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 Whether the output of transform() for this file is likely to be valid. */
 142         protected $canRender;
 143
 144         /** @var bool Whether 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         /** @var array Cache of tmp filepaths pointing to generated bucket thumbnails, keyed by width */
 153         protected $tmpBucketedThumbCache = array();
 154
 155         /**
 156          * Call this constructor from child classes.
 157          *
 158          * Both $title and $repo are optional, though some functions
 159          * may return false or throw exceptions if they are not set.
 160          * Most subclasses will want to call assertRepoDefined() here.
 161          *
 162          * @param Title|string|bool $title
 163          * @param FileRepo|bool $repo
 164          */
 165         function __construct( $title, $repo ) {
 166                 if ( $title !== false ) { // subclasses may not use MW titles
 167                         $title = self::normalizeTitle( $title, 'exception' );
 168                 }
 169                 $this->title = $title;
 170                 $this->repo = $repo;
 171         }
 172
 173         /**
 174          * Given a string or Title object return either a
 175          * valid Title object with namespace NS_FILE or null
 176          *
 177          * @param Title|string $title
 178          * @param string|bool $exception Use 'exception' to throw an error on bad titles
 179          * @throws MWException
 180          * @return Title|null
 181          */
 182         static function normalizeTitle( $title, $exception = false ) {
 183                 $ret = $title;
 184                 if ( $ret instanceof Title ) {
 185                         # Normalize NS_MEDIA -> NS_FILE
 186                         if ( $ret->getNamespace() == NS_MEDIA ) {
 187                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 188                         # Sanity check the title namespace
 189                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 190                                 $ret = null;
 191                         }
 192                 } else {
 193                         # Convert strings to Title objects
 194                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 195                 }
 196                 if ( !$ret && $exception !== false ) {
 197                         throw new MWException( "`$title` is not a valid file title." );
 198                 }
 199
 200                 return $ret;
 201         }
 202
 203         function __get( $name ) {
 204                 $function = array( $this, 'get' . ucfirst( $name ) );
 205                 if ( !is_callable( $function ) ) {
 206                         return null;
 207                 } else {
 208                         $this->$name = call_user_func( $function );
 209
 210                         return $this->$name;
 211                 }
 212         }
 213
 214         /**
 215          * Normalize a file extension to the common form, and ensure it's clean.
 216          * Extensions with non-alphanumeric characters will be discarded.
 217          *
 218          * @param string $ext (without the .)
 219          * @return string
 220          */
 221         static function normalizeExtension( $ext ) {
 222                 $lower = strtolower( $ext );
 223                 $squish = array(
 224                         'htm' => 'html',
 225                         'jpeg' => 'jpg',
 226                         'mpeg' => 'mpg',
 227                         'tiff' => 'tif',
 228                         'ogv' => 'ogg' );
 229                 if ( isset( $squish[$lower] ) ) {
 230                         return $squish[$lower];
 231                 } elseif ( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 232                         return $lower;
 233                 } else {
 234                         return '';
 235                 }
 236         }
 237
 238         /**
 239          * Checks if file extensions are compatible
 240          *
 241          * @param File $old Old file
 242          * @param string $new New name
 243          *
 244          * @return bool|null
 245          */
 246         static function checkExtensionCompatibility( File $old, $new ) {
 247                 $oldMime = $old->getMimeType();
 248                 $n = strrpos( $new, '.' );
 249                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 250                 $mimeMagic = MimeMagic::singleton();
 251
 252                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 253         }
 254
 255         /**
 256          * Upgrade the database row if there is one
 257          * Called by ImagePage
 258          * STUB
 259          */
 260         function upgradeRow() {
 261         }
 262
 263         /**
 264          * Split an internet media type into its two components; if not
 265          * a two-part name, set the minor type to 'unknown'.
 266          *
 267          * @param string $mime "text/html" etc
 268          * @return array ("text", "html") etc
 269          */
 270         public static function splitMime( $mime ) {
 271                 if ( strpos( $mime, '/' ) !== false ) {
 272                         return explode( '/', $mime, 2 );
 273                 } else {
 274                         return array( $mime, 'unknown' );
 275                 }
 276         }
 277
 278         /**
 279          * Callback for usort() to do file sorts by name
 280          *
 281          * @param File $a
 282          * @param File $b
 283          * @return int Result of name comparison
 284          */
 285         public static function compare( File $a, File $b ) {
 286                 return strcmp( $a->getName(), $b->getName() );
 287         }
 288
 289         /**
 290          * Return the name of this file
 291          *
 292          * @return string
 293          */
 294         public function getName() {
 295                 if ( !isset( $this->name ) ) {
 296                         $this->assertRepoDefined();
 297                         $this->name = $this->repo->getNameFromTitle( $this->title );
 298                 }
 299
 300                 return $this->name;
 301         }
 302
 303         /**
 304          * Get the file extension, e.g. "svg"
 305          *
 306          * @return string
 307          */
 308         function getExtension() {
 309                 if ( !isset( $this->extension ) ) {
 310                         $n = strrpos( $this->getName(), '.' );
 311                         $this->extension = self::normalizeExtension(
 312                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 313                 }
 314
 315                 return $this->extension;
 316         }
 317
 318         /**
 319          * Return the associated title object
 320          *
 321          * @return Title
 322          */
 323         public function getTitle() {
 324                 return $this->title;
 325         }
 326
 327         /**
 328          * Return the title used to find this file
 329          *
 330          * @return Title
 331          */
 332         public function getOriginalTitle() {
 333                 if ( $this->redirected ) {
 334                         return $this->getRedirectedTitle();
 335                 }
 336
 337                 return $this->title;
 338         }
 339
 340         /**
 341          * Return the URL of the file
 342          *
 343          * @return string
 344          */
 345         public function getUrl() {
 346                 if ( !isset( $this->url ) ) {
 347                         $this->assertRepoDefined();
 348                         $ext = $this->getExtension();
 349                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 350                 }
 351
 352                 return $this->url;
 353         }
 354
 355         /**
 356          * Return a fully-qualified URL to the file.
 357          * Upload URL paths _may or may not_ be fully qualified, so
 358          * we check. Local paths are assumed to belong on $wgServer.
 359          *
 360          * @return string
 361          */
 362         public function getFullUrl() {
 363                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 364         }
 365
 366         /**
 367          * @return string
 368          */
 369         public function getCanonicalUrl() {
 370                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 371         }
 372
 373         /**
 374          * @return string
 375          */
 376         function getViewURL() {
 377                 if ( $this->mustRender() ) {
 378                         if ( $this->canRender() ) {
 379                                 return $this->createThumb( $this->getWidth() );
 380                         } else {
 381                                 wfDebug( __METHOD__ . ': supposed to render ' . $this->getName() .
 382                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 383
 384                                 return $this->getURL(); #hm... return NULL?
 385                         }
 386                 } else {
 387                         return $this->getURL();
 388                 }
 389         }
 390
 391         /**
 392          * Return the storage path to the file. Note that this does
 393          * not mean that a file actually exists under that location.
 394          *
 395          * This path depends on whether directory hashing is active or not,
 396          * i.e. whether the files are all found in the same directory,
 397          * or in hashed paths like /images/3/3c.
 398          *
 399          * Most callers don't check the return value, but ForeignAPIFile::getPath
 400          * returns false.
 401          *
 402          * @return string|bool ForeignAPIFile::getPath can return false
 403          */
 404         public function getPath() {
 405                 if ( !isset( $this->path ) ) {
 406                         $this->assertRepoDefined();
 407                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 408                 }
 409
 410                 return $this->path;
 411         }
 412
 413         /**
 414          * Get an FS copy or original of this file and return the path.
 415          * Returns false on failure. Callers must not alter the file.
 416          * Temporary files are cleared automatically.
 417          *
 418          * @return string|bool False on failure
 419          */
 420         public function getLocalRefPath() {
 421                 $this->assertRepoDefined();
 422                 if ( !isset( $this->fsFile ) ) {
 423                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 424                         if ( !$this->fsFile ) {
 425                                 $this->fsFile = false; // null => false; cache negative hits
 426                         }
 427                 }
 428
 429                 return ( $this->fsFile )
 430                         ? $this->fsFile->getPath()
 431                         : false;
 432         }
 433
 434         /**
 435          * Return the width of the image. Returns false if the width is unknown
 436          * or undefined.
 437          *
 438          * STUB
 439          * Overridden by LocalFile, UnregisteredLocalFile
 440          *
 441          * @param int $page
 442          * @return int|bool
 443          */
 444         public function getWidth( $page = 1 ) {
 445                 return false;
 446         }
 447
 448         /**
 449          * Return the height of the image. Returns false if the height is unknown
 450          * or undefined
 451          *
 452          * STUB
 453          * Overridden by LocalFile, UnregisteredLocalFile
 454          *
 455          * @param int $page
 456          * @return bool|int False on failure
 457          */
 458         public function getHeight( $page = 1 ) {
 459                 return false;
 460         }
 461
 462         /**
 463          * Return the smallest bucket from $wgThumbnailBuckets which is at least
 464          * $wgThumbnailMinimumBucketDistance larger than $desiredWidth. The returned bucket, if any,
 465          * will always be bigger than $desiredWidth.
 466          *
 467          * @param int $desiredWidth
 468          * @param int $page
 469          * @return bool|int
 470          */
 471         public function getThumbnailBucket( $desiredWidth, $page = 1 ) {
 472                 global $wgThumbnailBuckets, $wgThumbnailMinimumBucketDistance;
 473
 474                 wfDebugLog( 'thumbnail', 'thumbnail buckets ' . json_encode( $wgThumbnailBuckets ) );
 475
 476                 $imageWidth = $this->getWidth( $page );
 477
 478                 if ( $imageWidth === false ) {
 479                         return false;
 480                 }
 481
 482                 if ( $desiredWidth > $imageWidth ) {
 483                         return false;
 484                 }
 485
 486                 if ( !$wgThumbnailBuckets ) {
 487                         return false;
 488                 }
 489
 490                 $sortedBuckets = $wgThumbnailBuckets;
 491
 492                 sort( $sortedBuckets );
 493
 494                 foreach ( $sortedBuckets as $bucket ) {
 495                         if ( $bucket >= $imageWidth ) {
 496                                 return false;
 497                         }
 498
 499                         if ( $bucket - $wgThumbnailMinimumBucketDistance > $desiredWidth ) {
 500                                 return $bucket;
 501                         }
 502                 }
 503
 504                 // Image is bigger than any available bucket
 505                 return false;
 506         }
 507
 508         /**
 509          * Returns ID or name of user who uploaded the file
 510          * STUB
 511          *
 512          * @param string $type 'text' or 'id'
 513          * @return string|int
 514          */
 515         public function getUser( $type = 'text' ) {
 516                 return null;
 517         }
 518
 519         /**
 520          * Get the duration of a media file in seconds
 521          *
 522          * @return int
 523          */
 524         public function getLength() {
 525                 $handler = $this->getHandler();
 526                 if ( $handler ) {
 527                         return $handler->getLength( $this );
 528                 } else {
 529                         return 0;
 530                 }
 531         }
 532
 533         /**
 534          * Return true if the file is vectorized
 535          *
 536          * @return bool
 537          */
 538         public function isVectorized() {
 539                 $handler = $this->getHandler();
 540                 if ( $handler ) {
 541                         return $handler->isVectorized( $this );
 542                 } else {
 543                         return false;
 544                 }
 545         }
 546
 547         /**
 548          * Gives a (possibly empty) list of languages to render
 549          * the file in.
 550          *
 551          * If the file doesn't have translations, or if the file
 552          * format does not support that sort of thing, returns
 553          * an empty array.
 554          *
 555          * @return array
 556          * @since 1.23
 557          */
 558         public function getAvailableLanguages() {
 559                 $handler = $this->getHandler();
 560                 if ( $handler ) {
 561                         return $handler->getAvailableLanguages( $this );
 562                 } else {
 563                         return array();
 564                 }
 565         }
 566
 567         /**
 568          * In files that support multiple language, what is the default language
 569          * to use if none specified.
 570          *
 571          * @return string Lang code, or null if filetype doesn't support multiple languages.
 572          * @since 1.23
 573          */
 574         public function getDefaultRenderLanguage() {
 575                 $handler = $this->getHandler();
 576                 if ( $handler ) {
 577                         return $handler->getDefaultRenderLanguage( $this );
 578                 } else {
 579                         return null;
 580                 }
 581         }
 582
 583         /**
 584          * Will the thumbnail be animated if one would expect it to be.
 585          *
 586          * Currently used to add a warning to the image description page
 587          *
 588          * @return bool False if the main image is both animated
 589          *   and the thumbnail is not. In all other cases must return
 590          *   true. If image is not renderable whatsoever, should
 591          *   return true.
 592          */
 593         public function canAnimateThumbIfAppropriate() {
 594                 $handler = $this->getHandler();
 595                 if ( !$handler ) {
 596                         // We cannot handle image whatsoever, thus
 597                         // one would not expect it to be animated
 598                         // so true.
 599                         return true;
 600                 } else {
 601                         if ( $this->allowInlineDisplay()
 602                                 && $handler->isAnimatedImage( $this )
 603                                 && !$handler->canAnimateThumbnail( $this )
 604                         ) {
 605                                 // Image is animated, but thumbnail isn't.
 606                                 // This is unexpected to the user.
 607                                 return false;
 608                         } else {
 609                                 // Image is not animated, so one would
 610                                 // not expect thumb to be
 611                                 return true;
 612                         }
 613                 }
 614         }
 615
 616         /**
 617          * Get handler-specific metadata
 618          * Overridden by LocalFile, UnregisteredLocalFile
 619          * STUB
 620          * @return bool|array
 621          */
 622         public function getMetadata() {
 623                 return false;
 624         }
 625
 626         /**
 627          * Like getMetadata but returns a handler independent array of common values.
 628          * @see MediaHandler::getCommonMetaArray()
 629          * @return array|bool Array or false if not supported
 630          * @since 1.23
 631          */
 632         public function getCommonMetaArray() {
 633                 $handler = $this->getHandler();
 634
 635                 if ( !$handler ) {
 636                         return false;
 637                 }
 638
 639                 return $handler->getCommonMetaArray( $this );
 640         }
 641
 642         /**
 643          * get versioned metadata
 644          *
 645          * @param array|string $metadata Array or string of (serialized) metadata
 646          * @param int $version Version number.
 647          * @return array Array containing metadata, or what was passed to it on fail
 648          *   (unserializing if not array)
 649          */
 650         public function convertMetadataVersion( $metadata, $version ) {
 651                 $handler = $this->getHandler();
 652                 if ( !is_array( $metadata ) ) {
 653                         // Just to make the return type consistent
 654                         $metadata = unserialize( $metadata );
 655                 }
 656                 if ( $handler ) {
 657                         return $handler->convertMetadataVersion( $metadata, $version );
 658                 } else {
 659                         return $metadata;
 660                 }
 661         }
 662
 663         /**
 664          * Return the bit depth of the file
 665          * Overridden by LocalFile
 666          * STUB
 667          * @return int
 668          */
 669         public function getBitDepth() {
 670                 return 0;
 671         }
 672
 673         /**
 674          * Return the size of the image file, in bytes
 675          * Overridden by LocalFile, UnregisteredLocalFile
 676          * STUB
 677          * @return bool
 678          */
 679         public function getSize() {
 680                 return false;
 681         }
 682
 683         /**
 684          * Returns the MIME type of the file.
 685          * Overridden by LocalFile, UnregisteredLocalFile
 686          * STUB
 687          *
 688          * @return string
 689          */
 690         function getMimeType() {
 691                 return 'unknown/unknown';
 692         }
 693
 694         /**
 695          * Return the type of the media in the file.
 696          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 697          * Overridden by LocalFile,
 698          * STUB
 699          * @return string
 700          */
 701         function getMediaType() {
 702                 return MEDIATYPE_UNKNOWN;
 703         }
 704
 705         /**
 706          * Checks if the output of transform() for this file is likely
 707          * to be valid. If this is false, various user elements will
 708          * display a placeholder instead.
 709          *
 710          * Currently, this checks if the file is an image format
 711          * that can be converted to a format
 712          * supported by all browsers (namely GIF, PNG and JPEG),
 713          * or if it is an SVG image and SVG conversion is enabled.
 714          *
 715          * @return bool
 716          */
 717         function canRender() {
 718                 if ( !isset( $this->canRender ) ) {
 719                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this ) && $this->exists();
 720                 }
 721
 722                 return $this->canRender;
 723         }
 724
 725         /**
 726          * Accessor for __get()
 727          * @return bool
 728          */
 729         protected function getCanRender() {
 730                 return $this->canRender();
 731         }
 732
 733         /**
 734          * Return true if the file is of a type that can't be directly
 735          * rendered by typical browsers and needs to be re-rasterized.
 736          *
 737          * This returns true for everything but the bitmap types
 738          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 739          * also return true for any non-image formats.
 740          *
 741          * @return bool
 742          */
 743         function mustRender() {
 744                 return $this->getHandler() && $this->handler->mustRender( $this );
 745         }
 746
 747         /**
 748          * Alias for canRender()
 749          *
 750          * @return bool
 751          */
 752         function allowInlineDisplay() {
 753                 return $this->canRender();
 754         }
 755
 756         /**
 757          * Determines if this media file is in a format that is unlikely to
 758          * contain viruses or malicious content. It uses the global
 759          * $wgTrustedMediaFormats list to determine if the file is safe.
 760          *
 761          * This is used to show a warning on the description page of non-safe files.
 762          * It may also be used to disallow direct [[media:...]] links to such files.
 763          *
 764          * Note that this function will always return true if allowInlineDisplay()
 765          * or isTrustedFile() is true for this file.
 766          *
 767          * @return bool
 768          */
 769         function isSafeFile() {
 770                 if ( !isset( $this->isSafeFile ) ) {
 771                         $this->isSafeFile = $this->getIsSafeFileUncached();
 772                 }
 773
 774                 return $this->isSafeFile;
 775         }
 776
 777         /**
 778          * Accessor for __get()
 779          *
 780          * @return bool
 781          */
 782         protected function getIsSafeFile() {
 783                 return $this->isSafeFile();
 784         }
 785
 786         /**
 787          * Uncached accessor
 788          *
 789          * @return bool
 790          */
 791         protected function getIsSafeFileUncached() {
 792                 global $wgTrustedMediaFormats;
 793
 794                 if ( $this->allowInlineDisplay() ) {
 795                         return true;
 796                 }
 797                 if ( $this->isTrustedFile() ) {
 798                         return true;
 799                 }
 800
 801                 $type = $this->getMediaType();
 802                 $mime = $this->getMimeType();
 803                 #wfDebug( "LocalFile::isSafeFile: type= $type, mime= $mime\n" );
 804
 805                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 806                         return false; #unknown type, not trusted
 807                 }
 808                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 809                         return true;
 810                 }
 811
 812                 if ( $mime === "unknown/unknown" ) {
 813                         return false; #unknown type, not trusted
 814                 }
 815                 if ( in_array( $mime, $wgTrustedMediaFormats ) ) {
 816                         return true;
 817                 }
 818
 819                 return false;
 820         }
 821
 822         /**
 823          * Returns true if the file is flagged as trusted. Files flagged that way
 824          * can be linked to directly, even if that is not allowed for this type of
 825          * file normally.
 826          *
 827          * This is a dummy function right now and always returns false. It could be
 828          * implemented to extract a flag from the database. The trusted flag could be
 829          * set on upload, if the user has sufficient privileges, to bypass script-
 830          * and html-filters. It may even be coupled with cryptographics signatures
 831          * or such.
 832          *
 833          * @return bool
 834          */
 835         function isTrustedFile() {
 836                 #this could be implemented to check a flag in the database,
 837                 #look for signatures, etc
 838                 return false;
 839         }
 840
 841         /**
 842          * Returns true if file exists in the repository.
 843          *
 844          * Overridden by LocalFile to avoid unnecessary stat calls.
 845          *
 846          * @return bool Whether file exists in the repository.
 847          */
 848         public function exists() {
 849                 return $this->getPath() && $this->repo->fileExists( $this->path );
 850         }
 851
 852         /**
 853          * Returns true if file exists in the repository and can be included in a page.
 854          * It would be unsafe to include private images, making public thumbnails inadvertently
 855          *
 856          * @return bool Whether file exists in the repository and is includable.
 857          */
 858         public function isVisible() {
 859                 return $this->exists();
 860         }
 861
 862         /**
 863          * @return string
 864          */
 865         function getTransformScript() {
 866                 if ( !isset( $this->transformScript ) ) {
 867                         $this->transformScript = false;
 868                         if ( $this->repo ) {
 869                                 $script = $this->repo->getThumbScriptUrl();
 870                                 if ( $script ) {
 871                                         $this->transformScript = wfAppendQuery( $script, array( 'f' => $this->getName() ) );
 872                                 }
 873                         }
 874                 }
 875
 876                 return $this->transformScript;
 877         }
 878
 879         /**
 880          * Get a ThumbnailImage which is the same size as the source
 881          *
 882          * @param array $handlerParams
 883          *
 884          * @return string
 885          */
 886         function getUnscaledThumb( $handlerParams = array() ) {
 887                 $hp =& $handlerParams;
 888                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 889                 $width = $this->getWidth( $page );
 890                 if ( !$width ) {
 891                         return $this->iconThumb();
 892                 }
 893                 $hp['width'] = $width;
 894                 // be sure to ignore any height specification as well (bug 62258)
 895                 unset( $hp['height'] );
 896
 897                 return $this->transform( $hp );
 898         }
 899
 900         /**
 901          * Return the file name of a thumbnail with the specified parameters.
 902          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 903          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 904          *
 905          * @param array $params Handler-specific parameters
 906          * @param int $flags Bitfield that supports THUMB_* constants
 907          * @return string
 908          */
 909         public function thumbName( $params, $flags = 0 ) {
 910                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 911                         ? $this->repo->nameForThumb( $this->getName() )
 912                         : $this->getName();
 913
 914                 return $this->generateThumbName( $name, $params );
 915         }
 916
 917         /**
 918          * Generate a thumbnail file name from a name and specified parameters
 919          *
 920          * @param string $name
 921          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 922          * @return string
 923          */
 924         public function generateThumbName( $name, $params ) {
 925                 if ( !$this->getHandler() ) {
 926                         return null;
 927                 }
 928                 $extension = $this->getExtension();
 929                 list( $thumbExt, ) = $this->getHandler()->getThumbType(
 930                         $extension, $this->getMimeType(), $params );
 931                 $thumbName = $this->getHandler()->makeParamString( $params ) . '-' . $name;
 932                 if ( $thumbExt != $extension ) {
 933                         $thumbName .= ".$thumbExt";
 934                 }
 935
 936                 return $thumbName;
 937         }
 938
 939         /**
 940          * Create a thumbnail of the image having the specified width/height.
 941          * The thumbnail will not be created if the width is larger than the
 942          * image's width. Let the browser do the scaling in this case.
 943          * The thumbnail is stored on disk and is only computed if the thumbnail
 944          * file does not exist OR if it is older than the image.
 945          * Returns the URL.
 946          *
 947          * Keeps aspect ratio of original image. If both width and height are
 948          * specified, the generated image will be no bigger than width x height,
 949          * and will also have correct aspect ratio.
 950          *
 951          * @param int $width Maximum width of the generated thumbnail
 952          * @param int $height Maximum height of the image (optional)
 953          *
 954          * @return string
 955          */
 956         public function createThumb( $width, $height = -1 ) {
 957                 $params = array( 'width' => $width );
 958                 if ( $height != -1 ) {
 959                         $params['height'] = $height;
 960                 }
 961                 $thumb = $this->transform( $params );
 962                 if ( !$thumb || $thumb->isError() ) {
 963                         return '';
 964                 }
 965
 966                 return $thumb->getUrl();
 967         }
 968
 969         /**
 970          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 971          *
 972          * @param string $thumbPath Thumbnail storage path
 973          * @param string $thumbUrl Thumbnail URL
 974          * @param array $params
 975          * @param int $flags
 976          * @return MediaTransformOutput
 977          */
 978         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 979                 global $wgIgnoreImageErrors;
 980
 981                 $handler = $this->getHandler();
 982                 if ( $handler && $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 983                         return $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 984                 } else {
 985                         return new MediaTransformError( 'thumbnail_error',
 986                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 987                 }
 988         }
 989
 990         /**
 991          * Transform a media file
 992          *
 993          * @param array $params An associative array of handler-specific parameters.
 994          *   Typical keys are width, height and page.
 995          * @param int $flags A bitfield, may contain self::RENDER_NOW to force rendering
 996          * @return MediaTransformOutput|bool False on failure
 997          */
 998         function transform( $params, $flags = 0 ) {
 999                 global $wgThumbnailEpoch;
1000
1001                 wfProfileIn( __METHOD__ );
1002                 do {
1003                         if ( !$this->canRender() ) {
1004                                 $thumb = $this->iconThumb();
1005                                 break; // not a bitmap or renderable image, don't try
1006                         }
1007
1008                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
1009                         $descriptionUrl = $this->getDescriptionUrl();
1010                         if ( $descriptionUrl ) {
1011                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
1012                         }
1013
1014                         $handler = $this->getHandler();
1015                         $script = $this->getTransformScript();
1016                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
1017                                 // Use a script to transform on client request, if possible
1018                                 $thumb = $handler->getScriptedTransform( $this, $script, $params );
1019                                 if ( $thumb ) {
1020                                         break;
1021                                 }
1022                         }
1023
1024                         $normalisedParams = $params;
1025                         $handler->normaliseParams( $this, $normalisedParams );
1026
1027                         $thumbName = $this->thumbName( $normalisedParams );
1028                         $thumbUrl = $this->getThumbUrl( $thumbName );
1029                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1030
1031                         if ( $this->repo ) {
1032                                 // Defer rendering if a 404 handler is set up...
1033                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
1034                                         wfDebug( __METHOD__ . " transformation deferred.\n" );
1035                                         // XXX: Pass in the storage path even though we are not rendering anything
1036                                         // and the path is supposed to be an FS path. This is due to getScalerType()
1037                                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
1038                                         $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
1039                                         break;
1040                                 }
1041                                 // Check if an up-to-date thumbnail already exists...
1042                                 wfDebug( __METHOD__ . ": Doing stat for $thumbPath\n" );
1043                                 if ( !( $flags & self::RENDER_FORCE ) && $this->repo->fileExists( $thumbPath ) ) {
1044                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
1045                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
1046                                                 // XXX: Pass in the storage path even though we are not rendering anything
1047                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
1048                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
1049                                                 $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
1050                                                 $thumb->setStoragePath( $thumbPath );
1051                                                 break;
1052                                         }
1053                                 } elseif ( $flags & self::RENDER_FORCE ) {
1054                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
1055                                 }
1056
1057                                 // If the backend is ready-only, don't keep generating thumbnails
1058                                 // only to return transformation errors, just return the error now.
1059                                 if ( $this->repo->getReadOnlyReason() !== false ) {
1060                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1061                                         break;
1062                                 }
1063                         }
1064
1065                         $tmpFile = $this->makeTransformTmpFile( $thumbPath );
1066
1067                         if ( !$tmpFile ) {
1068                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1069                         } else {
1070                                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1071                         }
1072                 } while ( false );
1073
1074                 wfProfileOut( __METHOD__ );
1075
1076                 return is_object( $thumb ) ? $thumb : false;
1077         }
1078
1079         /**
1080          * Generates a thumbnail according to the given parameters and saves it to storage
1081          * @param TempFSFile $tmpFile Temporary file where the rendered thumbnail will be saved
1082          * @param array $transformParams
1083          * @param int $flags
1084          * @return bool|MediaTransformOutput
1085          */
1086         public function generateAndSaveThumb( $tmpFile, $transformParams, $flags ) {
1087                 global $wgUseSquid, $wgIgnoreImageErrors;
1088
1089                 $handler = $this->getHandler();
1090
1091                 $normalisedParams = $transformParams;
1092                 $handler->normaliseParams( $this, $normalisedParams );
1093
1094                 $thumbName = $this->thumbName( $normalisedParams );
1095                 $thumbUrl = $this->getThumbUrl( $thumbName );
1096                 $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1097
1098                 $tmpThumbPath = $tmpFile->getPath();
1099
1100                 if ( $handler->supportsBucketing() ) {
1101                         $this->generateBucketsIfNeeded( $normalisedParams, $flags );
1102                 }
1103
1104                 // Actually render the thumbnail...
1105                 wfProfileIn( __METHOD__ . '-doTransform' );
1106                 $thumb = $handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1107                 wfProfileOut( __METHOD__ . '-doTransform' );
1108                 $tmpFile->bind( $thumb ); // keep alive with $thumb
1109
1110                 if ( !$thumb ) { // bad params?
1111                         $thumb = false;
1112                 } elseif ( $thumb->isError() ) { // transform error
1113                         $this->lastError = $thumb->toText();
1114                         // Ignore errors if requested
1115                         if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
1116                                 $thumb = $handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1117                         }
1118                 } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
1119                         // Copy the thumbnail from the file system into storage...
1120                         $disposition = $this->getThumbDisposition( $thumbName );
1121                         $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
1122                         if ( $status->isOK() ) {
1123                                 $thumb->setStoragePath( $thumbPath );
1124                         } else {
1125                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $transformParams, $flags );
1126                         }
1127                         // Give extensions a chance to do something with this thumbnail...
1128                         Hooks::run( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
1129                 }
1130
1131                 // Purge. Useful in the event of Core -> Squid connection failure or squid
1132                 // purge collisions from elsewhere during failure. Don't keep triggering for
1133                 // "thumbs" which have the main image URL though (bug 13776)
1134                 if ( $wgUseSquid ) {
1135                         if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
1136                                 SquidUpdate::purge( array( $thumbUrl ) );
1137                         }
1138                 }
1139
1140                 return $thumb;
1141         }
1142
1143         /**
1144          * Generates chained bucketed thumbnails if needed
1145          * @param array $params
1146          * @param int $flags
1147          * @return bool Whether at least one bucket was generated
1148          */
1149         protected function generateBucketsIfNeeded( $params, $flags = 0 ) {
1150                 if ( !$this->repo
1151                         || !isset( $params['physicalWidth'] )
1152                         || !isset( $params['physicalHeight'] )
1153                         || !( $bucket = $this->getThumbnailBucket( $params['physicalWidth'] ) )
1154                         || $bucket == $params['physicalWidth'] ) {
1155                         return false;
1156                 }
1157
1158                 $bucketPath = $this->getBucketThumbPath( $bucket );
1159
1160                 if ( $this->repo->fileExists( $bucketPath ) ) {
1161                         return false;
1162                 }
1163
1164                 $params['physicalWidth'] = $bucket;
1165                 $params['width'] = $bucket;
1166
1167                 $params = $this->getHandler()->sanitizeParamsForBucketing( $params );
1168
1169                 $bucketName = $this->getBucketThumbName( $bucket );
1170
1171                 $tmpFile = $this->makeTransformTmpFile( $bucketPath );
1172
1173                 if ( !$tmpFile ) {
1174                         return false;
1175                 }
1176
1177                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1178
1179                 if ( !$thumb || $thumb->isError() ) {
1180                         return false;
1181                 }
1182
1183                 $this->tmpBucketedThumbCache[$bucket] = $tmpFile->getPath();
1184                 // For the caching to work, we need to make the tmp file survive as long as
1185                 // this object exists
1186                 $tmpFile->bind( $this );
1187
1188                 return true;
1189         }
1190
1191         /**
1192          * Returns the most appropriate source image for the thumbnail, given a target thumbnail size
1193          * @param array $params
1194          * @return array Source path and width/height of the source
1195          */
1196         public function getThumbnailSource( $params ) {
1197                 if ( $this->repo
1198                         && $this->getHandler()->supportsBucketing()
1199                         && isset( $params['physicalWidth'] )
1200                         && $bucket = $this->getThumbnailBucket( $params['physicalWidth'] )
1201                 ) {
1202                         if ( $this->getWidth() != 0 ) {
1203                                 $bucketHeight = round( $this->getHeight() * ( $bucket / $this->getWidth() ) );
1204                         } else {
1205                                 $bucketHeight = 0;
1206                         }
1207
1208                         // Try to avoid reading from storage if the file was generated by this script
1209                         if ( isset( $this->tmpBucketedThumbCache[$bucket] ) ) {
1210                                 $tmpPath = $this->tmpBucketedThumbCache[$bucket];
1211
1212                                 if ( file_exists( $tmpPath ) ) {
1213                                         return array(
1214                                                 'path' => $tmpPath,
1215                                                 'width' => $bucket,
1216                                                 'height' => $bucketHeight
1217                                         );
1218                                 }
1219                         }
1220
1221                         $bucketPath = $this->getBucketThumbPath( $bucket );
1222
1223                         if ( $this->repo->fileExists( $bucketPath ) ) {
1224                                 $fsFile = $this->repo->getLocalReference( $bucketPath );
1225
1226                                 if ( $fsFile ) {
1227                                         return array(
1228                                                 'path' => $fsFile->getPath(),
1229                                                 'width' => $bucket,
1230                                                 'height' => $bucketHeight
1231                                         );
1232                                 }
1233                         }
1234                 }
1235
1236                 // Thumbnailing a very large file could result in network saturation if
1237                 // everyone does it at once.
1238                 if ( $this->getSize() >= 1e7 ) { // 10MB
1239                         $that = $this;
1240                         $work = new PoolCounterWorkViaCallback( 'GetLocalFileCopy', sha1( $this->getName() ),
1241                                 array(
1242                                         'doWork' => function () use ( $that ) {
1243                                                 return $that->getLocalRefPath();
1244                                         }
1245                                 )
1246                         );
1247                         $srcPath = $work->execute();
1248                 } else {
1249                         $srcPath = $this->getLocalRefPath();
1250                 }
1251
1252                 // Original file
1253                 return array(
1254                         'path' => $srcPath,
1255                         'width' => $this->getWidth(),
1256                         'height' => $this->getHeight()
1257                 );
1258         }
1259
1260         /**
1261          * Returns the repo path of the thumb for a given bucket
1262          * @param int $bucket
1263          * @return string
1264          */
1265         protected function getBucketThumbPath( $bucket ) {
1266                 $thumbName = $this->getBucketThumbName( $bucket );
1267                 return $this->getThumbPath( $thumbName );
1268         }
1269
1270         /**
1271          * Returns the name of the thumb for a given bucket
1272          * @param int $bucket
1273          * @return string
1274          */
1275         protected function getBucketThumbName( $bucket ) {
1276                 return $this->thumbName( array( 'physicalWidth' => $bucket ) );
1277         }
1278
1279         /**
1280          * Creates a temp FS file with the same extension and the thumbnail
1281          * @param string $thumbPath Thumbnail path
1282          * @return TempFSFile
1283          */
1284         protected function makeTransformTmpFile( $thumbPath ) {
1285                 $thumbExt = FileBackend::extensionFromPath( $thumbPath );
1286                 return TempFSFile::factory( 'transform_', $thumbExt );
1287         }
1288
1289         /**
1290          * @param string $thumbName Thumbnail name
1291          * @param string $dispositionType Type of disposition (either "attachment" or "inline")
1292          * @return string Content-Disposition header value
1293          */
1294         function getThumbDisposition( $thumbName, $dispositionType = 'inline' ) {
1295                 $fileName = $this->name; // file name to suggest
1296                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
1297                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
1298                         $fileName .= ".$thumbExt";
1299                 }
1300
1301                 return FileBackend::makeContentDisposition( $dispositionType, $fileName );
1302         }
1303
1304         /**
1305          * Hook into transform() to allow migration of thumbnail files
1306          * STUB
1307          * Overridden by LocalFile
1308          * @param string $thumbName
1309          */
1310         function migrateThumbFile( $thumbName ) {
1311         }
1312
1313         /**
1314          * Get a MediaHandler instance for this file
1315          *
1316          * @return MediaHandler|bool Registered MediaHandler for file's MIME type
1317          *   or false if none found
1318          */
1319         function getHandler() {
1320                 if ( !isset( $this->handler ) ) {
1321                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1322                 }
1323
1324                 return $this->handler;
1325         }
1326
1327         /**
1328          * Get a ThumbnailImage representing a file type icon
1329          *
1330          * @return ThumbnailImage
1331          */
1332         function iconThumb() {
1333                 global $wgResourceBasePath, $IP;
1334                 $assetsPath = "$wgResourceBasePath/resources/assets/file-type-icons/";
1335                 $assetsDirectory = "$IP/resources/assets/file-type-icons/";
1336
1337                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1338                 foreach ( $try as $icon ) {
1339                         if ( file_exists( $assetsDirectory . $icon ) ) { // always FS
1340                                 $params = array( 'width' => 120, 'height' => 120 );
1341
1342                                 return new ThumbnailImage( $this, $assetsPath . $icon, false, $params );
1343                         }
1344                 }
1345
1346                 return null;
1347         }
1348
1349         /**
1350          * Get last thumbnailing error.
1351          * Largely obsolete.
1352          * @return string
1353          */
1354         function getLastError() {
1355                 return $this->lastError;
1356         }
1357
1358         /**
1359          * Get all thumbnail names previously generated for this file
1360          * STUB
1361          * Overridden by LocalFile
1362          * @return array
1363          */
1364         function getThumbnails() {
1365                 return array();
1366         }
1367
1368         /**
1369          * Purge shared caches such as thumbnails and DB data caching
1370          * STUB
1371          * Overridden by LocalFile
1372          * @param array $options Options, which include:
1373          *   'forThumbRefresh' : The purging is only to refresh thumbnails
1374          */
1375         function purgeCache( $options = array() ) {
1376         }
1377
1378         /**
1379          * Purge the file description page, but don't go after
1380          * pages using the file. Use when modifying file history
1381          * but not the current data.
1382          */
1383         function purgeDescription() {
1384                 $title = $this->getTitle();
1385                 if ( $title ) {
1386                         $title->invalidateCache();
1387                         $title->purgeSquid();
1388                 }
1389         }
1390
1391         /**
1392          * Purge metadata and all affected pages when the file is created,
1393          * deleted, or majorly updated.
1394          */
1395         function purgeEverything() {
1396                 // Delete thumbnails and refresh file metadata cache
1397                 $this->purgeCache();
1398                 $this->purgeDescription();
1399
1400                 // Purge cache of all pages using this file
1401                 $title = $this->getTitle();
1402                 if ( $title ) {
1403                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1404                         $update->doUpdate();
1405                 }
1406         }
1407
1408         /**
1409          * Return a fragment of the history of file.
1410          *
1411          * STUB
1412          * @param int $limit Limit of rows to return
1413          * @param string $start Only revisions older than $start will be returned
1414          * @param string $end Only revisions newer than $end will be returned
1415          * @param bool $inc Include the endpoints of the time range
1416          *
1417          * @return array
1418          */
1419         function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
1420                 return array();
1421         }
1422
1423         /**
1424          * Return the history of this file, line by line. Starts with current version,
1425          * then old versions. Should return an object similar to an image/oldimage
1426          * database row.
1427          *
1428          * STUB
1429          * Overridden in LocalFile
1430          * @return bool
1431          */
1432         public function nextHistoryLine() {
1433                 return false;
1434         }
1435
1436         /**
1437          * Reset the history pointer to the first element of the history.
1438          * Always call this function after using nextHistoryLine() to free db resources
1439          * STUB
1440          * Overridden in LocalFile.
1441          */
1442         public function resetHistory() {
1443         }
1444
1445         /**
1446          * Get the filename hash component of the directory including trailing slash,
1447          * e.g. f/fa/
1448          * If the repository is not hashed, returns an empty string.
1449          *
1450          * @return string
1451          */
1452         function getHashPath() {
1453                 if ( !isset( $this->hashPath ) ) {
1454                         $this->assertRepoDefined();
1455                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1456                 }
1457
1458                 return $this->hashPath;
1459         }
1460
1461         /**
1462          * Get the path of the file relative to the public zone root.
1463          * This function is overridden in OldLocalFile to be like getArchiveRel().
1464          *
1465          * @return string
1466          */
1467         function getRel() {
1468                 return $this->getHashPath() . $this->getName();
1469         }
1470
1471         /**
1472          * Get the path of an archived file relative to the public zone root
1473          *
1474          * @param bool|string $suffix If not false, the name of an archived thumbnail file
1475          *
1476          * @return string
1477          */
1478         function getArchiveRel( $suffix = false ) {
1479                 $path = 'archive/' . $this->getHashPath();
1480                 if ( $suffix === false ) {
1481                         $path = substr( $path, 0, -1 );
1482                 } else {
1483                         $path .= $suffix;
1484                 }
1485
1486                 return $path;
1487         }
1488
1489         /**
1490          * Get the path, relative to the thumbnail zone root, of the
1491          * thumbnail directory or a particular file if $suffix is specified
1492          *
1493          * @param bool|string $suffix If not false, the name of a thumbnail file
1494          * @return string
1495          */
1496         function getThumbRel( $suffix = false ) {
1497                 $path = $this->getRel();
1498                 if ( $suffix !== false ) {
1499                         $path .= '/' . $suffix;
1500                 }
1501
1502                 return $path;
1503         }
1504
1505         /**
1506          * Get urlencoded path of the file relative to the public zone root.
1507          * This function is overridden in OldLocalFile to be like getArchiveUrl().
1508          *
1509          * @return string
1510          */
1511         function getUrlRel() {
1512                 return $this->getHashPath() . rawurlencode( $this->getName() );
1513         }
1514
1515         /**
1516          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1517          * or a specific thumb if the $suffix is given.
1518          *
1519          * @param string $archiveName The timestamped name of an archived image
1520          * @param bool|string $suffix If not false, the name of a thumbnail file
1521          * @return string
1522          */
1523         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1524                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1525                 if ( $suffix === false ) {
1526                         $path = substr( $path, 0, -1 );
1527                 } else {
1528                         $path .= $suffix;
1529                 }
1530
1531                 return $path;
1532         }
1533
1534         /**
1535          * Get the path of the archived file.
1536          *
1537          * @param bool|string $suffix If not false, the name of an archived file.
1538          * @return string
1539          */
1540         function getArchivePath( $suffix = false ) {
1541                 $this->assertRepoDefined();
1542
1543                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1544         }
1545
1546         /**
1547          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1548          *
1549          * @param string $archiveName The timestamped name of an archived image
1550          * @param bool|string $suffix If not false, the name of a thumbnail file
1551          * @return string
1552          */
1553         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1554                 $this->assertRepoDefined();
1555
1556                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1557                 $this->getArchiveThumbRel( $archiveName, $suffix );
1558         }
1559
1560         /**
1561          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1562          *
1563          * @param bool|string $suffix If not false, the name of a thumbnail file
1564          * @return string
1565          */
1566         function getThumbPath( $suffix = false ) {
1567                 $this->assertRepoDefined();
1568
1569                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1570         }
1571
1572         /**
1573          * Get the path of the transcoded directory, or a particular file if $suffix is specified
1574          *
1575          * @param bool|string $suffix If not false, the name of a media file
1576          * @return string
1577          */
1578         function getTranscodedPath( $suffix = false ) {
1579                 $this->assertRepoDefined();
1580
1581                 return $this->repo->getZonePath( 'transcoded' ) . '/' . $this->getThumbRel( $suffix );
1582         }
1583
1584         /**
1585          * Get the URL of the archive directory, or a particular file if $suffix is specified
1586          *
1587          * @param bool|string $suffix If not false, the name of an archived file
1588          * @return string
1589          */
1590         function getArchiveUrl( $suffix = false ) {
1591                 $this->assertRepoDefined();
1592                 $ext = $this->getExtension();
1593                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1594                 if ( $suffix === false ) {
1595                         $path = substr( $path, 0, -1 );
1596                 } else {
1597                         $path .= rawurlencode( $suffix );
1598                 }
1599
1600                 return $path;
1601         }
1602
1603         /**
1604          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1605          *
1606          * @param string $archiveName The timestamped name of an archived image
1607          * @param bool|string $suffix If not false, the name of a thumbnail file
1608          * @return string
1609          */
1610         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1611                 $this->assertRepoDefined();
1612                 $ext = $this->getExtension();
1613                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1614                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1615                 if ( $suffix === false ) {
1616                         $path = substr( $path, 0, -1 );
1617                 } else {
1618                         $path .= rawurlencode( $suffix );
1619                 }
1620
1621                 return $path;
1622         }
1623
1624         /**
1625          * Get the URL of the zone directory, or a particular file if $suffix is specified
1626          *
1627          * @param string $zone Name of requested zone
1628          * @param bool|string $suffix If not false, the name of a file in zone
1629          * @return string Path
1630          */
1631         function getZoneUrl( $zone, $suffix = false ) {
1632                 $this->assertRepoDefined();
1633                 $ext = $this->getExtension();
1634                 $path = $this->repo->getZoneUrl( $zone, $ext ) . '/' . $this->getUrlRel();
1635                 if ( $suffix !== false ) {
1636                         $path .= '/' . rawurlencode( $suffix );
1637                 }
1638
1639                 return $path;
1640         }
1641
1642         /**
1643          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1644          *
1645          * @param bool|string $suffix If not false, the name of a thumbnail file
1646          * @return string Path
1647          */
1648         function getThumbUrl( $suffix = false ) {
1649                 return $this->getZoneUrl( 'thumb', $suffix );
1650         }
1651
1652         /**
1653          * Get the URL of the transcoded directory, or a particular file if $suffix is specified
1654          *
1655          * @param bool|string $suffix If not false, the name of a media file
1656          * @return string Path
1657          */
1658         function getTranscodedUrl( $suffix = false ) {
1659                 return $this->getZoneUrl( 'transcoded', $suffix );
1660         }
1661
1662         /**
1663          * Get the public zone virtual URL for a current version source file
1664          *
1665          * @param bool|string $suffix If not false, the name of a thumbnail file
1666          * @return string
1667          */
1668         function getVirtualUrl( $suffix = false ) {
1669                 $this->assertRepoDefined();
1670                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1671                 if ( $suffix !== false ) {
1672                         $path .= '/' . rawurlencode( $suffix );
1673                 }
1674
1675                 return $path;
1676         }
1677
1678         /**
1679          * Get the public zone virtual URL for an archived version source file
1680          *
1681          * @param bool|string $suffix If not false, the name of a thumbnail file
1682          * @return string
1683          */
1684         function getArchiveVirtualUrl( $suffix = false ) {
1685                 $this->assertRepoDefined();
1686                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1687                 if ( $suffix === false ) {
1688                         $path = substr( $path, 0, -1 );
1689                 } else {
1690                         $path .= rawurlencode( $suffix );
1691                 }
1692
1693                 return $path;
1694         }
1695
1696         /**
1697          * Get the virtual URL for a thumbnail file or directory
1698          *
1699          * @param bool|string $suffix If not false, the name of a thumbnail file
1700          * @return string
1701          */
1702         function getThumbVirtualUrl( $suffix = false ) {
1703                 $this->assertRepoDefined();
1704                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1705                 if ( $suffix !== false ) {
1706                         $path .= '/' . rawurlencode( $suffix );
1707                 }
1708
1709                 return $path;
1710         }
1711
1712         /**
1713          * @return bool
1714          */
1715         function isHashed() {
1716                 $this->assertRepoDefined();
1717
1718                 return (bool)$this->repo->getHashLevels();
1719         }
1720
1721         /**
1722          * @throws MWException
1723          */
1724         function readOnlyError() {
1725                 throw new MWException( get_class( $this ) . ': write operations are not supported' );
1726         }
1727
1728         /**
1729          * Record a file upload in the upload log and the image table
1730          * STUB
1731          * Overridden by LocalFile
1732          * @param string $oldver
1733          * @param string $desc
1734          * @param string $license
1735          * @param string $copyStatus
1736          * @param string $source
1737          * @param bool $watch
1738          * @param string|bool $timestamp
1739          * @param null|User $user User object or null to use $wgUser
1740          * @return bool
1741          * @throws MWException
1742          */
1743         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
1744                 $watch = false, $timestamp = false, User $user = null
1745         ) {
1746                 $this->readOnlyError();
1747         }
1748
1749         /**
1750          * Move or copy a file to its public location. If a file exists at the
1751          * destination, move it to an archive. Returns a FileRepoStatus object with
1752          * the archive name in the "value" member on success.
1753          *
1754          * The archive name should be passed through to recordUpload for database
1755          * registration.
1756          *
1757          * Options to $options include:
1758          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1759          *
1760          * @param string $srcPath Local filesystem path to the source image
1761          * @param int $flags A bitwise combination of:
1762          *   File::DELETE_SOURCE    Delete the source file, i.e. move rather than copy
1763          * @param array $options Optional additional parameters
1764          * @return FileRepoStatus On success, the value member contains the
1765          *   archive name, or an empty string if it was a new file.
1766          *
1767          * STUB
1768          * Overridden by LocalFile
1769          */
1770         function publish( $srcPath, $flags = 0, array $options = array() ) {
1771                 $this->readOnlyError();
1772         }
1773
1774         /**
1775          * @return bool
1776          */
1777         function formatMetadata() {
1778                 if ( !$this->getHandler() ) {
1779                         return false;
1780                 }
1781
1782                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1783         }
1784
1785         /**
1786          * Returns true if the file comes from the local file repository.
1787          *
1788          * @return bool
1789          */
1790         function isLocal() {
1791                 return $this->repo && $this->repo->isLocal();
1792         }
1793
1794         /**
1795          * Returns the name of the repository.
1796          *
1797          * @return string
1798          */
1799         function getRepoName() {
1800                 return $this->repo ? $this->repo->getName() : 'unknown';
1801         }
1802
1803         /**
1804          * Returns the repository
1805          *
1806          * @return FileRepo|LocalRepo|bool
1807          */
1808         function getRepo() {
1809                 return $this->repo;
1810         }
1811
1812         /**
1813          * Returns true if the image is an old version
1814          * STUB
1815          *
1816          * @return bool
1817          */
1818         function isOld() {
1819                 return false;
1820         }
1821
1822         /**
1823          * Is this file a "deleted" file in a private archive?
1824          * STUB
1825          *
1826          * @param int $field One of DELETED_* bitfield constants
1827          * @return bool
1828          */
1829         function isDeleted( $field ) {
1830                 return false;
1831         }
1832
1833         /**
1834          * Return the deletion bitfield
1835          * STUB
1836          * @return int
1837          */
1838         function getVisibility() {
1839                 return 0;
1840         }
1841
1842         /**
1843          * Was this file ever deleted from the wiki?
1844          *
1845          * @return bool
1846          */
1847         function wasDeleted() {
1848                 $title = $this->getTitle();
1849
1850                 return $title && $title->isDeletedQuick();
1851         }
1852
1853         /**
1854          * Move file to the new title
1855          *
1856          * Move current, old version and all thumbnails
1857          * to the new filename. Old file is deleted.
1858          *
1859          * Cache purging is done; checks for validity
1860          * and logging are caller's responsibility
1861          *
1862          * @param Title $target New file name
1863          * @return FileRepoStatus
1864          */
1865         function move( $target ) {
1866                 $this->readOnlyError();
1867         }
1868
1869         /**
1870          * Delete all versions of the file.
1871          *
1872          * Moves the files into an archive directory (or deletes them)
1873          * and removes the database rows.
1874          *
1875          * Cache purging is done; logging is caller's responsibility.
1876          *
1877          * @param string $reason
1878          * @param bool $suppress Hide content from sysops?
1879          * @param User|null $user
1880          * @return bool Boolean on success, false on some kind of failure
1881          * STUB
1882          * Overridden by LocalFile
1883          */
1884         function delete( $reason, $suppress = false, $user = null ) {
1885                 $this->readOnlyError();
1886         }
1887
1888         /**
1889          * Restore all or specified deleted revisions to the given file.
1890          * Permissions and logging are left to the caller.
1891          *
1892          * May throw database exceptions on error.
1893          *
1894          * @param array $versions Set of record ids of deleted items to restore,
1895          *   or empty to restore all revisions.
1896          * @param bool $unsuppress Remove restrictions on content upon restoration?
1897          * @return int|bool The number of file revisions restored if successful,
1898          *   or false on failure
1899          * STUB
1900          * Overridden by LocalFile
1901          */
1902         function restore( $versions = array(), $unsuppress = false ) {
1903                 $this->readOnlyError();
1904         }
1905
1906         /**
1907          * Returns 'true' if this file is a type which supports multiple pages,
1908          * e.g. DJVU or PDF. Note that this may be true even if the file in
1909          * question only has a single page.
1910          *
1911          * @return bool
1912          */
1913         function isMultipage() {
1914                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1915         }
1916
1917         /**
1918          * Returns the number of pages of a multipage document, or false for
1919          * documents which aren't multipage documents
1920          *
1921          * @return bool|int
1922          */
1923         function pageCount() {
1924                 if ( !isset( $this->pageCount ) ) {
1925                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1926                                 $this->pageCount = $this->handler->pageCount( $this );
1927                         } else {
1928                                 $this->pageCount = false;
1929                         }
1930                 }
1931
1932                 return $this->pageCount;
1933         }
1934
1935         /**
1936          * Calculate the height of a thumbnail using the source and destination width
1937          *
1938          * @param int $srcWidth
1939          * @param int $srcHeight
1940          * @param int $dstWidth
1941          *
1942          * @return int
1943          */
1944         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1945                 // Exact integer multiply followed by division
1946                 if ( $srcWidth == 0 ) {
1947                         return 0;
1948                 } else {
1949                         return round( $srcHeight * $dstWidth / $srcWidth );
1950                 }
1951         }
1952
1953         /**
1954          * Get an image size array like that returned by getImageSize(), or false if it
1955          * can't be determined. Loads the image size directly from the file ignoring caches.
1956          *
1957          * @note Use getWidth()/getHeight() instead of this method unless you have a
1958          *  a good reason. This method skips all caches.
1959          *
1960          * @param string $filePath The path to the file (e.g. From getLocalPathRef() )
1961          * @return array The width, followed by height, with optionally more things after
1962          */
1963         function getImageSize( $filePath ) {
1964                 if ( !$this->getHandler() ) {
1965                         return false;
1966                 }
1967
1968                 return $this->getHandler()->getImageSize( $this, $filePath );
1969         }
1970
1971         /**
1972          * Get the URL of the image description page. May return false if it is
1973          * unknown or not applicable.
1974          *
1975          * @return string
1976          */
1977         function getDescriptionUrl() {
1978                 if ( $this->repo ) {
1979                         return $this->repo->getDescriptionUrl( $this->getName() );
1980                 } else {
1981                         return false;
1982                 }
1983         }
1984
1985         /**
1986          * Get the HTML text of the description page, if available
1987          *
1988          * @param bool|Language $lang Optional language to fetch description in
1989          * @return string
1990          */
1991         function getDescriptionText( $lang = false ) {
1992                 global $wgMemc, $wgLang;
1993                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1994                         return false;
1995                 }
1996                 if ( !$lang ) {
1997                         $lang = $wgLang;
1998                 }
1999                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $lang->getCode() );
2000                 if ( $renderUrl ) {
2001                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
2002                                 wfDebug( "Attempting to get the description from cache..." );
2003                                 $key = $this->repo->getLocalCacheKey(
2004                                         'RemoteFileDescription',
2005                                         'url',
2006                                         $lang->getCode(),
2007                                         $this->getName()
2008                                 );
2009                                 $obj = $wgMemc->get( $key );
2010                                 if ( $obj ) {
2011                                         wfDebug( "success!\n" );
2012
2013                                         return $obj;
2014                                 }
2015                                 wfDebug( "miss\n" );
2016                         }
2017                         wfDebug( "Fetching shared description from $renderUrl\n" );
2018                         $res = Http::get( $renderUrl );
2019                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
2020                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
2021                         }
2022
2023                         return $res;
2024                 } else {
2025                         return false;
2026                 }
2027         }
2028
2029         /**
2030          * Get description of file revision
2031          * STUB
2032          *
2033          * @param int $audience One of:
2034          *   File::FOR_PUBLIC       to be displayed to all users
2035          *   File::FOR_THIS_USER    to be displayed to the given user
2036          *   File::RAW              get the description regardless of permissions
2037          * @param User $user User object to check for, only if FOR_THIS_USER is
2038          *   passed to the $audience parameter
2039          * @return string
2040          */
2041         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
2042                 return null;
2043         }
2044
2045         /**
2046          * Get the 14-character timestamp of the file upload
2047          *
2048          * @return string|bool TS_MW timestamp or false on failure
2049          */
2050         function getTimestamp() {
2051                 $this->assertRepoDefined();
2052
2053                 return $this->repo->getFileTimestamp( $this->getPath() );
2054         }
2055
2056         /**
2057          * Get the SHA-1 base 36 hash of the file
2058          *
2059          * @return string
2060          */
2061         function getSha1() {
2062                 $this->assertRepoDefined();
2063
2064                 return $this->repo->getFileSha1( $this->getPath() );
2065         }
2066
2067         /**
2068          * Get the deletion archive key, "<sha1>.<ext>"
2069          *
2070          * @return string
2071          */
2072         function getStorageKey() {
2073                 $hash = $this->getSha1();
2074                 if ( !$hash ) {
2075                         return false;
2076                 }
2077                 $ext = $this->getExtension();
2078                 $dotExt = $ext === '' ? '' : ".$ext";
2079
2080                 return $hash . $dotExt;
2081         }
2082
2083         /**
2084          * Determine if the current user is allowed to view a particular
2085          * field of this file, if it's marked as deleted.
2086          * STUB
2087          * @param int $field
2088          * @param User $user User object to check, or null to use $wgUser
2089          * @return bool
2090          */
2091         function userCan( $field, User $user = null ) {
2092                 return true;
2093         }
2094
2095         /**
2096          * @return array HTTP header name/value map to use for HEAD/GET request responses
2097          */
2098         function getStreamHeaders() {
2099                 $handler = $this->getHandler();
2100                 if ( $handler ) {
2101                         return $handler->getStreamHeaders( $this->getMetadata() );
2102                 } else {
2103                         return array();
2104                 }
2105         }
2106
2107         /**
2108          * @return string
2109          */
2110         function getLongDesc() {
2111                 $handler = $this->getHandler();
2112                 if ( $handler ) {
2113                         return $handler->getLongDesc( $this );
2114                 } else {
2115                         return MediaHandler::getGeneralLongDesc( $this );
2116                 }
2117         }
2118
2119         /**
2120          * @return string
2121          */
2122         function getShortDesc() {
2123                 $handler = $this->getHandler();
2124                 if ( $handler ) {
2125                         return $handler->getShortDesc( $this );
2126                 } else {
2127                         return MediaHandler::getGeneralShortDesc( $this );
2128                 }
2129         }
2130
2131         /**
2132          * @return string
2133          */
2134         function getDimensionsString() {
2135                 $handler = $this->getHandler();
2136                 if ( $handler ) {
2137                         return $handler->getDimensionsString( $this );
2138                 } else {
2139                         return '';
2140                 }
2141         }
2142
2143         /**
2144          * @return string
2145          */
2146         function getRedirected() {
2147                 return $this->redirected;
2148         }
2149
2150         /**
2151          * @return Title|null
2152          */
2153         function getRedirectedTitle() {
2154                 if ( $this->redirected ) {
2155                         if ( !$this->redirectTitle ) {
2156                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
2157                         }
2158
2159                         return $this->redirectTitle;
2160                 }
2161
2162                 return null;
2163         }
2164
2165         /**
2166          * @param string $from
2167          * @return void
2168          */
2169         function redirectedFrom( $from ) {
2170                 $this->redirected = $from;
2171         }
2172
2173         /**
2174          * @return bool
2175          */
2176         function isMissing() {
2177                 return false;
2178         }
2179
2180         /**
2181          * Check if this file object is small and can be cached
2182          * @return bool
2183          */
2184         public function isCacheable() {
2185                 return true;
2186         }
2187
2188         /**
2189          * Assert that $this->repo is set to a valid FileRepo instance
2190          * @throws MWException
2191          */
2192         protected function assertRepoDefined() {
2193                 if ( !( $this->repo instanceof $this->repoClass ) ) {
2194                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
2195                 }
2196         }
2197
2198         /**
2199          * Assert that $this->title is set to a Title
2200          * @throws MWException
2201          */
2202         protected function assertTitleDefined() {
2203                 if ( !( $this->title instanceof Title ) ) {
2204                         throw new MWException( "A Title object is not set for this File.\n" );
2205                 }
2206         }
2207
2208         /**
2209          * True if creating thumbnails from the file is large or otherwise resource-intensive.
2210          * @return bool
2211          */
2212         public function isExpensiveToThumbnail() {
2213                 $handler = $this->getHandler();
2214                 return $handler ? $handler->isExpensiveToThumbnail( $this ) : false;
2215         }
2216 }