *
 238          * @param File $old Old file
 239          * @param string $new New name
 240          *
 241          * @return bool|null
 242          */
 243         static function checkExtensionCompatibility( File $old, $new ) {
 244                 $oldMime = $old->getMimeType();
 245                 $n = strrpos( $new, '.' );
 246                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 247                 $mimeMagic = MimeMagic::singleton();
 248
 249                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 250         }
 251
 252         /**
 253          * Upgrade the database row if there is one
 254          * Called by ImagePage
 255          * STUB
 256          */
 257         function upgradeRow() {
 258         }
 259
 260         /**
 261          * Split an internet media type into its two components; if not
 262          * a two-part name, set the minor type to 'unknown'.
 263          *
 264          * @param string $mime "text/html" etc
 265          * @return array ("text", "html") etc
 266          */
 267         public static function splitMime( $mime ) {
 268                 if ( strpos( $mime, '/' ) !== false ) {
 269                         return explode( '/', $mime, 2 );
 270                 } else {
 271                         return array( $mime, 'unknown' );
 272                 }
 273         }
 274
 275         /**
 276          * Callback for usort() to do file sorts by name
 277          *
 278          * @param File $a
 279          * @param File $b
 280          * @return int Result of name comparison
 281          */
 282         public static function compare( File $a, File $b ) {
 283                 return strcmp( $a->getName(), $b->getName() );
 284         }
 285
 286         /**
 287          * Return the name of this file
 288          *
 289          * @return string
 290          */
 291         public function getName() {
 292                 if ( !isset( $this->name ) ) {
 293                         $this->assertRepoDefined();
 294                         $this->name = $this->repo->getNameFromTitle( $this->title );
 295                 }
 296
 297                 return $this->name;
 298         }
 299
 300         /**
 301          * Get the file extension, e.g. "svg"
 302          *
 303          * @return string
 304          */
 305         function getExtension() {
 306                 if ( !isset( $this->extension ) ) {
 307                         $n = strrpos( $this->getName(), '.' );
 308                         $this->extension = self::normalizeExtension(
 309                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 310                 }
 311
 312                 return $this->extension;
 313         }
 314
 315         /**
 316          * Return the associated title object
 317          *
 318          * @return Title
 319          */
 320         public function getTitle() {
 321                 return $this->title;
 322         }
 323
 324         /**
 325          * Return the title used to find this file
 326          *
 327          * @return Title
 328          */
 329         public function getOriginalTitle() {
 330                 if ( $this->redirected ) {
 331                         return $this->getRedirectedTitle();
 332                 }
 333
 334                 return $this->title;
 335         }
 336
 337         /**
 338          * Return the URL of the file
 339          *
 340          * @return string
 341          */
 342         public function getUrl() {
 343                 if ( !isset( $this->url ) ) {
 344                         $this->assertRepoDefined();
 345                         $ext = $this->getExtension();
 346                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 347                 }
 348
 349                 return $this->url;
 350         }
 351
 352         /**
 353          * Return a fully-qualified URL to the file.
 354          * Upload URL paths _may or may not_ be fully qualified, so
 355          * we check. Local paths are assumed to belong on $wgServer.
 356          *
 357          * @return string
 358          */
 359         public function getFullUrl() {
 360                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 361         }
 362
 363         /**
 364          * @return string
 365          */
 366         public function getCanonicalUrl() {
 367                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 368         }
 369
 370         /**
 371          * @return string
 372          */
 373         function getViewURL() {
 374                 if ( $this->mustRender() ) {
 375                         if ( $this->canRender() ) {
 376                                 return $this->createThumb( $this->getWidth() );
 377                         } else {
 378                                 wfDebug( __METHOD__ . ': supposed to render ' . $this->getName() .
 379                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 380
 381                                 return $this->getURL(); #hm... return NULL?
 382                         }
 383                 } else {
 384                         return $this->getURL();
 385                 }
 386         }
 387
 388         /**
 389          * Return the storage path to the file. Note that this does
 390          * not mean that a file actually exists under that location.
 391          *
 392          * This path depends on whether directory hashing is active or not,
 393          * i.e. whether the files are all found in the same directory,
 394          * or in hashed paths like /images/3/3c.
 395          *
 396          * Most callers don't check the return value, but ForeignAPIFile::getPath
 397          * returns false.
 398          *
 399          * @return string|bool ForeignAPIFile::getPath can return false
 400          */
 401         public function getPath() {
 402                 if ( !isset( $this->path ) ) {
 403                         $this->assertRepoDefined();
 404                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 405                 }
 406
 407                 return $this->path;
 408         }
 409
 410         /**
 411          * Get an FS copy or original of this file and return the path.
 412          * Returns false on failure. Callers must not alter the file.
 413          * Temporary files are cleared automatically.
 414          *
 415          * @return string|bool False on failure
 416          */
 417         public function getLocalRefPath() {
 418                 $this->assertRepoDefined();
 419                 if ( !isset( $this->fsFile ) ) {
 420                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 421                         if ( !$this->fsFile ) {
 422                                 $this->fsFile = false; // null => false; cache negative hits
 423                         }
 424                 }
 425
 426                 return ( $this->fsFile )
 427                         ? $this->fsFile->getPath()
 428                         : false;
 429         }
 430
 431         /**
 432          * Return the width of the image. Returns false if the width is unknown
 433          * or undefined.
 434          *
 435          * STUB
 436          * Overridden by LocalFile, UnregisteredLocalFile
 437          *
 438          * @param int $page
 439          * @return int|bool
 440          */
 441         public function getWidth( $page = 1 ) {
 442                 return false;
 443         }
 444
 445         /**
 446          * Return the height of the image. Returns false if the height is unknown
 447          * or undefined
 448          *
 449          * STUB
 450          * Overridden by LocalFile, UnregisteredLocalFile
 451          *
 452          * @param int $page
 453          * @return bool|int False on failure
 454          */
 455         public function getHeight( $page = 1 ) {
 456                 return false;
 457         }
 458
 459         /**
 460          * Returns ID or name of user who uploaded the file
 461          * STUB
 462          *
 463          * @param string $type 'text' or 'id'
 464          * @return string|int
 465          */
 466         public function getUser( $type = 'text' ) {
 467                 return null;
 468         }
 469
 470         /**
 471          * Get the duration of a media file in seconds
 472          *
 473          * @return int
 474          */
 475         public function getLength() {
 476                 $handler = $this->getHandler();
 477                 if ( $handler ) {
 478                         return $handler->getLength( $this );
 479                 } else {
 480                         return 0;
 481                 }
 482         }
 483
 484         /**
 485          * Return true if the file is vectorized
 486          *
 487          * @return bool
 488          */
 489         public function isVectorized() {
 490                 $handler = $this->getHandler();
 491                 if ( $handler ) {
 492                         return $handler->isVectorized( $this );
 493                 } else {
 494                         return false;
 495                 }
 496         }
 497
 498         /**
 499          * Gives a (possibly empty) list of languages to render
 500          * the file in.
 501          *
 502          * If the file doesn't have translations, or if the file
 503          * format does not support that sort of thing, returns
 504          * an empty array.
 505          *
 506          * @return Array
 507          * @since 1.23
 508          */
 509         public function getAvailableLanguages() {
 510                 $handler = $this->getHandler();
 511                 if ( $handler ) {
 512                         return $handler->getAvailableLanguages( $this );
 513                 } else {
 514                         return array();
 515                 }
 516         }
 517
 518         /**
 519          * In files that support multiple language, what is the default language
 520          * to use if none specified.
 521          *
 522          * @return String lang code, or null if filetype doesn't support multiple languages.
 523          * @since 1.23
 524          */
 525         public function getDefaultRenderLanguage() {
 526                 $handler = $this->getHandler();
 527                 if ( $handler ) {
 528                         return $handler->getDefaultRenderLanguage( $this );
 529                 } else {
 530                         return null;
 531                 }
 532         }
 533
 534         /**
 535          * Will the thumbnail be animated if one would expect it to be.
 536          *
 537          * Currently used to add a warning to the image description page
 538          *
 539          * @return bool false if the main image is both animated
 540          *   and the thumbnail is not. In all other cases must return
 541          *   true. If image is not renderable whatsoever, should
 542          *   return true.
 543          */
 544         public function canAnimateThumbIfAppropriate() {
 545                 $handler = $this->getHandler();
 546                 if ( !$handler ) {
 547                         // We cannot handle image whatsoever, thus
 548                         // one would not expect it to be animated
 549                         // so true.
 550                         return true;
 551                 } else {
 552                         if ( $this->allowInlineDisplay()
 553                                 && $handler->isAnimatedImage( $this )
 554                                 && !$handler->canAnimateThumbnail( $this )
 555                         ) {
 556                                 // Image is animated, but thumbnail isn't.
 557                                 // This is unexpected to the user.
 558                                 return false;
 559                         } else {
 560                                 // Image is not animated, so one would
 561                                 // not expect thumb to be
 562                                 return true;
 563                         }
 564                 }
 565         }
 566
 567         /**
 568          * Get handler-specific metadata
 569          * Overridden by LocalFile, UnregisteredLocalFile
 570          * STUB
 571          * @return bool|array
 572          */
 573         public function getMetadata() {
 574                 return false;
 575         }
 576
 577         /**
 578          * Like getMetadata but returns a handler independent array of common values.
 579          * @see MediaHandler::getCommonMetaArray()
 580          * @return array|bool Array or false if not supported
 581          * @since 1.23
 582          */
 583         public function getCommonMetaArray() {
 584                 $handler = $this->getHandler();
 585
 586                 return $handler->getCommonMetaArray( $this );
 587         }
 588
 589         /**
 590          * get versioned metadata
 591          *
 592          * @param array|string $metadata Array or string of (serialized) metadata
 593          * @param int $version Version number.
 594          * @return array Array containing metadata, or what was passed to it on fail
 595          *   (unserializing if not array)
 596          */
 597         public function convertMetadataVersion( $metadata, $version ) {
 598                 $handler = $this->getHandler();
 599                 if ( !is_array( $metadata ) ) {
 600                         // Just to make the return type consistent
 601                         $metadata = unserialize( $metadata );
 602                 }
 603                 if ( $handler ) {
 604                         return $handler->convertMetadataVersion( $metadata, $version );
 605                 } else {
 606                         return $metadata;
 607                 }
 608         }
 609
 610         /**
 611          * Return the bit depth of the file
 612          * Overridden by LocalFile
 613          * STUB
 614          * @return int
 615          */
 616         public function getBitDepth() {
 617                 return 0;
 618         }
 619
 620         /**
 621          * Return the size of the image file, in bytes
 622          * Overridden by LocalFile, UnregisteredLocalFile
 623          * STUB
 624          * @return bool
 625          */
 626         public function getSize() {
 627                 return false;
 628         }
 629
 630         /**
 631          * Returns the mime type of the file.
 632          * Overridden by LocalFile, UnregisteredLocalFile
 633          * STUB
 634          *
 635          * @return string
 636          */
 637         function getMimeType() {
 638                 return 'unknown/unknown';
 639         }
 640
 641         /**
 642          * Return the type of the media in the file.
 643          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 644          * Overridden by LocalFile,
 645          * STUB
 646          * @return string
 647          */
 648         function getMediaType() {
 649                 return MEDIATYPE_UNKNOWN;
 650         }
 651
 652         /**
 653          * Checks if the output of transform() for this file is likely
 654          * to be valid. If this is false, various user elements will
 655          * display a placeholder instead.
 656          *
 657          * Currently, this checks if the file is an image format
 658          * that can be converted to a format
 659          * supported by all browsers (namely GIF, PNG and JPEG),
 660          * or if it is an SVG image and SVG conversion is enabled.
 661          *
 662          * @return bool
 663          */
 664         function canRender() {
 665                 if ( !isset( $this->canRender ) ) {
 666                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 667                 }
 668
 669                 return $this->canRender;
 670         }
 671
 672         /**
 673          * Accessor for __get()
 674          * @return bool
 675          */
 676         protected function getCanRender() {
 677                 return $this->canRender();
 678         }
 679
 680         /**
 681          * Return true if the file is of a type that can't be directly
 682          * rendered by typical browsers and needs to be re-rasterized.
 683          *
 684          * This returns true for everything but the bitmap types
 685          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 686          * also return true for any non-image formats.
 687          *
 688          * @return bool
 689          */
 690         function mustRender() {
 691                 return $this->getHandler() && $this->handler->mustRender( $this );
 692         }
 693
 694         /**
 695          * Alias for canRender()
 696          *
 697          * @return bool
 698          */
 699         function allowInlineDisplay() {
 700                 return $this->canRender();
 701         }
 702
 703         /**
 704          * Determines if this media file is in a format that is unlikely to
 705          * contain viruses or malicious content. It uses the global
 706          * $wgTrustedMediaFormats list to determine if the file is safe.
 707          *
 708          * This is used to show a warning on the description page of non-safe files.
 709          * It may also be used to disallow direct [[media:...]] links to such files.
 710          *
 711          * Note that this function will always return true if allowInlineDisplay()
 712          * or isTrustedFile() is true for this file.
 713          *
 714          * @return bool
 715          */
 716         function isSafeFile() {
 717                 if ( !isset( $this->isSafeFile ) ) {
 718                         $this->isSafeFile = $this->getIsSafeFileUncached();
 719                 }
 720
 721                 return $this->isSafeFile;
 722         }
 723
 724         /**
 725          * Accessor for __get()
 726          *
 727          * @return bool
 728          */
 729         protected function getIsSafeFile() {
 730                 return $this->isSafeFile();
 731         }
 732
 733         /**
 734          * Uncached accessor
 735          *
 736          * @return bool
 737          */
 738         protected function getIsSafeFileUncached() {
 739                 global $wgTrustedMediaFormats;
 740
 741                 if ( $this->allowInlineDisplay() ) {
 742                         return true;
 743                 }
 744                 if ( $this->isTrustedFile() ) {
 745                         return true;
 746                 }
 747
 748                 $type = $this->getMediaType();
 749                 $mime = $this->getMimeType();
 750                 #wfDebug( "LocalFile::isSafeFile: type= $type, mime= $mime\n" );
 751
 752                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 753                         return false; #unknown type, not trusted
 754                 }
 755                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 756                         return true;
 757                 }
 758
 759                 if ( $mime === "unknown/unknown" ) {
 760                         return false; #unknown type, not trusted
 761                 }
 762                 if ( in_array( $mime, $wgTrustedMediaFormats ) ) {
 763                         return true;
 764                 }
 765
 766                 return false;
 767         }
 768
 769         /**
 770          * Returns true if the file is flagged as trusted. Files flagged that way
 771          * can be linked to directly, even if that is not allowed for this type of
 772          * file normally.
 773          *
 774          * This is a dummy function right now and always returns false. It could be
 775          * implemented to extract a flag from the database. The trusted flag could be
 776          * set on upload, if the user has sufficient privileges, to bypass script-
 777          * and html-filters. It may even be coupled with cryptographics signatures
 778          * or such.
 779          *
 780          * @return bool
 781          */
 782         function isTrustedFile() {
 783                 #this could be implemented to check a flag in the database,
 784                 #look for signatures, etc
 785                 return false;
 786         }
 787
 788         /**
 789          * Returns true if file exists in the repository.
 790          *
 791          * Overridden by LocalFile to avoid unnecessary stat calls.
 792          *
 793          * @return bool Whether file exists in the repository.
 794          */
 795         public function exists() {
 796                 return $this->getPath() && $this->repo->fileExists( $this->path );
 797         }
 798
 799         /**
 800          * Returns true if file exists in the repository and can be included in a page.
 801          * It would be unsafe to include private images, making public thumbnails inadvertently
 802          *
 803          * @return bool Whether file exists in the repository and is includable.
 804          */
 805         public function isVisible() {
 806                 return $this->exists();
 807         }
 808
 809         /**
 810          * @return string
 811          */
 812         function getTransformScript() {
 813                 if ( !isset( $this->transformScript ) ) {
 814                         $this->transformScript = false;
 815                         if ( $this->repo ) {
 816                                 $script = $this->repo->getThumbScriptUrl();
 817                                 if ( $script ) {
 818                                         $this->transformScript = wfAppendQuery( $script, array( 'f' => $this->getName() ) );
 819                                 }
 820                         }
 821                 }
 822
 823                 return $this->transformScript;
 824         }
 825
 826         /**
 827          * Get a ThumbnailImage which is the same size as the source
 828          *
 829          * @param array $handlerParams
 830          *
 831          * @return string
 832          */
 833         function getUnscaledThumb( $handlerParams = array() ) {
 834                 $hp =& $handlerParams;
 835                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 836                 $width = $this->getWidth( $page );
 837                 if ( !$width ) {
 838                         return $this->iconThumb();
 839                 }
 840                 $hp['width'] = $width;
 841
 842                 return $this->transform( $hp );
 843         }
 844
 845         /**
 846          * Return the file name of a thumbnail with the specified parameters.
 847          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 848          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 849          *
 850          * @param array $params handler-specific parameters
 851          * @param int $flags Bitfield that supports THUMB_* constants
 852          * @return string
 853          */
 854         public function thumbName( $params, $flags = 0 ) {
 855                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 856                         ? $this->repo->nameForThumb( $this->getName() )
 857                         : $this->getName();
 858
 859                 return $this->generateThumbName( $name, $params );
 860         }
 861
 862         /**
 863          * Generate a thumbnail file name from a name and specified parameters
 864          *
 865          * @param string $name
 866          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 867          * @return string
 868          */
 869         public function generateThumbName( $name, $params ) {
 870                 if ( !$this->getHandler() ) {
 871                         return null;
 872                 }
 873                 $extension = $this->getExtension();
 874                 list( $thumbExt, ) = $this->handler->getThumbType(
 875                         $extension, $this->getMimeType(), $params );
 876                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 877                 if ( $thumbExt != $extension ) {
 878                         $thumbName .= ".$thumbExt";
 879                 }
 880
 881                 return $thumbName;
 882         }
 883
 884         /**
 885          * Create a thumbnail of the image having the specified width/height.
 886          * The thumbnail will not be created if the width is larger than the
 887          * image's width. Let the browser do the scaling in this case.
 888          * The thumbnail is stored on disk and is only computed if the thumbnail
 889          * file does not exist OR if it is older than the image.
 890          * Returns the URL.
 891          *
 892          * Keeps aspect ratio of original image. If both width and height are
 893          * specified, the generated image will be no bigger than width x height,
 894          * and will also have correct aspect ratio.
 895          *
 896          * @param int $width Maximum width of the generated thumbnail
 897          * @param int $height Maximum height of the image (optional)
 898          *
 899          * @return string
 900          */
 901         public function createThumb( $width, $height = -1 ) {
 902                 $params = array( 'width' => $width );
 903                 if ( $height != -1 ) {
 904                         $params['height'] = $height;
 905                 }
 906                 $thumb = $this->transform( $params );
 907                 if ( !$thumb || $thumb->isError() ) {
 908                         return '';
 909                 }
 910
 911                 return $thumb->getUrl();
 912         }
 913
 914         /**
 915          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 916          *
 917          * @param string $thumbPath Thumbnail storage path
 918          * @param string $thumbUrl Thumbnail URL
 919          * @param array $params
 920          * @param int $flags
 921          * @return MediaTransformOutput
 922          */
 923         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 924                 global $wgIgnoreImageErrors;
 925
 926                 $handler = $this->getHandler();
 927                 if ( $handler && $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 928                         return $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 929                 } else {
 930                         return new MediaTransformError( 'thumbnail_error',
 931                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 932                 }
 933         }
 934
 935         /**
 936          * Transform a media file
 937          *
 938          * @param array $params an associative array of handler-specific parameters.
 939          *   Typical keys are width, height and page.
 940          * @param int $flags A bitfield, may contain self::RENDER_NOW to force rendering
 941          * @return MediaTransformOutput|bool False on failure
 942          */
 943         function transform( $params, $flags = 0 ) {
 944                 global $wgUseSquid, $wgIgnoreImageErrors, $wgThumbnailEpoch;
 945
 946                 wfProfileIn( __METHOD__ );
 947                 do {
 948                         if ( !$this->canRender() ) {
 949                                 $thumb = $this->iconThumb();
 950                                 break; // not a bitmap or renderable image, don't try
 951                         }
 952
 953                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 954                         $descriptionUrl = $this->getDescriptionUrl();
 955                         if ( $descriptionUrl ) {
 956                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
 957                         }
 958
 959                         $handler = $this->getHandler();
 960                         $script = $this->getTransformScript();
 961                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
 962                                 // Use a script to transform on client request, if possible
 963                                 $thumb = $handler->getScriptedTransform( $this, $script, $params );
 964                                 if ( $thumb ) {
 965                                         break;
 966                                 }
 967                         }
 968
 969                         $normalisedParams = $params;
 970                         $handler->normaliseParams( $this, $normalisedParams );
 971
 972                         $thumbName = $this->thumbName( $normalisedParams );
 973                         $thumbUrl = $this->getThumbUrl( $thumbName );
 974                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
 975
 976                         if ( $this->repo ) {
 977                                 // Defer rendering if a 404 handler is set up...
 978                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
 979                                         wfDebug( __METHOD__ . " transformation deferred." );
 980                                         // XXX: Pass in the storage path even though we are not rendering anything
 981                                         // and the path is supposed to be an FS path. This is due to getScalerType()
 982                                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
 983                                         $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 984                                         break;
 985                                 }
 986                                 // Clean up broken thumbnails as needed
 987                                 $this->migrateThumbFile( $thumbName );
 988                                 // Check if an up-to-date thumbnail already exists...
 989                                 wfDebug( __METHOD__ . ": Doing stat for $thumbPath\n" );
 990                                 if ( !( $flags & self::RENDER_FORCE ) && $this->repo->fileExists( $thumbPath ) ) {
 991                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
 992                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
 993                                                 // XXX: Pass in the storage path even though we are not rendering anything
 994                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
 995                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
 996                                                 $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 997                                                 $thumb->setStoragePath( $thumbPath );
 998                                                 break;
 999                                         }
1000                                 } elseif ( $flags & self::RENDER_FORCE ) {
1001                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
1002                                 }
1003                         }
1004
1005                         // If the backend is ready-only, don't keep generating thumbnails
1006                         // only to return transformation errors, just return the error now.
1007                         if ( $this->repo->getReadOnlyReason() !== false ) {
1008                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1009                                 break;
1010                         }
1011
1012                         // Create a temp FS file with the same extension and the thumbnail
1013                         $thumbExt = FileBackend::extensionFromPath( $thumbPath );
1014                         $tmpFile = TempFSFile::factory( 'transform_', $thumbExt );
1015                         if ( !$tmpFile ) {
1016                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1017                                 break;
1018                         }
1019                         $tmpThumbPath = $tmpFile->getPath(); // path of 0-byte temp file
1020
1021                         // Actually render the thumbnail...
1022                         wfProfileIn( __METHOD__ . '-doTransform' );
1023                         $thumb = $handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $params );
1024                         wfProfileOut( __METHOD__ . '-doTransform' );
1025                         $tmpFile->bind( $thumb ); // keep alive with $thumb
1026
1027                         if ( !$thumb ) { // bad params?
1028                                 $thumb = null;
1029                         } elseif ( $thumb->isError() ) { // transform error
1030                                 $this->lastError = $thumb->toText();
1031                                 // Ignore errors if requested
1032                                 if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
1033                                         $thumb = $handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $params );
1034                                 }
1035                         } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
1036                                 // Copy the thumbnail from the file system into storage...
1037                                 $disposition = $this->getThumbDisposition( $thumbName );
1038                                 $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
1039                                 if ( $status->isOK() ) {
1040                                         $thumb->setStoragePath( $thumbPath );
1041                                 } else {
1042                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1043                                 }
1044                                 // Give extensions a chance to do something with this thumbnail...
1045                                 wfRunHooks( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
1046                         }
1047
1048                         // Purge. Useful in the event of Core -> Squid connection failure or squid
1049                         // purge collisions from elsewhere during failure. Don't keep triggering for
1050                         // "thumbs" which have the main image URL though (bug 13776)
1051                         if ( $wgUseSquid ) {
1052                                 if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
1053                                         SquidUpdate::purge( array( $thumbUrl ) );
1054                                 }
1055                         }
1056                 } while ( false );
1057
1058                 wfProfileOut( __METHOD__ );
1059
1060                 return is_object( $thumb ) ? $thumb : false;
1061         }
1062
1063         /**
1064          * @param string $thumbName Thumbnail name
1065          * @return string Content-Disposition header value
1066          */
1067         function getThumbDisposition( $thumbName ) {
1068                 $fileName = $this->name; // file name to suggest
1069                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
1070                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
1071                         $fileName .= ".$thumbExt";
1072                 }
1073
1074                 return FileBackend::makeContentDisposition( 'inline', $fileName );
1075         }
1076
1077         /**
1078          * Hook into transform() to allow migration of thumbnail files
1079          * STUB
1080          * Overridden by LocalFile
1081          */
1082         function migrateThumbFile( $thumbName ) {
1083         }
1084
1085         /**
1086          * Get a MediaHandler instance for this file
1087          *
1088          * @return MediaHandler|bool Registered MediaHandler for file's MIME type
1089          *   or false if none found
1090          */
1091         function getHandler() {
1092                 if ( !isset( $this->handler ) ) {
1093                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1094                 }
1095
1096                 return $this->handler;
1097         }
1098
1099         /**
1100          * Get a ThumbnailImage representing a file type icon
1101          *
1102          * @return ThumbnailImage
1103          */
1104         function iconThumb() {
1105                 global $wgStylePath, $wgStyleDirectory;
1106
1107                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1108                 foreach ( $try as $icon ) {
1109                         $path = '/common/images/icons/' . $icon;
1110                         $filepath = $wgStyleDirectory . $path;
1111                         if ( file_exists( $filepath ) ) { // always FS
1112                                 $params = array( 'width' => 120, 'height' => 120 );
1113
1114                                 return new ThumbnailImage( $this, $wgStylePath . $path, false, $params );
1115                         }
1116                 }
1117
1118                 return null;
1119         }
1120
1121         /**
1122          * Get last thumbnailing error.
1123          * Largely obsolete.
1124          */
1125         function getLastError() {
1126                 return $this->lastError;
1127         }
1128
1129         /**
1130          * Get all thumbnail names previously generated for this file
1131          * STUB
1132          * Overridden by LocalFile
1133          * @return array
1134          */
1135         function getThumbnails() {
1136                 return array();
1137         }
1138
1139         /**
1140          * Purge shared caches such as thumbnails and DB data caching
1141          * STUB
1142          * Overridden by LocalFile
1143          * @param array $options Options, which include:
1144          *   'forThumbRefresh' : The purging is only to refresh thumbnails
1145          */
1146         function purgeCache( $options = array() ) {
1147         }
1148
1149         /**
1150          * Purge the file description page, but don't go after
1151          * pages using the file. Use when modifying file history
1152          * but not the current data.
1153          */
1154         function purgeDescription() {
1155                 $title = $this->getTitle();
1156                 if ( $title ) {
1157                         $title->invalidateCache();
1158                         $title->purgeSquid();
1159                 }
1160         }
1161
1162         /**
1163          * Purge metadata and all affected pages when the file is created,
1164          * deleted, or majorly updated.
1165          */
1166         function purgeEverything() {
1167                 // Delete thumbnails and refresh file metadata cache
1168                 $this->purgeCache();
1169                 $this->purgeDescription();
1170
1171                 // Purge cache of all pages using this file
1172                 $title = $this->getTitle();
1173                 if ( $title ) {
1174                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1175                         $update->doUpdate();
1176                 }
1177         }
1178
1179         /**
1180          * Return a fragment of the history of file.
1181          *
1182          * STUB
1183          * @param int $limit Limit of rows to return
1184          * @param string $start timestamp Only revisions older than $start will be returned
1185          * @param string $end timestamp Only revisions newer than $end will be returned
1186          * @param bool $inc Include the endpoints of the time range
1187          *
1188          * @return array
1189          */
1190         function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
1191                 return array();
1192         }
1193
1194         /**
1195          * Return the history of this file, line by line. Starts with current version,
1196          * then old versions. Should return an object similar to an image/oldimage
1197          * database row.
1198          *
1199          * STUB
1200          * Overridden in LocalFile
1201          * @return bool
1202          */
1203         public function nextHistoryLine() {
1204                 return false;
1205         }
1206
1207         /**
1208          * Reset the history pointer to the first element of the history.
1209          * Always call this function after using nextHistoryLine() to free db resources
1210          * STUB
1211          * Overridden in LocalFile.
1212          */
1213         public function resetHistory() {
1214         }
1215
1216         /**
1217          * Get the filename hash component of the directory including trailing slash,
1218          * e.g. f/fa/
1219          * If the repository is not hashed, returns an empty string.
1220          *
1221          * @return string
1222          */
1223         function getHashPath() {
1224                 if ( !isset( $this->hashPath ) ) {
1225                         $this->assertRepoDefined();
1226                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1227                 }
1228
1229                 return $this->hashPath;
1230         }
1231
1232         /**
1233          * Get the path of the file relative to the public zone root.
1234          * This function is overriden in OldLocalFile to be like getArchiveRel().
1235          *
1236          * @return string
1237          */
1238         function getRel() {
1239                 return $this->getHashPath() . $this->getName();
1240         }
1241
1242         /**
1243          * Get the path of an archived file relative to the public zone root
1244          *
1245          * @param bool|string $suffix if not false, the name of an archived thumbnail file
1246          *
1247          * @return string
1248          */
1249         function getArchiveRel( $suffix = false ) {
1250                 $path = 'archive/' . $this->getHashPath();
1251                 if ( $suffix === false ) {
1252                         $path = substr( $path, 0, -1 );
1253                 } else {
1254                         $path .= $suffix;
1255                 }
1256
1257                 return $path;
1258         }
1259
1260         /**
1261          * Get the path, relative to the thumbnail zone root, of the
1262          * thumbnail directory or a particular file if $suffix is specified
1263          *
1264          * @param bool|string $suffix if not false, the name of a thumbnail file
1265          * @return string
1266          */
1267         function getThumbRel( $suffix = false ) {
1268                 $path = $this->getRel();
1269                 if ( $suffix !== false ) {
1270                         $path .= '/' . $suffix;
1271                 }
1272
1273                 return $path;
1274         }
1275
1276         /**
1277          * Get urlencoded path of the file relative to the public zone root.
1278          * This function is overriden in OldLocalFile to be like getArchiveUrl().
1279          *
1280          * @return string
1281          */
1282         function getUrlRel() {
1283                 return $this->getHashPath() . rawurlencode( $this->getName() );
1284         }
1285
1286         /**
1287          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1288          * or a specific thumb if the $suffix is given.
1289          *
1290          * @param string $archiveName the timestamped name of an archived image
1291          * @param bool|string $suffix if not false, the name of a thumbnail file
1292          * @return string
1293          */
1294         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1295                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1296                 if ( $suffix === false ) {
1297                         $path = substr( $path, 0, -1 );
1298                 } else {
1299                         $path .= $suffix;
1300                 }
1301
1302                 return $path;
1303         }
1304
1305         /**
1306          * Get the path of the archived file.
1307          *
1308          * @param bool|string $suffix if not false, the name of an archived file.
1309          * @return string
1310          */
1311         function getArchivePath( $suffix = false ) {
1312                 $this->assertRepoDefined();
1313
1314                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1315         }
1316
1317         /**
1318          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1319          *
1320          * @param string $archiveName the timestamped name of an archived image
1321          * @param bool|string $suffix if not false, the name of a thumbnail file
1322          * @return string
1323          */
1324         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1325                 $this->assertRepoDefined();
1326
1327                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1328                         $this->getArchiveThumbRel( $archiveName, $suffix );
1329         }
1330
1331         /**
1332          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1333          *
1334          * @param bool|string $suffix If not false, the name of a thumbnail file
1335          * @return string
1336          */
1337         function getThumbPath( $suffix = false ) {
1338                 $this->assertRepoDefined();
1339
1340                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1341         }
1342
1343         /**
1344          * Get the path of the transcoded directory, or a particular file if $suffix is specified
1345          *
1346          * @param bool|string $suffix If not false, the name of a media file
1347          * @return string
1348          */
1349         function getTranscodedPath( $suffix = false ) {
1350                 $this->assertRepoDefined();
1351
1352                 return $this->repo->getZonePath( 'transcoded' ) . '/' . $this->getThumbRel( $suffix );
1353         }
1354
1355         /**
1356          * Get the URL of the archive directory, or a particular file if $suffix is specified
1357          *
1358          * @param bool|string $suffix If not false, the name of an archived file
1359          * @return string
1360          */
1361         function getArchiveUrl( $suffix = false ) {
1362                 $this->assertRepoDefined();
1363                 $ext = $this->getExtension();
1364                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1365                 if ( $suffix === false ) {
1366                         $path = substr( $path, 0, -1 );
1367                 } else {
1368                         $path .= rawurlencode( $suffix );
1369                 }
1370
1371                 return $path;
1372         }
1373
1374         /**
1375          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1376          *
1377          * @param string $archiveName the timestamped name of an archived image
1378          * @param bool|string $suffix If not false, the name of a thumbnail file
1379          * @return string
1380          */
1381         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1382                 $this->assertRepoDefined();
1383                 $ext = $this->getExtension();
1384                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1385                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1386                 if ( $suffix === false ) {
1387                         $path = substr( $path, 0, -1 );
1388                 } else {
1389                         $path .= rawurlencode( $suffix );
1390                 }
1391
1392                 return $path;
1393         }
1394
1395         /**
1396          * Get the URL of the zone directory, or a particular file if $suffix is specified
1397          *
1398          * @param string $zone name of requested zone
1399          * @param bool|string $suffix If not false, the name of a file in zone
1400          * @return string path
1401          */
1402         function getZoneUrl( $zone, $suffix = false ) {
1403                 $this->assertRepoDefined();
1404                 $ext = $this->getExtension();
1405                 $path = $this->repo->getZoneUrl( $zone, $ext ) . '/' . $this->getUrlRel();
1406                 if ( $suffix !== false ) {
1407                         $path .= '/' . rawurlencode( $suffix );
1408                 }
1409
1410                 return $path;
1411         }
1412
1413         /**
1414          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1415          *
1416          * @param bool|string $suffix if not false, the name of a thumbnail file
1417          * @return string path
1418          */
1419         function getThumbUrl( $suffix = false ) {
1420                 return $this->getZoneUrl( 'thumb', $suffix );
1421         }
1422
1423         /**
1424          * Get the URL of the transcoded directory, or a particular file if $suffix is specified
1425          *
1426          * @param bool|string $suffix If not false, the name of a media file
1427          * @return string path
1428          */
1429         function getTranscodedUrl( $suffix = false ) {
1430                 return $this->getZoneUrl( 'transcoded', $suffix );
1431         }
1432
1433         /**
1434          * Get the public zone virtual URL for a current version source file
1435          *
1436          * @param bool|string $suffix If not false, the name of a thumbnail file
1437          * @return string
1438          */
1439         function getVirtualUrl( $suffix = false ) {
1440                 $this->assertRepoDefined();
1441                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1442                 if ( $suffix !== false ) {
1443                         $path .= '/' . rawurlencode( $suffix );
1444                 }
1445
1446                 return $path;
1447         }
1448
1449         /**
1450          * Get the public zone virtual URL for an archived version source file
1451          *
1452          * @param bool|string $suffix If not false, the name of a thumbnail file
1453          * @return string
1454          */
1455         function getArchiveVirtualUrl( $suffix = false ) {
1456                 $this->assertRepoDefined();
1457                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1458                 if ( $suffix === false ) {
1459                         $path = substr( $path, 0, -1 );
1460                 } else {
1461                         $path .= rawurlencode( $suffix );
1462                 }
1463
1464                 return $path;
1465         }
1466
1467         /**
1468          * Get the virtual URL for a thumbnail file or directory
1469          *
1470          * @param bool|string $suffix If not false, the name of a thumbnail file
1471          * @return string
1472          */
1473         function getThumbVirtualUrl( $suffix = false ) {
1474                 $this->assertRepoDefined();
1475                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1476                 if ( $suffix !== false ) {
1477                         $path .= '/' . rawurlencode( $suffix );
1478                 }
1479
1480                 return $path;
1481         }
1482
1483         /**
1484          * @return bool
1485          */
1486         function isHashed() {
1487                 $this->assertRepoDefined();
1488
1489                 return (bool)$this->repo->getHashLevels();
1490         }
1491
1492         /**
1493          * @throws MWException
1494          */
1495         function readOnlyError() {
1496                 throw new MWException( get_class( $this ) . ': write operations are not supported' );
1497         }
1498
1499         /**
1500          * Record a file upload in the upload log and the image table
1501          * STUB
1502          * Overridden by LocalFile
1503          * @param $oldver
1504          * @param $desc
1505          * @param string $license
1506          * @param string $copyStatus
1507          * @param string $source
1508          * @param bool $watch
1509          * @param string|bool $timestamp
1510          * @param null|User $user User object or null to use $wgUser
1511          * @return bool
1512          * @throws MWException
1513          */
1514         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
1515                 $watch = false, $timestamp = false, User $user = null
1516         ) {
1517                 $this->readOnlyError();
1518         }
1519
1520         /**
1521          * Move or copy a file to its public location. If a file exists at the
1522          * destination, move it to an archive. Returns a FileRepoStatus object with
1523          * the archive name in the "value" member on success.
1524          *
1525          * The archive name should be passed through to recordUpload for database
1526          * registration.
1527          *
1528          * Options to $options include:
1529          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1530          *
1531          * @param string $srcPath local filesystem path to the source image
1532          * @param int $flags A bitwise combination of:
1533          *   File::DELETE_SOURCE    Delete the source file, i.e. move rather than copy
1534          * @param array $options Optional additional parameters
1535          * @return FileRepoStatus object. On success, the value member contains the
1536          *   archive name, or an empty string if it was a new file.
1537          *
1538          * STUB
1539          * Overridden by LocalFile
1540          */
1541         function publish( $srcPath, $flags = 0, array $options = array() ) {
1542                 $this->readOnlyError();
1543         }
1544
1545         /**
1546          * @return bool
1547          */
1548         function formatMetadata() {
1549                 if ( !$this->getHandler() ) {
1550                         return false;
1551                 }
1552
1553                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1554         }
1555
1556         /**
1557          * Returns true if the file comes from the local file repository.
1558          *
1559          * @return bool
1560          */
1561         function isLocal() {
1562                 return $this->repo && $this->repo->isLocal();
1563         }
1564
1565         /**
1566          * Returns the name of the repository.
1567          *
1568          * @return string
1569          */
1570         function getRepoName() {
1571                 return $this->repo ? $this->repo->getName() : 'unknown';
1572         }
1573
1574         /**
1575          * Returns the repository
1576          *
1577          * @return FileRepo|LocalRepo|bool
1578          */
1579         function getRepo() {
1580                 return $this->repo;
1581         }
1582
1583         /**
1584          * Returns true if the image is an old version
1585          * STUB
1586          *
1587          * @return bool
1588          */
1589         function isOld() {
1590                 return false;
1591         }
1592
1593         /**
1594          * Is this file a "deleted" file in a private archive?
1595          * STUB
1596          *
1597          * @param int $field one of DELETED_* bitfield constants
1598          * @return bool
1599          */
1600         function isDeleted( $field ) {
1601                 return false;
1602         }
1603
1604         /**
1605          * Return the deletion bitfield
1606          * STUB
1607          * @return int
1608          */
1609         function getVisibility() {
1610                 return 0;
1611         }
1612
1613         /**
1614          * Was this file ever deleted from the wiki?
1615          *
1616          * @return bool
1617          */
1618         function wasDeleted() {
1619                 $title = $this->getTitle();
1620
1621                 return $title && $title->isDeletedQuick();
1622         }
1623
1624         /**
1625          * Move file to the new title
1626          *
1627          * Move current, old version and all thumbnails
1628          * to the new filename. Old file is deleted.
1629          *
1630          * Cache purging is done; checks for validity
1631          * and logging are caller's responsibility
1632          *
1633          * @param Title $target New file name
1634          * @return FileRepoStatus object.
1635          */
1636         function move( $target ) {
1637                 $this->readOnlyError();
1638         }
1639
1640         /**
1641          * Delete all versions of the file.
1642          *
1643          * Moves the files into an archive directory (or deletes them)
1644          * and removes the database rows.
1645          *
1646          * Cache purging is done; logging is caller's responsibility.
1647          *
1648          * @param string $reason
1649          * @param bool $suppress Hide content from sysops?
1650          * @return bool on success, false on some kind of failure
1651          * STUB
1652          * Overridden by LocalFile
1653          */
1654         function delete( $reason, $suppress = false ) {
1655                 $this->readOnlyError();
1656         }
1657
1658         /**
1659          * Restore all or specified deleted revisions to the given file.
1660          * Permissions and logging are left to the caller.
1661          *
1662          * May throw database exceptions on error.
1663          *
1664          * @param array $versions set of record ids of deleted items to restore,
1665          *   or empty to restore all revisions.
1666          * @param bool $unsuppress remove restrictions on content upon restoration?
1667          * @return int|bool the number of file revisions restored if successful,
1668          *   or false on failure
1669          * STUB
1670          * Overridden by LocalFile
1671          */
1672         function restore( $versions = array(), $unsuppress = false ) {
1673                 $this->readOnlyError();
1674         }
1675
1676         /**
1677          * Returns 'true' if this file is a type which supports multiple pages,
1678          * e.g. DJVU or PDF. Note that this may be true even if the file in
1679          * question only has a single page.
1680          *
1681          * @return bool
1682          */
1683         function isMultipage() {
1684                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1685         }
1686
1687         /**
1688          * Returns the number of pages of a multipage document, or false for
1689          * documents which aren't multipage documents
1690          *
1691          * @return bool|int
1692          */
1693         function pageCount() {
1694                 if ( !isset( $this->pageCount ) ) {
1695                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1696                                 $this->pageCount = $this->handler->pageCount( $this );
1697                         } else {
1698                                 $this->pageCount = false;
1699                         }
1700                 }
1701
1702                 return $this->pageCount;
1703         }
1704
1705         /**
1706          * Calculate the height of a thumbnail using the source and destination width
1707          *
1708          * @param int $srcWidth
1709          * @param int $srcHeight
1710          * @param int $dstWidth
1711          *
1712          * @return int
1713          */
1714         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1715                 // Exact integer multiply followed by division
1716                 if ( $srcWidth == 0 ) {
1717                         return 0;
1718                 } else {
1719                         return round( $srcHeight * $dstWidth / $srcWidth );
1720                 }
1721         }
1722
1723         /**
1724          * Get an image size array like that returned by getImageSize(), or false if it
1725          * can't be determined.
1726          *
1727          * @param string $fileName The filename
1728          * @return array
1729          */
1730         function getImageSize( $fileName ) {
1731                 if ( !$this->getHandler() ) {
1732                         return false;
1733                 }
1734
1735                 return $this->handler->getImageSize( $this, $fileName );
1736         }
1737
1738         /**
1739          * Get the URL of the image description page. May return false if it is
1740          * unknown or not applicable.
1741          *
1742          * @return string
1743          */
1744         function getDescriptionUrl() {
1745                 if ( $this->repo ) {
1746                         return $this->repo->getDescriptionUrl( $this->getName() );
1747                 } else {
1748                         return false;
1749                 }
1750         }
1751
1752         /**
1753          * Get the HTML text of the description page, if available
1754          *
1755          * @param bool|Language $lang Optional language to fetch description in
1756          * @return string
1757          */
1758         function getDescriptionText( $lang = false ) {
1759                 global $wgMemc, $wgLang;
1760                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1761                         return false;
1762                 }
1763                 if ( !$lang ) {
1764                         $lang = $wgLang;
1765                 }
1766                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $lang->getCode() );
1767                 if ( $renderUrl ) {
1768                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1769                                 wfDebug( "Attempting to get the description from cache..." );
1770                                 $key = $this->repo->getLocalCacheKey(
1771                                         'RemoteFileDescription',
1772                                         'url',
1773                                         $lang->getCode(),
1774                                         $this->getName()
1775                                 );
1776                                 $obj = $wgMemc->get( $key );
1777                                 if ( $obj ) {
1778                                         wfDebug( "success!\n" );
1779
1780                                         return $obj;
1781                                 }
1782                                 wfDebug( "miss\n" );
1783                         }
1784                         wfDebug( "Fetching shared description from $renderUrl\n" );
1785                         $res = Http::get( $renderUrl );
1786                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1787                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1788                         }
1789
1790                         return $res;
1791                 } else {
1792                         return false;
1793                 }
1794         }
1795
1796         /**
1797          * Get description of file revision
1798          * STUB
1799          *
1800          * @param int $audience One of:
1801          *   File::FOR_PUBLIC       to be displayed to all users
1802          *   File::FOR_THIS_USER    to be displayed to the given user
1803          *   File::RAW              get the description regardless of permissions
1804          * @param User $user User object to check for, only if FOR_THIS_USER is
1805          *   passed to the $audience parameter
1806          * @return string
1807          */
1808         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
1809                 return null;
1810         }
1811
1812         /**
1813          * Get the 14-character timestamp of the file upload
1814          *
1815          * @return string|bool TS_MW timestamp or false on failure
1816          */
1817         function getTimestamp() {
1818                 $this->assertRepoDefined();
1819
1820                 return $this->repo->getFileTimestamp( $this->getPath() );
1821         }
1822
1823         /**
1824          * Get the SHA-1 base 36 hash of the file
1825          *
1826          * @return string
1827          */
1828         function getSha1() {
1829                 $this->assertRepoDefined();
1830
1831                 return $this->repo->getFileSha1( $this->getPath() );
1832         }
1833
1834         /**
1835          * Get the deletion archive key, "<sha1>.<ext>"
1836          *
1837          * @return string
1838          */
1839         function getStorageKey() {
1840                 $hash = $this->getSha1();
1841                 if ( !$hash ) {
1842                         return false;
1843                 }
1844                 $ext = $this->getExtension();
1845                 $dotExt = $ext === '' ? '' : ".$ext";
1846
1847                 return $hash . $dotExt;
1848         }
1849
1850         /**
1851          * Determine if the current user is allowed to view a particular
1852          * field of this file, if it's marked as deleted.
1853          * STUB
1854          * @param int $field
1855          * @param User $user User object to check, or null to use $wgUser
1856          * @return bool
1857          */
1858         function userCan( $field, User $user = null ) {
1859                 return true;
1860         }
1861
1862         /**
1863          * Get an associative array containing information about a file in the local filesystem.
1864          *
1865          * @param string $path absolute local filesystem path
1866          * @param string|bool $ext The file extension, or true to extract it from
1867          *   the filename. Set it to false to ignore the extension.
1868          *
1869          * @return array
1870          * @deprecated since 1.19
1871          */
1872         static function getPropsFromPath( $path, $ext = true ) {
1873                 wfDebug( __METHOD__ . ": Getting file info for $path\n" );
1874                 wfDeprecated( __METHOD__, '1.19' );
1875
1876                 $fsFile = new FSFile( $path );
1877
1878                 return $fsFile->getProps();
1879         }
1880
1881         /**
1882          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1883          * encoding, zero padded to 31 digits.
1884          *
1885          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1886          * fairly neatly.
1887          *
1888          * @param $path string
1889          * @return bool|string False on failure
1890          * @deprecated since 1.19
1891          */
1892         static function sha1Base36( $path ) {
1893                 wfDeprecated( __METHOD__, '1.19' );
1894
1895                 $fsFile = new FSFile( $path );
1896
1897                 return $fsFile->getSha1Base36();
1898         }
1899
1900         /**
1901          * @return array HTTP header name/value map to use for HEAD/GET request responses
1902          */
1903         function getStreamHeaders() {
1904                 $handler = $this->getHandler();
1905                 if ( $handler ) {
1906                         return $handler->getStreamHeaders( $this->getMetadata() );
1907                 } else {
1908                         return array();
1909                 }
1910         }
1911
1912         /**
1913          * @return string
1914          */
1915         function getLongDesc() {
1916                 $handler = $this->getHandler();
1917                 if ( $handler ) {
1918                         return $handler->getLongDesc( $this );
1919                 } else {
1920                         return MediaHandler::getGeneralLongDesc( $this );
1921                 }
1922         }
1923
1924         /**
1925          * @return string
1926          */
1927         function getShortDesc() {
1928                 $handler = $this->getHandler();
1929                 if ( $handler ) {
1930                         return $handler->getShortDesc( $this );
1931                 } else {
1932                         return MediaHandler::getGeneralShortDesc( $this );
1933                 }
1934         }
1935
1936         /**
1937          * @return string
1938          */
1939         function getDimensionsString() {
1940                 $handler = $this->getHandler();
1941                 if ( $handler ) {
1942                         return $handler->getDimensionsString( $this );
1943                 } else {
1944                         return '';
1945                 }
1946         }
1947
1948         /**
1949          * @return string
1950          */
1951         function getRedirected() {
1952                 return $this->redirected;
1953         }
1954
1955         /**
1956          * @return Title|null
1957          */
1958         function getRedirectedTitle() {
1959                 if ( $this->redirected ) {
1960                         if ( !$this->redirectTitle ) {
1961                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1962                         }
1963
1964                         return $this->redirectTitle;
1965                 }
1966
1967                 return null;
1968         }
1969
1970         /**
1971          * @param string $from
1972          * @return void
1973          */
1974         function redirectedFrom( $from ) {
1975                 $this->redirected = $from;
1976         }
1977
1978         /**
1979          * @return bool
1980          */
1981         function isMissing() {
1982                 return false;
1983         }
1984
1985         /**
1986          * Check if this file object is small and can be cached
1987          * @return bool
1988          */
1989         public function isCacheable() {
1990                 return true;
1991         }
1992
1993         /**
1994          * Assert that $this->repo is set to a valid FileRepo instance
1995          * @throws MWException
1996          */
1997         protected function assertRepoDefined() {
1998                 if ( !( $this->repo instanceof $this->repoClass ) ) {
1999                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
2000                 }
2001         }
2002
2003         /**
2004          * Assert that $this->title is set to a Title
2005          * @throws MWException
2006          */
2007         protected function assertTitleDefined() {
2008                 if ( !( $this->title instanceof Title ) ) {
2009                         throw new MWException( "A Title object is not set for this File.\n" );
2010                 }
2011         }
2012 }