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 );
 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          * @returns 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          */
1291         function migrateThumbFile( $thumbName ) {
1292         }
1293
1294         /**
1295          * Get a MediaHandler instance for this file
1296          *
1297          * @return MediaHandler|bool Registered MediaHandler for file's MIME type
1298          *   or false if none found
1299          */
1300         function getHandler() {
1301                 if ( !isset( $this->handler ) ) {
1302                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1303                 }
1304
1305                 return $this->handler;
1306         }
1307
1308         /**
1309          * Get a ThumbnailImage representing a file type icon
1310          *
1311          * @return ThumbnailImage
1312          */
1313         function iconThumb() {
1314                 global $wgStylePath, $wgStyleDirectory;
1315
1316                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1317                 foreach ( $try as $icon ) {
1318                         $path = '/common/images/icons/' . $icon;
1319                         $filepath = $wgStyleDirectory . $path;
1320                         if ( file_exists( $filepath ) ) { // always FS
1321                                 $params = array( 'width' => 120, 'height' => 120 );
1322
1323                                 return new ThumbnailImage( $this, $wgStylePath . $path, false, $params );
1324                         }
1325                 }
1326
1327                 return null;
1328         }
1329
1330         /**
1331          * Get last thumbnailing error.
1332          * Largely obsolete.
1333          */
1334         function getLastError() {
1335                 return $this->lastError;
1336         }
1337
1338         /**
1339          * Get all thumbnail names previously generated for this file
1340          * STUB
1341          * Overridden by LocalFile
1342          * @return array
1343          */
1344         function getThumbnails() {
1345                 return array();
1346         }
1347
1348         /**
1349          * Purge shared caches such as thumbnails and DB data caching
1350          * STUB
1351          * Overridden by LocalFile
1352          * @param array $options Options, which include:
1353          *   'forThumbRefresh' : The purging is only to refresh thumbnails
1354          */
1355         function purgeCache( $options = array() ) {
1356         }
1357
1358         /**
1359          * Purge the file description page, but don't go after
1360          * pages using the file. Use when modifying file history
1361          * but not the current data.
1362          */
1363         function purgeDescription() {
1364                 $title = $this->getTitle();
1365                 if ( $title ) {
1366                         $title->invalidateCache();
1367                         $title->purgeSquid();
1368                 }
1369         }
1370
1371         /**
1372          * Purge metadata and all affected pages when the file is created,
1373          * deleted, or majorly updated.
1374          */
1375         function purgeEverything() {
1376                 // Delete thumbnails and refresh file metadata cache
1377                 $this->purgeCache();
1378                 $this->purgeDescription();
1379
1380                 // Purge cache of all pages using this file
1381                 $title = $this->getTitle();
1382                 if ( $title ) {
1383                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1384                         $update->doUpdate();
1385                 }
1386         }
1387
1388         /**
1389          * Return a fragment of the history of file.
1390          *
1391          * STUB
1392          * @param int $limit Limit of rows to return
1393          * @param string $start Only revisions older than $start will be returned
1394          * @param string $end Only revisions newer than $end will be returned
1395          * @param bool $inc Include the endpoints of the time range
1396          *
1397          * @return array
1398          */
1399         function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
1400                 return array();
1401         }
1402
1403         /**
1404          * Return the history of this file, line by line. Starts with current version,
1405          * then old versions. Should return an object similar to an image/oldimage
1406          * database row.
1407          *
1408          * STUB
1409          * Overridden in LocalFile
1410          * @return bool
1411          */
1412         public function nextHistoryLine() {
1413                 return false;
1414         }
1415
1416         /**
1417          * Reset the history pointer to the first element of the history.
1418          * Always call this function after using nextHistoryLine() to free db resources
1419          * STUB
1420          * Overridden in LocalFile.
1421          */
1422         public function resetHistory() {
1423         }
1424
1425         /**
1426          * Get the filename hash component of the directory including trailing slash,
1427          * e.g. f/fa/
1428          * If the repository is not hashed, returns an empty string.
1429          *
1430          * @return string
1431          */
1432         function getHashPath() {
1433                 if ( !isset( $this->hashPath ) ) {
1434                         $this->assertRepoDefined();
1435                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1436                 }
1437
1438                 return $this->hashPath;
1439         }
1440
1441         /**
1442          * Get the path of the file relative to the public zone root.
1443          * This function is overriden in OldLocalFile to be like getArchiveRel().
1444          *
1445          * @return string
1446          */
1447         function getRel() {
1448                 return $this->getHashPath() . $this->getName();
1449         }
1450
1451         /**
1452          * Get the path of an archived file relative to the public zone root
1453          *
1454          * @param bool|string $suffix If not false, the name of an archived thumbnail file
1455          *
1456          * @return string
1457          */
1458         function getArchiveRel( $suffix = false ) {
1459                 $path = 'archive/' . $this->getHashPath();
1460                 if ( $suffix === false ) {
1461                         $path = substr( $path, 0, -1 );
1462                 } else {
1463                         $path .= $suffix;
1464                 }
1465
1466                 return $path;
1467         }
1468
1469         /**
1470          * Get the path, relative to the thumbnail zone root, of the
1471          * thumbnail directory or a particular file if $suffix is specified
1472          *
1473          * @param bool|string $suffix If not false, the name of a thumbnail file
1474          * @return string
1475          */
1476         function getThumbRel( $suffix = false ) {
1477                 $path = $this->getRel();
1478                 if ( $suffix !== false ) {
1479                         $path .= '/' . $suffix;
1480                 }
1481
1482                 return $path;
1483         }
1484
1485         /**
1486          * Get urlencoded path of the file relative to the public zone root.
1487          * This function is overriden in OldLocalFile to be like getArchiveUrl().
1488          *
1489          * @return string
1490          */
1491         function getUrlRel() {
1492                 return $this->getHashPath() . rawurlencode( $this->getName() );
1493         }
1494
1495         /**
1496          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1497          * or a specific thumb if the $suffix is given.
1498          *
1499          * @param string $archiveName The timestamped name of an archived image
1500          * @param bool|string $suffix If not false, the name of a thumbnail file
1501          * @return string
1502          */
1503         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1504                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1505                 if ( $suffix === false ) {
1506                         $path = substr( $path, 0, -1 );
1507                 } else {
1508                         $path .= $suffix;
1509                 }
1510
1511                 return $path;
1512         }
1513
1514         /**
1515          * Get the path of the archived file.
1516          *
1517          * @param bool|string $suffix If not false, the name of an archived file.
1518          * @return string
1519          */
1520         function getArchivePath( $suffix = false ) {
1521                 $this->assertRepoDefined();
1522
1523                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1524         }
1525
1526         /**
1527          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1528          *
1529          * @param string $archiveName The timestamped name of an archived image
1530          * @param bool|string $suffix If not false, the name of a thumbnail file
1531          * @return string
1532          */
1533         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1534                 $this->assertRepoDefined();
1535
1536                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1537                 $this->getArchiveThumbRel( $archiveName, $suffix );
1538         }
1539
1540         /**
1541          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1542          *
1543          * @param bool|string $suffix If not false, the name of a thumbnail file
1544          * @return string
1545          */
1546         function getThumbPath( $suffix = false ) {
1547                 $this->assertRepoDefined();
1548
1549                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1550         }
1551
1552         /**
1553          * Get the path of the transcoded directory, or a particular file if $suffix is specified
1554          *
1555          * @param bool|string $suffix If not false, the name of a media file
1556          * @return string
1557          */
1558         function getTranscodedPath( $suffix = false ) {
1559                 $this->assertRepoDefined();
1560
1561                 return $this->repo->getZonePath( 'transcoded' ) . '/' . $this->getThumbRel( $suffix );
1562         }
1563
1564         /**
1565          * Get the URL of the archive directory, or a particular file if $suffix is specified
1566          *
1567          * @param bool|string $suffix If not false, the name of an archived file
1568          * @return string
1569          */
1570         function getArchiveUrl( $suffix = false ) {
1571                 $this->assertRepoDefined();
1572                 $ext = $this->getExtension();
1573                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1574                 if ( $suffix === false ) {
1575                         $path = substr( $path, 0, -1 );
1576                 } else {
1577                         $path .= rawurlencode( $suffix );
1578                 }
1579
1580                 return $path;
1581         }
1582
1583         /**
1584          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1585          *
1586          * @param string $archiveName The timestamped name of an archived image
1587          * @param bool|string $suffix If not false, the name of a thumbnail file
1588          * @return string
1589          */
1590         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1591                 $this->assertRepoDefined();
1592                 $ext = $this->getExtension();
1593                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1594                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1595                 if ( $suffix === false ) {
1596                         $path = substr( $path, 0, -1 );
1597                 } else {
1598                         $path .= rawurlencode( $suffix );
1599                 }
1600
1601                 return $path;
1602         }
1603
1604         /**
1605          * Get the URL of the zone directory, or a particular file if $suffix is specified
1606          *
1607          * @param string $zone Name of requested zone
1608          * @param bool|string $suffix If not false, the name of a file in zone
1609          * @return string path
1610          */
1611         function getZoneUrl( $zone, $suffix = false ) {
1612                 $this->assertRepoDefined();
1613                 $ext = $this->getExtension();
1614                 $path = $this->repo->getZoneUrl( $zone, $ext ) . '/' . $this->getUrlRel();
1615                 if ( $suffix !== false ) {
1616                         $path .= '/' . rawurlencode( $suffix );
1617                 }
1618
1619                 return $path;
1620         }
1621
1622         /**
1623          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1624          *
1625          * @param bool|string $suffix If not false, the name of a thumbnail file
1626          * @return string path
1627          */
1628         function getThumbUrl( $suffix = false ) {
1629                 return $this->getZoneUrl( 'thumb', $suffix );
1630         }
1631
1632         /**
1633          * Get the URL of the transcoded directory, or a particular file if $suffix is specified
1634          *
1635          * @param bool|string $suffix If not false, the name of a media file
1636          * @return string path
1637          */
1638         function getTranscodedUrl( $suffix = false ) {
1639                 return $this->getZoneUrl( 'transcoded', $suffix );
1640         }
1641
1642         /**
1643          * Get the public zone virtual URL for a current version source file
1644          *
1645          * @param bool|string $suffix If not false, the name of a thumbnail file
1646          * @return string
1647          */
1648         function getVirtualUrl( $suffix = false ) {
1649                 $this->assertRepoDefined();
1650                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1651                 if ( $suffix !== false ) {
1652                         $path .= '/' . rawurlencode( $suffix );
1653                 }
1654
1655                 return $path;
1656         }
1657
1658         /**
1659          * Get the public zone virtual URL for an archived version source file
1660          *
1661          * @param bool|string $suffix If not false, the name of a thumbnail file
1662          * @return string
1663          */
1664         function getArchiveVirtualUrl( $suffix = false ) {
1665                 $this->assertRepoDefined();
1666                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1667                 if ( $suffix === false ) {
1668                         $path = substr( $path, 0, -1 );
1669                 } else {
1670                         $path .= rawurlencode( $suffix );
1671                 }
1672
1673                 return $path;
1674         }
1675
1676         /**
1677          * Get the virtual URL for a thumbnail file or directory
1678          *
1679          * @param bool|string $suffix If not false, the name of a thumbnail file
1680          * @return string
1681          */
1682         function getThumbVirtualUrl( $suffix = false ) {
1683                 $this->assertRepoDefined();
1684                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1685                 if ( $suffix !== false ) {
1686                         $path .= '/' . rawurlencode( $suffix );
1687                 }
1688
1689                 return $path;
1690         }
1691
1692         /**
1693          * @return bool
1694          */
1695         function isHashed() {
1696                 $this->assertRepoDefined();
1697
1698                 return (bool)$this->repo->getHashLevels();
1699         }
1700
1701         /**
1702          * @throws MWException
1703          */
1704         function readOnlyError() {
1705                 throw new MWException( get_class( $this ) . ': write operations are not supported' );
1706         }
1707
1708         /**
1709          * Record a file upload in the upload log and the image table
1710          * STUB
1711          * Overridden by LocalFile
1712          * @param string $oldver
1713          * @param string $desc
1714          * @param string $license
1715          * @param string $copyStatus
1716          * @param string $source
1717          * @param bool $watch
1718          * @param string|bool $timestamp
1719          * @param null|User $user User object or null to use $wgUser
1720          * @return bool
1721          * @throws MWException
1722          */
1723         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
1724                 $watch = false, $timestamp = false, User $user = null
1725         ) {
1726                 $this->readOnlyError();
1727         }
1728
1729         /**
1730          * Move or copy a file to its public location. If a file exists at the
1731          * destination, move it to an archive. Returns a FileRepoStatus object with
1732          * the archive name in the "value" member on success.
1733          *
1734          * The archive name should be passed through to recordUpload for database
1735          * registration.
1736          *
1737          * Options to $options include:
1738          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1739          *
1740          * @param string $srcPath Local filesystem path to the source image
1741          * @param int $flags A bitwise combination of:
1742          *   File::DELETE_SOURCE    Delete the source file, i.e. move rather than copy
1743          * @param array $options Optional additional parameters
1744          * @return FileRepoStatus object. On success, the value member contains the
1745          *   archive name, or an empty string if it was a new file.
1746          *
1747          * STUB
1748          * Overridden by LocalFile
1749          */
1750         function publish( $srcPath, $flags = 0, array $options = array() ) {
1751                 $this->readOnlyError();
1752         }
1753
1754         /**
1755          * @return bool
1756          */
1757         function formatMetadata() {
1758                 if ( !$this->getHandler() ) {
1759                         return false;
1760                 }
1761
1762                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
1763         }
1764
1765         /**
1766          * Returns true if the file comes from the local file repository.
1767          *
1768          * @return bool
1769          */
1770         function isLocal() {
1771                 return $this->repo && $this->repo->isLocal();
1772         }
1773
1774         /**
1775          * Returns the name of the repository.
1776          *
1777          * @return string
1778          */
1779         function getRepoName() {
1780                 return $this->repo ? $this->repo->getName() : 'unknown';
1781         }
1782
1783         /**
1784          * Returns the repository
1785          *
1786          * @return FileRepo|LocalRepo|bool
1787          */
1788         function getRepo() {
1789                 return $this->repo;
1790         }
1791
1792         /**
1793          * Returns true if the image is an old version
1794          * STUB
1795          *
1796          * @return bool
1797          */
1798         function isOld() {
1799                 return false;
1800         }
1801
1802         /**
1803          * Is this file a "deleted" file in a private archive?
1804          * STUB
1805          *
1806          * @param int $field One of DELETED_* bitfield constants
1807          * @return bool
1808          */
1809         function isDeleted( $field ) {
1810                 return false;
1811         }
1812
1813         /**
1814          * Return the deletion bitfield
1815          * STUB
1816          * @return int
1817          */
1818         function getVisibility() {
1819                 return 0;
1820         }
1821
1822         /**
1823          * Was this file ever deleted from the wiki?
1824          *
1825          * @return bool
1826          */
1827         function wasDeleted() {
1828                 $title = $this->getTitle();
1829
1830                 return $title && $title->isDeletedQuick();
1831         }
1832
1833         /**
1834          * Move file to the new title
1835          *
1836          * Move current, old version and all thumbnails
1837          * to the new filename. Old file is deleted.
1838          *
1839          * Cache purging is done; checks for validity
1840          * and logging are caller's responsibility
1841          *
1842          * @param Title $target New file name
1843          * @return FileRepoStatus
1844          */
1845         function move( $target ) {
1846                 $this->readOnlyError();
1847         }
1848
1849         /**
1850          * Delete all versions of the file.
1851          *
1852          * Moves the files into an archive directory (or deletes them)
1853          * and removes the database rows.
1854          *
1855          * Cache purging is done; logging is caller's responsibility.
1856          *
1857          * @param string $reason
1858          * @param bool $suppress Hide content from sysops?
1859          * @param User|null $user
1860          * @return bool Boolean on success, false on some kind of failure
1861          * STUB
1862          * Overridden by LocalFile
1863          */
1864         function delete( $reason, $suppress = false, $user = null ) {
1865                 $this->readOnlyError();
1866         }
1867
1868         /**
1869          * Restore all or specified deleted revisions to the given file.
1870          * Permissions and logging are left to the caller.
1871          *
1872          * May throw database exceptions on error.
1873          *
1874          * @param array $versions Set of record ids of deleted items to restore,
1875          *   or empty to restore all revisions.
1876          * @param bool $unsuppress Remove restrictions on content upon restoration?
1877          * @return int|bool The number of file revisions restored if successful,
1878          *   or false on failure
1879          * STUB
1880          * Overridden by LocalFile
1881          */
1882         function restore( $versions = array(), $unsuppress = false ) {
1883                 $this->readOnlyError();
1884         }
1885
1886         /**
1887          * Returns 'true' if this file is a type which supports multiple pages,
1888          * e.g. DJVU or PDF. Note that this may be true even if the file in
1889          * question only has a single page.
1890          *
1891          * @return bool
1892          */
1893         function isMultipage() {
1894                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1895         }
1896
1897         /**
1898          * Returns the number of pages of a multipage document, or false for
1899          * documents which aren't multipage documents
1900          *
1901          * @return bool|int
1902          */
1903         function pageCount() {
1904                 if ( !isset( $this->pageCount ) ) {
1905                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1906                                 $this->pageCount = $this->handler->pageCount( $this );
1907                         } else {
1908                                 $this->pageCount = false;
1909                         }
1910                 }
1911
1912                 return $this->pageCount;
1913         }
1914
1915         /**
1916          * Calculate the height of a thumbnail using the source and destination width
1917          *
1918          * @param int $srcWidth
1919          * @param int $srcHeight
1920          * @param int $dstWidth
1921          *
1922          * @return int
1923          */
1924         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1925                 // Exact integer multiply followed by division
1926                 if ( $srcWidth == 0 ) {
1927                         return 0;
1928                 } else {
1929                         return round( $srcHeight * $dstWidth / $srcWidth );
1930                 }
1931         }
1932
1933         /**
1934          * Get an image size array like that returned by getImageSize(), or false if it
1935          * can't be determined. Loads the image size directly from the file ignoring caches.
1936          *
1937          * @note Use getWidth()/getHeight() instead of this method unless you have a
1938          *  a good reason. This method skips all caches.
1939          *
1940          * @param string $fileName The path to the file (e.g. From getLocalPathRef() )
1941          * @return array The width, followed by height, with optionally more things after
1942          */
1943         function getImageSize( $filePath ) {
1944                 if ( !$this->getHandler() ) {
1945                         return false;
1946                 }
1947
1948                 return $this->getHandler()->getImageSize( $this, $filePath );
1949         }
1950
1951         /**
1952          * Get the URL of the image description page. May return false if it is
1953          * unknown or not applicable.
1954          *
1955          * @return string
1956          */
1957         function getDescriptionUrl() {
1958                 if ( $this->repo ) {
1959                         return $this->repo->getDescriptionUrl( $this->getName() );
1960                 } else {
1961                         return false;
1962                 }
1963         }
1964
1965         /**
1966          * Get the HTML text of the description page, if available
1967          *
1968          * @param bool|Language $lang Optional language to fetch description in
1969          * @return string
1970          */
1971         function getDescriptionText( $lang = false ) {
1972                 global $wgMemc, $wgLang;
1973                 if ( !$this->repo || !$this->repo->fetchDescription ) {
1974                         return false;
1975                 }
1976                 if ( !$lang ) {
1977                         $lang = $wgLang;
1978                 }
1979                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $lang->getCode() );
1980                 if ( $renderUrl ) {
1981                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1982                                 wfDebug( "Attempting to get the description from cache..." );
1983                                 $key = $this->repo->getLocalCacheKey(
1984                                         'RemoteFileDescription',
1985                                         'url',
1986                                         $lang->getCode(),
1987                                         $this->getName()
1988                                 );
1989                                 $obj = $wgMemc->get( $key );
1990                                 if ( $obj ) {
1991                                         wfDebug( "success!\n" );
1992
1993                                         return $obj;
1994                                 }
1995                                 wfDebug( "miss\n" );
1996                         }
1997                         wfDebug( "Fetching shared description from $renderUrl\n" );
1998                         $res = Http::get( $renderUrl );
1999                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
2000                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
2001                         }
2002
2003                         return $res;
2004                 } else {
2005                         return false;
2006                 }
2007         }
2008
2009         /**
2010          * Get description of file revision
2011          * STUB
2012          *
2013          * @param int $audience One of:
2014          *   File::FOR_PUBLIC       to be displayed to all users
2015          *   File::FOR_THIS_USER    to be displayed to the given user
2016          *   File::RAW              get the description regardless of permissions
2017          * @param User $user User object to check for, only if FOR_THIS_USER is
2018          *   passed to the $audience parameter
2019          * @return string
2020          */
2021         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
2022                 return null;
2023         }
2024
2025         /**
2026          * Get the 14-character timestamp of the file upload
2027          *
2028          * @return string|bool TS_MW timestamp or false on failure
2029          */
2030         function getTimestamp() {
2031                 $this->assertRepoDefined();
2032
2033                 return $this->repo->getFileTimestamp( $this->getPath() );
2034         }
2035
2036         /**
2037          * Get the SHA-1 base 36 hash of the file
2038          *
2039          * @return string
2040          */
2041         function getSha1() {
2042                 $this->assertRepoDefined();
2043
2044                 return $this->repo->getFileSha1( $this->getPath() );
2045         }
2046
2047         /**
2048          * Get the deletion archive key, "<sha1>.<ext>"
2049          *
2050          * @return string
2051          */
2052         function getStorageKey() {
2053                 $hash = $this->getSha1();
2054                 if ( !$hash ) {
2055                         return false;
2056                 }
2057                 $ext = $this->getExtension();
2058                 $dotExt = $ext === '' ? '' : ".$ext";
2059
2060                 return $hash . $dotExt;
2061         }
2062
2063         /**
2064          * Determine if the current user is allowed to view a particular
2065          * field of this file, if it's marked as deleted.
2066          * STUB
2067          * @param int $field
2068          * @param User $user User object to check, or null to use $wgUser
2069          * @return bool
2070          */
2071         function userCan( $field, User $user = null ) {
2072                 return true;
2073         }
2074
2075         /**
2076          * Get an associative array containing information about a file in the local filesystem.
2077          *
2078          * @param string $path Absolute local filesystem path
2079          * @param string|bool $ext The file extension, or true to extract it from
2080          *   the filename. Set it to false to ignore the extension.
2081          *
2082          * @return array
2083          * @deprecated since 1.19
2084          */
2085         static function getPropsFromPath( $path, $ext = true ) {
2086                 wfDebug( __METHOD__ . ": Getting file info for $path\n" );
2087                 wfDeprecated( __METHOD__, '1.19' );
2088
2089                 $fsFile = new FSFile( $path );
2090
2091                 return $fsFile->getProps();
2092         }
2093
2094         /**
2095          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
2096          * encoding, zero padded to 31 digits.
2097          *
2098          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
2099          * fairly neatly.
2100          *
2101          * @param string $path
2102          * @return bool|string False on failure
2103          * @deprecated since 1.19
2104          */
2105         static function sha1Base36( $path ) {
2106                 wfDeprecated( __METHOD__, '1.19' );
2107
2108                 $fsFile = new FSFile( $path );
2109
2110                 return $fsFile->getSha1Base36();
2111         }
2112
2113         /**
2114          * @return array HTTP header name/value map to use for HEAD/GET request responses
2115          */
2116         function getStreamHeaders() {
2117                 $handler = $this->getHandler();
2118                 if ( $handler ) {
2119                         return $handler->getStreamHeaders( $this->getMetadata() );
2120                 } else {
2121                         return array();
2122                 }
2123         }
2124
2125         /**
2126          * @return string
2127          */
2128         function getLongDesc() {
2129                 $handler = $this->getHandler();
2130                 if ( $handler ) {
2131                         return $handler->getLongDesc( $this );
2132                 } else {
2133                         return MediaHandler::getGeneralLongDesc( $this );
2134                 }
2135         }
2136
2137         /**
2138          * @return string
2139          */
2140         function getShortDesc() {
2141                 $handler = $this->getHandler();
2142                 if ( $handler ) {
2143                         return $handler->getShortDesc( $this );
2144                 } else {
2145                         return MediaHandler::getGeneralShortDesc( $this );
2146                 }
2147         }
2148
2149         /**
2150          * @return string
2151          */
2152         function getDimensionsString() {
2153                 $handler = $this->getHandler();
2154                 if ( $handler ) {
2155                         return $handler->getDimensionsString( $this );
2156                 } else {
2157                         return '';
2158                 }
2159         }
2160
2161         /**
2162          * @return string
2163          */
2164         function getRedirected() {
2165                 return $this->redirected;
2166         }
2167
2168         /**
2169          * @return Title|null
2170          */
2171         function getRedirectedTitle() {
2172                 if ( $this->redirected ) {
2173                         if ( !$this->redirectTitle ) {
2174                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
2175                         }
2176
2177                         return $this->redirectTitle;
2178                 }
2179
2180                 return null;
2181         }
2182
2183         /**
2184          * @param string $from
2185          * @return void
2186          */
2187         function redirectedFrom( $from ) {
2188                 $this->redirected = $from;
2189         }
2190
2191         /**
2192          * @return bool
2193          */
2194         function isMissing() {
2195                 return false;
2196         }
2197
2198         /**
2199          * Check if this file object is small and can be cached
2200          * @return bool
2201          */
2202         public function isCacheable() {
2203                 return true;
2204         }
2205
2206         /**
2207          * Assert that $this->repo is set to a valid FileRepo instance
2208          * @throws MWException
2209          */
2210         protected function assertRepoDefined() {
2211                 if ( !( $this->repo instanceof $this->repoClass ) ) {
2212                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
2213                 }
2214         }
2215
2216         /**
2217          * Assert that $this->title is set to a Title
2218          * @throws MWException
2219          */
2220         protected function assertTitleDefined() {
2221                 if ( !( $this->title instanceof Title ) ) {
2222                         throw new MWException( "A Title object is not set for this File.\n" );
2223                 }
2224         }
2225
2226         /**
2227          * True if creating thumbnails from the file is large or otherwise resource-intensive.
2228          * @return bool
2229          */
2230         public function isExpensiveToThumbnail() {
2231                 $handler = $this->getHandler();
2232                 return $handler ? $handler->isExpensiveToThumbnail( $this ) : false;
2233         }
2234 }