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 implements IDBAccessObject {
  51         // Bitfield values akin to the Revision deletion constants
  52         const DELETED_FILE = 1;
  53         const DELETED_COMMENT = 2;
  54         const DELETED_USER = 4;
  55         const DELETED_RESTRICTED = 8;
  56
  57         /** Force rendering in the current process */
  58         const RENDER_NOW = 1;
  59         /**
  60          * Force rendering even if thumbnail already exist and using RENDER_NOW
  61          * I.e. you have to pass both flags: File::RENDER_NOW | File::RENDER_FORCE
  62          */
  63         const RENDER_FORCE = 2;
  64
  65         const DELETE_SOURCE = 1;
  66
  67         // Audience options for File::getDescription()
  68         const FOR_PUBLIC = 1;
  69         const FOR_THIS_USER = 2;
  70         const RAW = 3;
  71
  72         // Options for File::thumbName()
  73         const THUMB_FULL_NAME = 1;
  74
  75         /**
  76          * Some member variables can be lazy-initialised using __get(). The
  77          * initialisation function for these variables is always a function named
  78          * like getVar(), where Var is the variable name with upper-case first
  79          * letter.
  80          *
  81          * The following variables are initialised in this way in this base class:
  82          *    name, extension, handler, path, canRender, isSafeFile,
  83          *    transformScript, hashPath, pageCount, url
  84          *
  85          * Code within this class should generally use the accessor function
  86          * directly, since __get() isn't re-entrant and therefore causes bugs that
  87          * depend on initialisation order.
  88          */
  89
  90         /**
  91          * The following member variables are not lazy-initialised
  92          */
  93
  94         /** @var FileRepo|LocalRepo|ForeignAPIRepo|bool */
  95         public $repo;
  96
  97         /** @var Title|string|bool */
  98         protected $title;
  99
 100         /** @var string Text of last error */
 101         protected $lastError;
 102
 103         /** @var string Main part of the title, with underscores (Title::getDBkey) */
 104         protected $redirected;
 105
 106         /** @var Title */
 107         protected $redirectedTitle;
 108
 109         /** @var FSFile|bool False if undefined */
 110         protected $fsFile;
 111
 112         /** @var MediaHandler */
 113         protected $handler;
 114
 115         /** @var string The URL corresponding to one of the four basic zones */
 116         protected $url;
 117
 118         /** @var string File extension */
 119         protected $extension;
 120
 121         /** @var string The name of a file from its title object */
 122         protected $name;
 123
 124         /** @var string The storage path corresponding to one of the zones */
 125         protected $path;
 126
 127         /** @var string Relative path including trailing slash */
 128         protected $hashPath;
 129
 130         /** @var string Number of pages of a multipage document, or false for
 131          *    documents which aren't multipage documents
 132          */
 133         protected $pageCount;
 134
 135         /** @var string URL of transformscript (for example thumb.php) */
 136         protected $transformScript;
 137
 138         /** @var Title */
 139         protected $redirectTitle;
 140
 141         /** @var bool Whether the output of transform() for this file is likely to be valid. */
 142         protected $canRender;
 143
 144         /** @var bool Whether this media file is in a format that is unlikely to
 145          *    contain viruses or malicious content
 146          */
 147         protected $isSafeFile;
 148
 149         /** @var string Required Repository class type */
 150         protected $repoClass = 'FileRepo';
 151
 152         /** @var array Cache of tmp filepaths pointing to generated bucket thumbnails, keyed by width */
 153         protected $tmpBucketedThumbCache = array();
 154
 155         /**
 156          * Call this constructor from child classes.
 157          *
 158          * Both $title and $repo are optional, though some functions
 159          * may return false or throw exceptions if they are not set.
 160          * Most subclasses will want to call assertRepoDefined() here.
 161          *
 162          * @param Title|string|bool $title
 163          * @param FileRepo|bool $repo
 164          */
 165         function __construct( $title, $repo ) {
 166                 if ( $title !== false ) { // subclasses may not use MW titles
 167                         $title = self::normalizeTitle( $title, 'exception' );
 168                 }
 169                 $this->title = $title;
 170                 $this->repo = $repo;
 171         }
 172
 173         /**
 174          * Given a string or Title object return either a
 175          * valid Title object with namespace NS_FILE or null
 176          *
 177          * @param Title|string $title
 178          * @param string|bool $exception Use 'exception' to throw an error on bad titles
 179          * @throws MWException
 180          * @return Title|null
 181          */
 182         static function normalizeTitle( $title, $exception = false ) {
 183                 $ret = $title;
 184                 if ( $ret instanceof Title ) {
 185                         # Normalize NS_MEDIA -> NS_FILE
 186                         if ( $ret->getNamespace() == NS_MEDIA ) {
 187                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 188                         # Sanity check the title namespace
 189                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 190                                 $ret = null;
 191                         }
 192                 } else {
 193                         # Convert strings to Title objects
 194                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 195                 }
 196                 if ( !$ret && $exception !== false ) {
 197                         throw new MWException( "`$title` is not a valid file title." );
 198                 }
 199
 200                 return $ret;
 201         }
 202
 203         function __get( $name ) {
 204                 $function = array( $this, 'get' . ucfirst( $name ) );
 205                 if ( !is_callable( $function ) ) {
 206                         return null;
 207                 } else {
 208                         $this->$name = call_user_func( $function );
 209
 210                         return $this->$name;
 211                 }
 212         }
 213
 214         /**
 215          * Normalize a file extension to the common form, and ensure it's clean.
 216          * Extensions with non-alphanumeric characters will be discarded.
 217          *
 218          * @param string $ext (without the .)
 219          * @return string
 220          */
 221         static function normalizeExtension( $ext ) {
 222                 $lower = strtolower( $ext );
 223                 $squish = array(
 224                         'htm' => 'html',
 225                         'jpeg' => 'jpg',
 226                         'mpeg' => 'mpg',
 227                         'tiff' => 'tif',
 228                         'ogv' => 'ogg' );
 229                 if ( isset( $squish[$lower] ) ) {
 230                         return $squish[$lower];
 231                 } elseif ( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 232                         return $lower;
 233                 } else {
 234                         return '';
 235                 }
 236         }
 237
 238         /**
 239          * Checks if file extensions are compatible
 240          *
 241          * @param File $old Old file
 242          * @param string $new New name
 243          *
 244          * @return bool|null
 245          */
 246         static function checkExtensionCompatibility( File $old, $new ) {
 247                 $oldMime = $old->getMimeType();
 248                 $n = strrpos( $new, '.' );
 249                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 250                 $mimeMagic = MimeMagic::singleton();
 251
 252                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 253         }
 254
 255         /**
 256          * Upgrade the database row if there is one
 257          * Called by ImagePage
 258          * STUB
 259          */
 260         function upgradeRow() {
 261         }
 262
 263         /**
 264          * Split an internet media type into its two components; if not
 265          * a two-part name, set the minor type to 'unknown'.
 266          *
 267          * @param string $mime "text/html" etc
 268          * @return array ("text", "html") etc
 269          */
 270         public static function splitMime( $mime ) {
 271                 if ( strpos( $mime, '/' ) !== false ) {
 272                         return explode( '/', $mime, 2 );
 273                 } else {
 274                         return array( $mime, 'unknown' );
 275                 }
 276         }
 277
 278         /**
 279          * Callback for usort() to do file sorts by name
 280          *
 281          * @param File $a
 282          * @param File $b
 283          * @return int Result of name comparison
 284          */
 285         public static function compare( File $a, File $b ) {
 286                 return strcmp( $a->getName(), $b->getName() );
 287         }
 288
 289         /**
 290          * Return the name of this file
 291          *
 292          * @return string
 293          */
 294         public function getName() {
 295                 if ( !isset( $this->name ) ) {
 296                         $this->assertRepoDefined();
 297                         $this->name = $this->repo->getNameFromTitle( $this->title );
 298                 }
 299
 300                 return $this->name;
 301         }
 302
 303         /**
 304          * Get the file extension, e.g. "svg"
 305          *
 306          * @return string
 307          */
 308         function getExtension() {
 309                 if ( !isset( $this->extension ) ) {
 310                         $n = strrpos( $this->getName(), '.' );
 311                         $this->extension = self::normalizeExtension(
 312                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 313                 }
 314
 315                 return $this->extension;
 316         }
 317
 318         /**
 319          * Return the associated title object
 320          *
 321          * @return Title
 322          */
 323         public function getTitle() {
 324                 return $this->title;
 325         }
 326
 327         /**
 328          * Return the title used to find this file
 329          *
 330          * @return Title
 331          */
 332         public function getOriginalTitle() {
 333                 if ( $this->redirected ) {
 334                         return $this->getRedirectedTitle();
 335                 }
 336
 337                 return $this->title;
 338         }
 339
 340         /**
 341          * Return the URL of the file
 342          *
 343          * @return string
 344          */
 345         public function getUrl() {
 346                 if ( !isset( $this->url ) ) {
 347                         $this->assertRepoDefined();
 348                         $ext = $this->getExtension();
 349                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 350                 }
 351
 352                 return $this->url;
 353         }
 354
 355         /**
 356          * Return a fully-qualified URL to the file.
 357          * Upload URL paths _may or may not_ be fully qualified, so
 358          * we check. Local paths are assumed to belong on $wgServer.
 359          *
 360          * @return string
 361          */
 362         public function getFullUrl() {
 363                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 364         }
 365
 366         /**
 367          * @return string
 368          */
 369         public function getCanonicalUrl() {
 370                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 371         }
 372
 373         /**
 374          * @return string
 375          */
 376         function getViewURL() {
 377                 if ( $this->mustRender() ) {
 378                         if ( $this->canRender() ) {
 379                                 return $this->createThumb( $this->getWidth() );
 380                         } else {
 381                                 wfDebug( __METHOD__ . ': supposed to render ' . $this->getName() .
 382                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 383
 384                                 return $this->getURL(); #hm... return NULL?
 385                         }
 386                 } else {
 387                         return $this->getURL();
 388                 }
 389         }
 390
 391         /**
 392          * Return the storage path to the file. Note that this does
 393          * not mean that a file actually exists under that location.
 394          *
 395          * This path depends on whether directory hashing is active or not,
 396          * i.e. whether the files are all found in the same directory,
 397          * or in hashed paths like /images/3/3c.
 398          *
 399          * Most callers don't check the return value, but ForeignAPIFile::getPath
 400          * returns false.
 401          *
 402          * @return string|bool ForeignAPIFile::getPath can return false
 403          */
 404         public function getPath() {
 405                 if ( !isset( $this->path ) ) {
 406                         $this->assertRepoDefined();
 407                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 408                 }
 409
 410                 return $this->path;
 411         }
 412
 413         /**
 414          * Get an FS copy or original of this file and return the path.
 415          * Returns false on failure. Callers must not alter the file.
 416          * Temporary files are cleared automatically.
 417          *
 418          * @return string|bool False on failure
 419          */
 420         public function getLocalRefPath() {
 421                 $this->assertRepoDefined();
 422                 if ( !isset( $this->fsFile ) ) {
 423                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 424                         if ( !$this->fsFile ) {
 425                                 $this->fsFile = false; // null => false; cache negative hits
 426                         }
 427                 }
 428
 429                 return ( $this->fsFile )
 430                         ? $this->fsFile->getPath()
 431                         : false;
 432         }
 433
 434         /**
 435          * Return the width of the image. Returns false if the width is unknown
 436          * or undefined.
 437          *
 438          * STUB
 439          * Overridden by LocalFile, UnregisteredLocalFile
 440          *
 441          * @param int $page
 442          * @return int|bool
 443          */
 444         public function getWidth( $page = 1 ) {
 445                 return false;
 446         }
 447
 448         /**
 449          * Return the height of the image. Returns false if the height is unknown
 450          * or undefined
 451          *
 452          * STUB
 453          * Overridden by LocalFile, UnregisteredLocalFile
 454          *
 455          * @param int $page
 456          * @return bool|int False on failure
 457          */
 458         public function getHeight( $page = 1 ) {
 459                 return false;
 460         }
 461
 462         /**
 463          * Return the smallest bucket from $wgThumbnailBuckets which is at least
 464          * $wgThumbnailMinimumBucketDistance larger than $desiredWidth. The returned bucket, if any,
 465          * will always be bigger than $desiredWidth.
 466          *
 467          * @param int $desiredWidth
 468          * @param int $page
 469          * @return bool|int
 470          */
 471         public function getThumbnailBucket( $desiredWidth, $page = 1 ) {
 472                 global $wgThumbnailBuckets, $wgThumbnailMinimumBucketDistance;
 473
 474                 $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          * Load any lazy-loaded file object fields from source
 841          *
 842          * This is only useful when setting $flags
 843          *
 844          * Overridden by LocalFile to actually query the DB
 845          *
 846          * @param integer $flags Bitfield of File::READ_* constants
 847          */
 848         public function load( $flags = 0 ) {
 849         }
 850
 851         /**
 852          * Returns true if file exists in the repository.
 853          *
 854          * Overridden by LocalFile to avoid unnecessary stat calls.
 855          *
 856          * @return bool Whether file exists in the repository.
 857          */
 858         public function exists() {
 859                 return $this->getPath() && $this->repo->fileExists( $this->path );
 860         }
 861
 862         /**
 863          * Returns true if file exists in the repository and can be included in a page.
 864          * It would be unsafe to include private images, making public thumbnails inadvertently
 865          *
 866          * @return bool Whether file exists in the repository and is includable.
 867          */
 868         public function isVisible() {
 869                 return $this->exists();
 870         }
 871
 872         /**
 873          * @return string
 874          */
 875         function getTransformScript() {
 876                 if ( !isset( $this->transformScript ) ) {
 877                         $this->transformScript = false;
 878                         if ( $this->repo ) {
 879                                 $script = $this->repo->getThumbScriptUrl();
 880                                 if ( $script ) {
 881                                         $this->transformScript = wfAppendQuery( $script, array( 'f' => $this->getName() ) );
 882                                 }
 883                         }
 884                 }
 885
 886                 return $this->transformScript;
 887         }
 888
 889         /**
 890          * Get a ThumbnailImage which is the same size as the source
 891          *
 892          * @param array $handlerParams
 893          *
 894          * @return string
 895          */
 896         function getUnscaledThumb( $handlerParams = array() ) {
 897                 $hp =& $handlerParams;
 898                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 899                 $width = $this->getWidth( $page );
 900                 if ( !$width ) {
 901                         return $this->iconThumb();
 902                 }
 903                 $hp['width'] = $width;
 904                 // be sure to ignore any height specification as well (bug 62258)
 905                 unset( $hp['height'] );
 906
 907                 return $this->transform( $hp );
 908         }
 909
 910         /**
 911          * Return the file name of a thumbnail with the specified parameters.
 912          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 913          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 914          *
 915          * @param array $params Handler-specific parameters
 916          * @param int $flags Bitfield that supports THUMB_* constants
 917          * @return string
 918          */
 919         public function thumbName( $params, $flags = 0 ) {
 920                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 921                         ? $this->repo->nameForThumb( $this->getName() )
 922                         : $this->getName();
 923
 924                 return $this->generateThumbName( $name, $params );
 925         }
 926
 927         /**
 928          * Generate a thumbnail file name from a name and specified parameters
 929          *
 930          * @param string $name
 931          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 932          * @return string
 933          */
 934         public function generateThumbName( $name, $params ) {
 935                 if ( !$this->getHandler() ) {
 936                         return null;
 937                 }
 938                 $extension = $this->getExtension();
 939                 list( $thumbExt, ) = $this->getHandler()->getThumbType(
 940                         $extension, $this->getMimeType(), $params );
 941                 $thumbName = $this->getHandler()->makeParamString( $params ) . '-' . $name;
 942                 if ( $thumbExt != $extension ) {
 943                         $thumbName .= ".$thumbExt";
 944                 }
 945
 946                 return $thumbName;
 947         }
 948
 949         /**
 950          * Create a thumbnail of the image having the specified width/height.
 951          * The thumbnail will not be created if the width is larger than the
 952          * image's width. Let the browser do the scaling in this case.
 953          * The thumbnail is stored on disk and is only computed if the thumbnail
 954          * file does not exist OR if it is older than the image.
 955          * Returns the URL.
 956          *
 957          * Keeps aspect ratio of original image. If both width and height are
 958          * specified, the generated image will be no bigger than width x height,
 959          * and will also have correct aspect ratio.
 960          *
 961          * @param int $width Maximum width of the generated thumbnail
 962          * @param int $height Maximum height of the image (optional)
 963          *
 964          * @return string
 965          */
 966         public function createThumb( $width, $height = -1 ) {
 967                 $params = array( 'width' => $width );
 968                 if ( $height != -1 ) {
 969                         $params['height'] = $height;
 970                 }
 971                 $thumb = $this->transform( $params );
 972                 if ( !$thumb || $thumb->isError() ) {
 973                         return '';
 974                 }
 975
 976                 return $thumb->getUrl();
 977         }
 978
 979         /**
 980          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 981          *
 982          * @param string $thumbPath Thumbnail storage path
 983          * @param string $thumbUrl Thumbnail URL
 984          * @param array $params
 985          * @param int $flags
 986          * @return MediaTransformOutput
 987          */
 988         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 989                 global $wgIgnoreImageErrors;
 990
 991                 $handler = $this->getHandler();
 992                 if ( $handler && $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 993                         return $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 994                 } else {
 995                         return new MediaTransformError( 'thumbnail_error',
 996                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 997                 }
 998         }
 999
1000         /**
1001          * Transform a media file
1002          *
1003          * @param array $params An associative array of handler-specific parameters.
1004          *   Typical keys are width, height and page.
1005          * @param int $flags A bitfield, may contain self::RENDER_NOW to force rendering
1006          * @return MediaTransformOutput|bool False on failure
1007          */
1008         function transform( $params, $flags = 0 ) {
1009                 global $wgThumbnailEpoch;
1010
1011                 do {
1012                         if ( !$this->canRender() ) {
1013                                 $thumb = $this->iconThumb();
1014                                 break; // not a bitmap or renderable image, don't try
1015                         }
1016
1017                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
1018                         $descriptionUrl = $this->getDescriptionUrl();
1019                         if ( $descriptionUrl ) {
1020                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
1021                         }
1022
1023                         $handler = $this->getHandler();
1024                         $script = $this->getTransformScript();
1025                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
1026                                 // Use a script to transform on client request, if possible
1027                                 $thumb = $handler->getScriptedTransform( $this, $script, $params );
1028                                 if ( $thumb ) {
1029                                         break;
1030                                 }
1031                         }
1032
1033                         $normalisedParams = $params;
1034                         $handler->normaliseParams( $this, $normalisedParams );
1035
1036                         $thumbName = $this->thumbName( $normalisedParams );
1037                         $thumbUrl = $this->getThumbUrl( $thumbName );
1038                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1039
1040                         if ( $this->repo ) {
1041                                 // Defer rendering if a 404 handler is set up...
1042                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
1043                                         wfDebug( __METHOD__ . " transformation deferred.\n" );
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                                         break;
1049                                 }
1050                                 // Check if an up-to-date thumbnail already exists...
1051                                 wfDebug( __METHOD__ . ": Doing stat for $thumbPath\n" );
1052                                 if ( !( $flags & self::RENDER_FORCE ) && $this->repo->fileExists( $thumbPath ) ) {
1053                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
1054                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
1055                                                 // XXX: Pass in the storage path even though we are not rendering anything
1056                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
1057                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
1058                                                 $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
1059                                                 $thumb->setStoragePath( $thumbPath );
1060                                                 break;
1061                                         }
1062                                 } elseif ( $flags & self::RENDER_FORCE ) {
1063                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
1064                                 }
1065
1066                                 // If the backend is ready-only, don't keep generating thumbnails
1067                                 // only to return transformation errors, just return the error now.
1068                                 if ( $this->repo->getReadOnlyReason() !== false ) {
1069                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1070                                         break;
1071                                 }
1072                         }
1073
1074                         $tmpFile = $this->makeTransformTmpFile( $thumbPath );
1075
1076                         if ( !$tmpFile ) {
1077                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1078                         } else {
1079                                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1080                         }
1081                 } while ( false );
1082
1083                 return is_object( $thumb ) ? $thumb : false;
1084         }
1085
1086         /**
1087          * Generates a thumbnail according to the given parameters and saves it to storage
1088          * @param TempFSFile $tmpFile Temporary file where the rendered thumbnail will be saved
1089          * @param array $transformParams
1090          * @param int $flags
1091          * @return bool|MediaTransformOutput
1092          */
1093         public function generateAndSaveThumb( $tmpFile, $transformParams, $flags ) {
1094                 global $wgUseSquid, $wgIgnoreImageErrors;
1095
1096                 $handler = $this->getHandler();
1097
1098                 $normalisedParams = $transformParams;
1099                 $handler->normaliseParams( $this, $normalisedParams );
1100
1101                 $thumbName = $this->thumbName( $normalisedParams );
1102                 $thumbUrl = $this->getThumbUrl( $thumbName );
1103                 $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1104
1105                 $tmpThumbPath = $tmpFile->getPath();
1106
1107                 if ( $handler->supportsBucketing() ) {
1108                         $this->generateBucketsIfNeeded( $normalisedParams, $flags );
1109                 }
1110
1111                 // Actually render the thumbnail...
1112                 $thumb = $handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1113                 $tmpFile->bind( $thumb ); // keep alive with $thumb
1114
1115                 if ( !$thumb ) { // bad params?
1116                         $thumb = false;
1117                 } elseif ( $thumb->isError() ) { // transform error
1118                         $this->lastError = $thumb->toText();
1119                         // Ignore errors if requested
1120                         if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
1121                                 $thumb = $handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1122                         }
1123                 } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
1124                         // Copy the thumbnail from the file system into storage...
1125                         $disposition = $this->getThumbDisposition( $thumbName );
1126                         $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
1127                         if ( $status->isOK() ) {
1128                                 $thumb->setStoragePath( $thumbPath );
1129                         } else {
1130                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $transformParams, $flags );
1131                         }
1132                         // Give extensions a chance to do something with this thumbnail...
1133                         Hooks::run( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
1134                 }
1135
1136                 // Purge. Useful in the event of Core -> Squid connection failure or squid
1137                 // purge collisions from elsewhere during failure. Don't keep triggering for
1138                 // "thumbs" which have the main image URL though (bug 13776)
1139                 if ( $wgUseSquid ) {
1140                         if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
1141                                 SquidUpdate::purge( array( $thumbUrl ) );
1142                         }
1143                 }
1144
1145                 return $thumb;
1146         }
1147
1148         /**
1149          * Generates chained bucketed thumbnails if needed
1150          * @param array $params
1151          * @param int $flags
1152          * @return bool Whether at least one bucket was generated
1153          */
1154         protected function generateBucketsIfNeeded( $params, $flags = 0 ) {
1155                 if ( !$this->repo
1156                         || !isset( $params['physicalWidth'] )
1157                         || !isset( $params['physicalHeight'] )
1158                         || !( $bucket = $this->getThumbnailBucket( $params['physicalWidth'] ) )
1159                         || $bucket == $params['physicalWidth'] ) {
1160                         return false;
1161                 }
1162
1163                 $bucketPath = $this->getBucketThumbPath( $bucket );
1164
1165                 if ( $this->repo->fileExists( $bucketPath ) ) {
1166                         return false;
1167                 }
1168
1169                 $params['physicalWidth'] = $bucket;
1170                 $params['width'] = $bucket;
1171
1172                 $params = $this->getHandler()->sanitizeParamsForBucketing( $params );
1173
1174                 $bucketName = $this->getBucketThumbName( $bucket );
1175
1176                 $tmpFile = $this->makeTransformTmpFile( $bucketPath );
1177
1178                 if ( !$tmpFile ) {
1179                         return false;
1180                 }
1181
1182                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1183
1184                 if ( !$thumb || $thumb->isError() ) {
1185                         return false;
1186                 }
1187
1188                 $this->tmpBucketedThumbCache[$bucket] = $tmpFile->getPath();
1189                 // For the caching to work, we need to make the tmp file survive as long as
1190                 // this object exists
1191                 $tmpFile->bind( $this );
1192
1193                 return true;
1194         }
1195
1196         /**
1197          * Returns the most appropriate source image for the thumbnail, given a target thumbnail size
1198          * @param array $params
1199          * @return array Source path and width/height of the source
1200          */
1201         public function getThumbnailSource( $params ) {
1202                 if ( $this->repo
1203                         && $this->getHandler()->supportsBucketing()
1204                         && isset( $params['physicalWidth'] )
1205                         && $bucket = $this->getThumbnailBucket( $params['physicalWidth'] )
1206                 ) {
1207                         if ( $this->getWidth() != 0 ) {
1208                                 $bucketHeight = round( $this->getHeight() * ( $bucket / $this->getWidth() ) );
1209                         } else {
1210                                 $bucketHeight = 0;
1211                         }
1212
1213                         // Try to avoid reading from storage if the file was generated by this script
1214                         if ( isset( $this->tmpBucketedThumbCache[$bucket] ) ) {
1215                                 $tmpPath = $this->tmpBucketedThumbCache[$bucket];
1216
1217                                 if ( file_exists( $tmpPath ) ) {
1218                                         return array(
1219                                                 'path' => $tmpPath,
1220                                                 'width' => $bucket,
1221                                                 'height' => $bucketHeight
1222                                         );
1223                                 }
1224                         }
1225
1226                         $bucketPath = $this->getBucketThumbPath( $bucket );
1227
1228                         if ( $this->repo->fileExists( $bucketPath ) ) {
1229                                 $fsFile = $this->repo->getLocalReference( $bucketPath );
1230
1231                                 if ( $fsFile ) {
1232                                         return array(
1233                                                 'path' => $fsFile->getPath(),
1234                                                 'width' => $bucket,
1235                                                 'height' => $bucketHeight
1236                                         );
1237                                 }
1238                         }
1239                 }
1240
1241                 // Thumbnailing a very large file could result in network saturation if
1242                 // everyone does it at once.
1243                 if ( $this->getSize() >= 1e7 ) { // 10MB
1244                         $that = $this;
1245                         $work = new PoolCounterWorkViaCallback( 'GetLocalFileCopy', sha1( $this->getName() ),
1246                                 array(
1247                                         'doWork' => function () use ( $that ) {
1248                                                 return $that->getLocalRefPath();
1249                                         }
1250                                 )
1251                         );
1252                         $srcPath = $work->execute();
1253                 } else {
1254                         $srcPath = $this->getLocalRefPath();
1255                 }
1256
1257                 // Original file
1258                 return array(
1259                         'path' => $srcPath,
1260                         'width' => $this->getWidth(),
1261                         'height' => $this->getHeight()
1262                 );
1263         }
1264
1265         /**
1266          * Returns the repo path of the thumb for a given bucket
1267          * @param int $bucket
1268          * @return string
1269          */
1270         protected function getBucketThumbPath( $bucket ) {
1271                 $thumbName = $this->getBucketThumbName( $bucket );
1272                 return $this->getThumbPath( $thumbName );
1273         }
1274
1275         /**
1276          * Returns the name of the thumb for a given bucket
1277          * @param int $bucket
1278          * @return string
1279          */
1280         protected function getBucketThumbName( $bucket ) {
1281                 return $this->thumbName( array( 'physicalWidth' => $bucket ) );
1282         }
1283
1284         /**
1285          * Creates a temp FS file with the same extension and the thumbnail
1286          * @param string $thumbPath Thumbnail path
1287          * @return TempFSFile
1288          */
1289         protected function makeTransformTmpFile( $thumbPath ) {
1290                 $thumbExt = FileBackend::extensionFromPath( $thumbPath );
1291                 return TempFSFile::factory( 'transform_', $thumbExt );
1292         }
1293
1294         /**
1295          * @param string $thumbName Thumbnail name
1296          * @param string $dispositionType Type of disposition (either "attachment" or "inline")
1297          * @return string Content-Disposition header value
1298          */
1299         function getThumbDisposition( $thumbName, $dispositionType = 'inline' ) {
1300                 $fileName = $this->name; // file name to suggest
1301                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
1302                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
1303                         $fileName .= ".$thumbExt";
1304                 }
1305
1306                 return FileBackend::makeContentDisposition( $dispositionType, $fileName );
1307         }
1308
1309         /**
1310          * Hook into transform() to allow migration of thumbnail files
1311          * STUB
1312          * Overridden by LocalFile
1313          * @param string $thumbName
1314          */
1315         function migrateThumbFile( $thumbName ) {
1316         }
1317
1318         /**
1319          * Get a MediaHandler instance for this file
1320          *
1321          * @return MediaHandler|bool Registered MediaHandler for file's MIME type
1322          *   or false if none found
1323          */
1324         function getHandler() {
1325                 if ( !isset( $this->handler ) ) {
1326                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1327                 }
1328
1329                 return $this->handler;
1330         }
1331
1332         /**
1333          * Get a ThumbnailImage representing a file type icon
1334          *
1335          * @return ThumbnailImage
1336          */
1337         function iconThumb() {
1338                 global $wgResourceBasePath, $IP;
1339                 $assetsPath = "$wgResourceBasePath/resources/assets/file-type-icons/";
1340                 $assetsDirectory = "$IP/resources/assets/file-type-icons/";
1341
1342                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1343                 foreach ( $try as $icon ) {
1344                         if ( file_exists( $assetsDirectory . $icon ) ) { // always FS
1345                                 $params = array( 'width' => 120, 'height' => 120 );
1346
1347                                 return new ThumbnailImage( $this, $assetsPath . $icon, false, $params );
1348                         }
1349                 }
1350
1351                 return null;
1352         }
1353
1354         /**
1355          * Get last thumbnailing error.
1356          * Largely obsolete.
1357          * @return string
1358          */
1359         function getLastError() {
1360                 return $this->lastError;
1361         }
1362
1363         /**
1364          * Get all thumbnail names previously generated for this file
1365          * STUB
1366          * Overridden by LocalFile
1367          * @return array
1368          */
1369         function getThumbnails() {
1370                 return array();
1371         }
1372
1373         /**
1374          * Purge shared caches such as thumbnails and DB data caching
1375          * STUB
1376          * Overridden by LocalFile
1377          * @param array $options Options, which include:
1378          *   'forThumbRefresh' : The purging is only to refresh thumbnails
1379          */
1380         function purgeCache( $options = array() ) {
1381         }
1382
1383         /**
1384          * Purge the file description page, but don't go after
1385          * pages using the file. Use when modifying file history
1386          * but not the current data.
1387          */
1388         function purgeDescription() {
1389                 $title = $this->getTitle();
1390                 if ( $title ) {
1391                         $title->invalidateCache();
1392                         $title->purgeSquid();
1393                 }
1394         }
1395
1396         /**
1397          * Purge metadata and all affected pages when the file is created,
1398          * deleted, or majorly updated.
1399          */
1400         function purgeEverything() {
1401                 // Delete thumbnails and refresh file metadata cache
1402                 $this->purgeCache();
1403                 $this->purgeDescription();
1404
1405                 // Purge cache of all pages using this file
1406                 $title = $this->getTitle();
1407                 if ( $title ) {
1408                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1409                         $update->doUpdate();
1410                 }
1411         }
1412
1413         /**
1414          * Return a fragment of the history of file.
1415          *
1416          * STUB
1417          * @param int $limit Limit of rows to return
1418          * @param string $start Only revisions older than $start will be returned
1419          * @param string $end Only revisions newer than $end will be returned
1420          * @param bool $inc Include the endpoints of the time range
1421          *
1422          * @return array
1423          */
1424         function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
1425                 return array();
1426         }
1427
1428         /**
1429          * Return the history of this file, line by line. Starts with current version,
1430          * then old versions. Should return an object similar to an image/oldimage
1431          * database row.
1432          *
1433          * STUB
1434          * Overridden in LocalFile
1435          * @return bool
1436          */
1437         public function nextHistoryLine() {
1438                 return false;
1439         }
1440
1441         /**
1442          * Reset the history pointer to the first element of the history.
1443          * Always call this function after using nextHistoryLine() to free db resources
1444          * STUB
1445          * Overridden in LocalFile.
1446          */
1447         public function resetHistory() {
1448         }
1449
1450         /**
1451          * Get the filename hash component of the directory including trailing slash,
1452          * e.g. f/fa/
1453          * If the repository is not hashed, returns an empty string.
1454          *
1455          * @return string
1456          */
1457         function getHashPath() {
1458                 if ( !isset( $this->hashPath ) ) {
1459                         $this->assertRepoDefined();
1460                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1461                 }
1462
1463                 return $this->hashPath;
1464         }
1465
1466         /**
1467          * Get the path of the file relative to the public zone root.
1468          * This function is overridden in OldLocalFile to be like getArchiveRel().
1469          *
1470          * @return string
1471          */
1472         function getRel() {
1473                 return $this->getHashPath() . $this->getName();
1474         }
1475
1476         /**
1477          * Get the path of an archived file relative to the public zone root
1478          *
1479          * @param bool|string $suffix If not false, the name of an archived thumbnail file
1480          *
1481          * @return string
1482          */
1483         function getArchiveRel( $suffix = false ) {
1484                 $path = 'archive/' . $this->getHashPath();
1485                 if ( $suffix === false ) {
1486                         $path = substr( $path, 0, -1 );
1487                 } else {
1488                         $path .= $suffix;
1489                 }
1490
1491                 return $path;
1492         }
1493
1494         /**
1495          * Get the path, relative to the thumbnail zone root, of the
1496          * thumbnail directory or a particular file if $suffix is specified
1497          *
1498          * @param bool|string $suffix If not false, the name of a thumbnail file
1499          * @return string
1500          */
1501         function getThumbRel( $suffix = false ) {
1502                 $path = $this->getRel();
1503                 if ( $suffix !== false ) {
1504                         $path .= '/' . $suffix;
1505                 }
1506
1507                 return $path;
1508         }
1509
1510         /**
1511          * Get urlencoded path of the file relative to the public zone root.
1512          * This function is overridden in OldLocalFile to be like getArchiveUrl().
1513          *
1514          * @return string
1515          */
1516         function getUrlRel() {
1517                 return $this->getHashPath() . rawurlencode( $this->getName() );
1518         }
1519
1520         /**
1521          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1522          * or a specific thumb if the $suffix is given.
1523          *
1524          * @param string $archiveName The timestamped name of an archived image
1525          * @param bool|string $suffix If not false, the name of a thumbnail file
1526          * @return string
1527          */
1528         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1529                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1530                 if ( $suffix === false ) {
1531                         $path = substr( $path, 0, -1 );
1532                 } else {
1533                         $path .= $suffix;
1534                 }
1535
1536                 return $path;
1537         }
1538
1539         /**
1540          * Get the path of the archived file.
1541          *
1542          * @param bool|string $suffix If not false, the name of an archived file.
1543          * @return string
1544          */
1545         function getArchivePath( $suffix = false ) {
1546                 $this->assertRepoDefined();
1547
1548                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1549         }
1550
1551         /**
1552          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1553          *
1554          * @param string $archiveName The timestamped name of an archived image
1555          * @param bool|string $suffix If not false, the name of a thumbnail file
1556          * @return string
1557          */
1558         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1559                 $this->assertRepoDefined();
1560
1561                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1562                 $this->getArchiveThumbRel( $archiveName, $suffix );
1563         }
1564
1565         /**
1566          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1567          *
1568          * @param bool|string $suffix If not false, the name of a thumbnail file
1569          * @return string
1570          */
1571         function getThumbPath( $suffix = false ) {
1572                 $this->assertRepoDefined();
1573
1574                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1575         }
1576
1577         /**
1578          * Get the path of the transcoded directory, or a particular file if $suffix is specified
1579          *
1580          * @param bool|string $suffix If not false, the name of a media file
1581          * @return string
1582          */
1583         function getTranscodedPath( $suffix = false ) {
1584                 $this->assertRepoDefined();
1585
1586                 return $this->repo->getZonePath( 'transcoded' ) . '/' . $this->getThumbRel( $suffix );
1587         }
1588
1589         /**
1590          * Get the URL of the archive directory, or a particular file if $suffix is specified
1591          *
1592          * @param bool|string $suffix If not false, the name of an archived file
1593          * @return string
1594          */
1595         function getArchiveUrl( $suffix = false ) {
1596                 $this->assertRepoDefined();
1597                 $ext = $this->getExtension();
1598                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1599                 if ( $suffix === false ) {
1600                         $path = substr( $path, 0, -1 );
1601                 } else {
1602                         $path .= rawurlencode( $suffix );
1603                 }
1604
1605                 return $path;
1606         }
1607
1608         /**
1609          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1610          *
1611          * @param string $archiveName The timestamped name of an archived image
1612          * @param bool|string $suffix If not false, the name of a thumbnail file
1613          * @return string
1614          */
1615         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1616                 $this->assertRepoDefined();
1617                 $ext = $this->getExtension();
1618                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1619                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1620                 if ( $suffix === false ) {
1621                         $path = substr( $path, 0, -1 );
1622                 } else {
1623                         $path .= rawurlencode( $suffix );
1624                 }
1625
1626                 return $path;
1627         }
1628
1629         /**
1630          * Get the URL of the zone directory, or a particular file if $suffix is specified
1631          *
1632          * @param string $zone Name of requested zone
1633          * @param bool|string $suffix If not false, the name of a file in zone
1634          * @return string Path
1635          */
1636         function getZoneUrl( $zone, $suffix = false ) {
1637                 $this->assertRepoDefined();
1638                 $ext = $this->getExtension();
1639                 $path = $this->repo->getZoneUrl( $zone, $ext ) . '/' . $this->getUrlRel();
1640                 if ( $suffix !== false ) {
1641                         $path .= '/' . rawurlencode( $suffix );
1642                 }
1643
1644                 return $path;
1645         }
1646
1647         /**
1648          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1649          *
1650          * @param bool|string $suffix If not false, the name of a thumbnail file
1651          * @return string Path
1652          */
1653         function getThumbUrl( $suffix = false ) {
1654                 return $this->getZoneUrl( 'thumb', $suffix );
1655         }
1656
1657         /**
1658          * Get the URL of the transcoded directory, or a particular file if $suffix is specified
1659          *
1660          * @param bool|string $suffix If not false, the name of a media file
1661          * @return string Path
1662          */
1663         function getTranscodedUrl( $suffix = false ) {
1664                 return $this->getZoneUrl( 'transcoded', $suffix );
1665         }
1666
1667         /**
1668          * Get the public zone virtual URL for a current version source file
1669          *
1670          * @param bool|string $suffix If not false, the name of a thumbnail file
1671          * @return string
1672          */
1673         function getVirtualUrl( $suffix = false ) {
1674                 $this->assertRepoDefined();
1675                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1676                 if ( $suffix !== false ) {
1677                         $path .= '/' . rawurlencode( $suffix );
1678                 }
1679
1680                 return $path;
1681         }
1682
1683         /**
1684          * Get the public zone virtual URL for an archived version source file
1685          *
1686          * @param bool|string $suffix If not false, the name of a thumbnail file
1687          * @return string
1688          */
1689         function getArchiveVirtualUrl( $suffix = false ) {
1690                 $this->assertRepoDefined();
1691                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1692                 if ( $suffix === false ) {
1693                         $path = substr( $path, 0, -1 );
1694                 } else {
1695                         $path .= rawurlencode( $suffix );
1696                 }
1697
1698                 return $path;
1699         }
1700
1701         /**
1702          * Get the virtual URL for a thumbnail file or directory
1703          *
1704          * @param bool|string $suffix If not false, the name of a thumbnail file
1705          * @return string
1706          */
1707         function getThumbVirtualUrl( $suffix = false ) {
1708                 $this->assertRepoDefined();
1709                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1710                 if ( $suffix !== false ) {
1711                         $path .= '/' . rawurlencode( $suffix );
1712                 }
1713
1714                 return $path;
1715         }
1716
1717         /**
1718          * @return bool
1719          */
1720         function isHashed() {
1721                 $this->assertRepoDefined();
1722
1723                 return (bool)$this->repo->getHashLevels();
1724         }
1725
1726         /**
1727          * @throws MWException
1728          */
1729         function readOnlyError() {
1730                 throw new MWException( get_class( $this ) . ': write operations are not supported' );
1731         }
1732
1733         /**
1734          * Record a file upload in the upload log and the image table
1735          * STUB
1736          * Overridden by LocalFile
1737          * @param string $oldver
1738          * @param string $desc
1739          * @param string $license
1740          * @param string $copyStatus
1741          * @param string $source
1742          * @param bool $watch
1743          * @param string|bool $timestamp
1744          * @param null|User $user User object or null to use $wgUser
1745          * @return bool
1746          * @throws MWException
1747          */
1748         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
1749                 $watch = false, $timestamp = false, User $user = null
1750         ) {
1751                 $this->readOnlyError();
1752         }
1753
1754         /**
1755          * Move or copy a file to its public location. If a file exists at the
1756          * destination, move it to an archive. Returns a FileRepoStatus object with
1757          * the archive name in the "value" member on success.
1758          *
1759          * The archive name should be passed through to recordUpload for database
1760          * registration.
1761          *
1762          * Options to $options include:
1763          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1764          *
1765          * @param string $srcPath Local filesystem path to the source image
1766          * @param int $flags A bitwise combination of:
1767          *   File::DELETE_SOURCE    Delete the source file, i.e. move rather than copy
1768          * @param array $options Optional additional parameters
1769          * @return FileRepoStatus On success, the value member contains the
1770          *   archive name, or an empty string if it was a new file.
1771          *
1772          * STUB
1773          * Overridden by LocalFile
1774          */
1775         function publish( $srcPath, $flags = 0, array $options = array() ) {
1776                 $this->readOnlyError();
1777         }
1778
1779         /**
1780          * @param bool|IContextSource $context Context to use (optional)
1781          * @return bool
1782          */
1783         function formatMetadata( $context = false ) {
1784                 if ( !$this->getHandler() ) {
1785                         return false;
1786                 }
1787
1788                 return $this->getHandler()->formatMetadata( $this, $context );
1789         }
1790
1791         /**
1792          * Returns true if the file comes from the local file repository.
1793          *
1794          * @return bool
1795          */
1796         function isLocal() {
1797                 return $this->repo && $this->repo->isLocal();
1798         }
1799
1800         /**
1801          * Returns the name of the repository.
1802          *
1803          * @return string
1804          */
1805         function getRepoName() {
1806                 return $this->repo ? $this->repo->getName() : 'unknown';
1807         }
1808
1809         /**
1810          * Returns the repository
1811          *
1812          * @return FileRepo|LocalRepo|bool
1813          */
1814         function getRepo() {
1815                 return $this->repo;
1816         }
1817
1818         /**
1819          * Returns true if the image is an old version
1820          * STUB
1821          *
1822          * @return bool
1823          */
1824         function isOld() {
1825                 return false;
1826         }
1827
1828         /**
1829          * Is this file a "deleted" file in a private archive?
1830          * STUB
1831          *
1832          * @param int $field One of DELETED_* bitfield constants
1833          * @return bool
1834          */
1835         function isDeleted( $field ) {
1836                 return false;
1837         }
1838
1839         /**
1840          * Return the deletion bitfield
1841          * STUB
1842          * @return int
1843          */
1844         function getVisibility() {
1845                 return 0;
1846         }
1847
1848         /**
1849          * Was this file ever deleted from the wiki?
1850          *
1851          * @return bool
1852          */
1853         function wasDeleted() {
1854                 $title = $this->getTitle();
1855
1856                 return $title && $title->isDeletedQuick();
1857         }
1858
1859         /**
1860          * Move file to the new title
1861          *
1862          * Move current, old version and all thumbnails
1863          * to the new filename. Old file is deleted.
1864          *
1865          * Cache purging is done; checks for validity
1866          * and logging are caller's responsibility
1867          *
1868          * @param Title $target New file name
1869          * @return FileRepoStatus
1870          */
1871         function move( $target ) {
1872                 $this->readOnlyError();
1873         }
1874
1875         /**
1876          * Delete all versions of the file.
1877          *
1878          * Moves the files into an archive directory (or deletes them)
1879          * and removes the database rows.
1880          *
1881          * Cache purging is done; logging is caller's responsibility.
1882          *
1883          * @param string $reason
1884          * @param bool $suppress Hide content from sysops?
1885          * @param User|null $user
1886          * @return bool Boolean on success, false on some kind of failure
1887          * STUB
1888          * Overridden by LocalFile
1889          */
1890         function delete( $reason, $suppress = false, $user = null ) {
1891                 $this->readOnlyError();
1892         }
1893
1894         /**
1895          * Restore all or specified deleted revisions to the given file.
1896          * Permissions and logging are left to the caller.
1897          *
1898          * May throw database exceptions on error.
1899          *
1900          * @param array $versions Set of record ids of deleted items to restore,
1901          *   or empty to restore all revisions.
1902          * @param bool $unsuppress Remove restrictions on content upon restoration?
1903          * @return int|bool The number of file revisions restored if successful,
1904          *   or false on failure
1905          * STUB
1906          * Overridden by LocalFile
1907          */
1908         function restore( $versions = array(), $unsuppress = false ) {
1909                 $this->readOnlyError();
1910         }
1911
1912         /**
1913          * Returns 'true' if this file is a type which supports multiple pages,
1914          * e.g. DJVU or PDF. Note that this may be true even if the file in
1915          * question only has a single page.
1916          *
1917          * @return bool
1918          */
1919         function isMultipage() {
1920                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1921         }
1922
1923         /**
1924          * Returns the number of pages of a multipage document, or false for
1925          * documents which aren't multipage documents
1926          *
1927          * @return bool|int
1928          */
1929         function pageCount() {
1930                 if ( !isset( $this->pageCount ) ) {
1931                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1932                                 $this->pageCount = $this->handler->pageCount( $this );
1933                         } else {
1934                                 $this->pageCount = false;
1935                         }
1936                 }
1937
1938                 return $this->pageCount;
1939         }
1940
1941         /**
1942          * Calculate the height of a thumbnail using the source and destination width
1943          *
1944          * @param int $srcWidth
1945          * @param int $srcHeight
1946          * @param int $dstWidth
1947          *
1948          * @return int
1949          */
1950         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1951                 // Exact integer multiply followed by division
1952                 if ( $srcWidth == 0 ) {
1953                         return 0;
1954                 } else {
1955                         return round( $srcHeight * $dstWidth / $srcWidth );
1956                 }
1957         }
1958
1959         /**
1960          * Get an image size array like that returned by getImageSize(), or false if it
1961          * can't be determined. Loads the image size directly from the file ignoring caches.
1962          *
1963          * @note Use getWidth()/getHeight() instead of this method unless you have a
1964          *  a good reason. This method skips all caches.
1965          *
1966          * @param string $filePath The path to the file (e.g. From getLocalPathRef() )
1967          * @return array The width, followed by height, with optionally more things after
1968          */
1969         function getImageSize( $filePath ) {
1970                 if ( !$this->getHandler() ) {
1971                         return false;
1972                 }
1973
1974                 return $this->getHandler()->getImageSize( $this, $filePath );
1975         }
1976
1977         /**
1978          * Get the URL of the image description page. May return false if it is
1979          * unknown or not applicable.
1980          *
1981          * @return string
1982          */
1983         function getDescriptionUrl() {
1984                 if ( $this->repo ) {
1985                         return $this->repo->getDescriptionUrl( $this->getName() );
1986                 } else {
1987                         return false;
1988                 }
1989         }
1990
1991         /**
1992          * Get the HTML text of the description page, if available
1993          *
1994          * @param bool|Language $lang Optional language to fetch description in
1995          * @return string
1996          */
1997         function getDescriptionText( $lang = false ) {
1998                 global $wgMemc, $wgLang;
1999                 if ( !$this->repo || !$this->repo->fetchDescription ) {
2000                         return false;
2001                 }
2002                 if ( !$lang ) {
2003                         $lang = $wgLang;
2004                 }
2005                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $lang->getCode() );
2006                 if ( $renderUrl ) {
2007                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
2008                                 wfDebug( "Attempting to get the description from cache..." );
2009                                 $key = $this->repo->getLocalCacheKey(
2010                                         'RemoteFileDescription',
2011                                         'url',
2012                                         $lang->getCode(),
2013                                         $this->getName()
2014                                 );
2015                                 $obj = $wgMemc->get( $key );
2016                                 if ( $obj ) {
2017                                         wfDebug( "success!\n" );
2018
2019                                         return $obj;
2020                                 }
2021                                 wfDebug( "miss\n" );
2022                         }
2023                         wfDebug( "Fetching shared description from $renderUrl\n" );
2024                         $res = Http::get( $renderUrl, array(), __METHOD__ );
2025                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
2026                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
2027                         }
2028
2029                         return $res;
2030                 } else {
2031                         return false;
2032                 }
2033         }
2034
2035         /**
2036          * Get description of file revision
2037          * STUB
2038          *
2039          * @param int $audience One of:
2040          *   File::FOR_PUBLIC       to be displayed to all users
2041          *   File::FOR_THIS_USER    to be displayed to the given user
2042          *   File::RAW              get the description regardless of permissions
2043          * @param User $user User object to check for, only if FOR_THIS_USER is
2044          *   passed to the $audience parameter
2045          * @return string
2046          */
2047         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
2048                 return null;
2049         }
2050
2051         /**
2052          * Get the 14-character timestamp of the file upload
2053          *
2054          * @return string|bool TS_MW timestamp or false on failure
2055          */
2056         function getTimestamp() {
2057                 $this->assertRepoDefined();
2058
2059                 return $this->repo->getFileTimestamp( $this->getPath() );
2060         }
2061
2062         /**
2063          * Returns the timestamp (in TS_MW format) of the last change of the description page.
2064          * Returns false if the file does not have a description page, or retrieving the timestamp
2065          * would be expensive.
2066          * @since 1.25
2067          * @return string|bool
2068          */
2069         public function getDescriptionTouched() {
2070                 return false;
2071         }
2072
2073         /**
2074          * Get the SHA-1 base 36 hash of the file
2075          *
2076          * @return string
2077          */
2078         function getSha1() {
2079                 $this->assertRepoDefined();
2080
2081                 return $this->repo->getFileSha1( $this->getPath() );
2082         }
2083
2084         /**
2085          * Get the deletion archive key, "<sha1>.<ext>"
2086          *
2087          * @return string
2088          */
2089         function getStorageKey() {
2090                 $hash = $this->getSha1();
2091                 if ( !$hash ) {
2092                         return false;
2093                 }
2094                 $ext = $this->getExtension();
2095                 $dotExt = $ext === '' ? '' : ".$ext";
2096
2097                 return $hash . $dotExt;
2098         }
2099
2100         /**
2101          * Determine if the current user is allowed to view a particular
2102          * field of this file, if it's marked as deleted.
2103          * STUB
2104          * @param int $field
2105          * @param User $user User object to check, or null to use $wgUser
2106          * @return bool
2107          */
2108         function userCan( $field, User $user = null ) {
2109                 return true;
2110         }
2111
2112         /**
2113          * @return array HTTP header name/value map to use for HEAD/GET request responses
2114          */
2115         function getStreamHeaders() {
2116                 $handler = $this->getHandler();
2117                 if ( $handler ) {
2118                         return $handler->getStreamHeaders( $this->getMetadata() );
2119                 } else {
2120                         return array();
2121                 }
2122         }
2123
2124         /**
2125          * @return string
2126          */
2127         function getLongDesc() {
2128                 $handler = $this->getHandler();
2129                 if ( $handler ) {
2130                         return $handler->getLongDesc( $this );
2131                 } else {
2132                         return MediaHandler::getGeneralLongDesc( $this );
2133                 }
2134         }
2135
2136         /**
2137          * @return string
2138          */
2139         function getShortDesc() {
2140                 $handler = $this->getHandler();
2141                 if ( $handler ) {
2142                         return $handler->getShortDesc( $this );
2143                 } else {
2144                         return MediaHandler::getGeneralShortDesc( $this );
2145                 }
2146         }
2147
2148         /**
2149          * @return string
2150          */
2151         function getDimensionsString() {
2152                 $handler = $this->getHandler();
2153                 if ( $handler ) {
2154                         return $handler->getDimensionsString( $this );
2155                 } else {
2156                         return '';
2157                 }
2158         }
2159
2160         /**
2161          * @return string
2162          */
2163         function getRedirected() {
2164                 return $this->redirected;
2165         }
2166
2167         /**
2168          * @return Title|null
2169          */
2170         function getRedirectedTitle() {
2171                 if ( $this->redirected ) {
2172                         if ( !$this->redirectTitle ) {
2173                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
2174                         }
2175
2176                         return $this->redirectTitle;
2177                 }
2178
2179                 return null;
2180         }
2181
2182         /**
2183          * @param string $from
2184          * @return void
2185          */
2186         function redirectedFrom( $from ) {
2187                 $this->redirected = $from;
2188         }
2189
2190         /**
2191          * @return bool
2192          */
2193         function isMissing() {
2194                 return false;
2195         }
2196
2197         /**
2198          * Check if this file object is small and can be cached
2199          * @return bool
2200          */
2201         public function isCacheable() {
2202                 return true;
2203         }
2204
2205         /**
2206          * Assert that $this->repo is set to a valid FileRepo instance
2207          * @throws MWException
2208          */
2209         protected function assertRepoDefined() {
2210                 if ( !( $this->repo instanceof $this->repoClass ) ) {
2211                         throw new MWException( "A {$this->repoClass} object is not set for this File.\n" );
2212                 }
2213         }
2214
2215         /**
2216          * Assert that $this->title is set to a Title
2217          * @throws MWException
2218          */
2219         protected function assertTitleDefined() {
2220                 if ( !( $this->title instanceof Title ) ) {
2221                         throw new MWException( "A Title object is not set for this File.\n" );
2222                 }
2223         }
2224
2225         /**
2226          * True if creating thumbnails from the file is large or otherwise resource-intensive.
2227          * @return bool
2228          */
2229         public function isExpensiveToThumbnail() {
2230                 $handler = $this->getHandler();
2231                 return $handler ? $handler->isExpensiveToThumbnail( $this ) : false;
2232         }
2233 }