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