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                 // Some subclasses do not use $title, but set name/title some other way
 167                 if ( $title !== false ) {
 168                         $title = self::normalizeTitle( $title, 'exception' );
 169                 }
 170                 $this->title = $title;
 171                 $this->repo = $repo;
 172         }
 173
 174         /**
 175          * Given a string or Title object return either a
 176          * valid Title object with namespace NS_FILE or null
 177          *
 178          * @param Title|string $title
 179          * @param string|bool $exception Use 'exception' to throw an error on bad titles
 180          * @throws MWException
 181          * @return Title|null
 182          */
 183         static function normalizeTitle( $title, $exception = false ) {
 184                 $ret = $title;
 185                 if ( $ret instanceof Title ) {
 186                         # Normalize NS_MEDIA -> NS_FILE
 187                         if ( $ret->getNamespace() == NS_MEDIA ) {
 188                                 $ret = Title::makeTitleSafe( NS_FILE, $ret->getDBkey() );
 189                         # Sanity check the title namespace
 190                         } elseif ( $ret->getNamespace() !== NS_FILE ) {
 191                                 $ret = null;
 192                         }
 193                 } else {
 194                         # Convert strings to Title objects
 195                         $ret = Title::makeTitleSafe( NS_FILE, (string)$ret );
 196                 }
 197                 if ( !$ret && $exception !== false ) {
 198                         throw new MWException( "`$title` is not a valid file title." );
 199                 }
 200
 201                 return $ret;
 202         }
 203
 204         function __get( $name ) {
 205                 $function = array( $this, 'get' . ucfirst( $name ) );
 206                 if ( !is_callable( $function ) ) {
 207                         return null;
 208                 } else {
 209                         $this->$name = call_user_func( $function );
 210
 211                         return $this->$name;
 212                 }
 213         }
 214
 215         /**
 216          * Normalize a file extension to the common form, and ensure it's clean.
 217          * Extensions with non-alphanumeric characters will be discarded.
 218          *
 219          * @param string $ext (without the .)
 220          * @return string
 221          */
 222         static function normalizeExtension( $ext ) {
 223                 $lower = strtolower( $ext );
 224                 $squish = array(
 225                         'htm' => 'html',
 226                         'jpeg' => 'jpg',
 227                         'mpeg' => 'mpg',
 228                         'tiff' => 'tif',
 229                         'ogv' => 'ogg' );
 230                 if ( isset( $squish[$lower] ) ) {
 231                         return $squish[$lower];
 232                 } elseif ( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 233                         return $lower;
 234                 } else {
 235                         return '';
 236                 }
 237         }
 238
 239         /**
 240          * Checks if file extensions are compatible
 241          *
 242          * @param File $old Old file
 243          * @param string $new New name
 244          *
 245          * @return bool|null
 246          */
 247         static function checkExtensionCompatibility( File $old, $new ) {
 248                 $oldMime = $old->getMimeType();
 249                 $n = strrpos( $new, '.' );
 250                 $newExt = self::normalizeExtension( $n ? substr( $new, $n + 1 ) : '' );
 251                 $mimeMagic = MimeMagic::singleton();
 252
 253                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 254         }
 255
 256         /**
 257          * Upgrade the database row if there is one
 258          * Called by ImagePage
 259          * STUB
 260          */
 261         function upgradeRow() {
 262         }
 263
 264         /**
 265          * Split an internet media type into its two components; if not
 266          * a two-part name, set the minor type to 'unknown'.
 267          *
 268          * @param string $mime "text/html" etc
 269          * @return array ("text", "html") etc
 270          */
 271         public static function splitMime( $mime ) {
 272                 if ( strpos( $mime, '/' ) !== false ) {
 273                         return explode( '/', $mime, 2 );
 274                 } else {
 275                         return array( $mime, 'unknown' );
 276                 }
 277         }
 278
 279         /**
 280          * Callback for usort() to do file sorts by name
 281          *
 282          * @param File $a
 283          * @param File $b
 284          * @return int Result of name comparison
 285          */
 286         public static function compare( File $a, File $b ) {
 287                 return strcmp( $a->getName(), $b->getName() );
 288         }
 289
 290         /**
 291          * Return the name of this file
 292          *
 293          * @return string
 294          */
 295         public function getName() {
 296                 if ( !isset( $this->name ) ) {
 297                         $this->assertRepoDefined();
 298                         $this->name = $this->repo->getNameFromTitle( $this->title );
 299                 }
 300
 301                 return $this->name;
 302         }
 303
 304         /**
 305          * Get the file extension, e.g. "svg"
 306          *
 307          * @return string
 308          */
 309         function getExtension() {
 310                 if ( !isset( $this->extension ) ) {
 311                         $n = strrpos( $this->getName(), '.' );
 312                         $this->extension = self::normalizeExtension(
 313                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 314                 }
 315
 316                 return $this->extension;
 317         }
 318
 319         /**
 320          * Return the associated title object
 321          *
 322          * @return Title
 323          */
 324         public function getTitle() {
 325                 return $this->title;
 326         }
 327
 328         /**
 329          * Return the title used to find this file
 330          *
 331          * @return Title
 332          */
 333         public function getOriginalTitle() {
 334                 if ( $this->redirected ) {
 335                         return $this->getRedirectedTitle();
 336                 }
 337
 338                 return $this->title;
 339         }
 340
 341         /**
 342          * Return the URL of the file
 343          *
 344          * @return string
 345          */
 346         public function getUrl() {
 347                 if ( !isset( $this->url ) ) {
 348                         $this->assertRepoDefined();
 349                         $ext = $this->getExtension();
 350                         $this->url = $this->repo->getZoneUrl( 'public', $ext ) . '/' . $this->getUrlRel();
 351                 }
 352
 353                 return $this->url;
 354         }
 355
 356         /**
 357          * Return a fully-qualified URL to the file.
 358          * Upload URL paths _may or may not_ be fully qualified, so
 359          * we check. Local paths are assumed to belong on $wgServer.
 360          *
 361          * @return string
 362          */
 363         public function getFullUrl() {
 364                 return wfExpandUrl( $this->getUrl(), PROTO_RELATIVE );
 365         }
 366
 367         /**
 368          * @return string
 369          */
 370         public function getCanonicalUrl() {
 371                 return wfExpandUrl( $this->getUrl(), PROTO_CANONICAL );
 372         }
 373
 374         /**
 375          * @return string
 376          */
 377         function getViewURL() {
 378                 if ( $this->mustRender() ) {
 379                         if ( $this->canRender() ) {
 380                                 return $this->createThumb( $this->getWidth() );
 381                         } else {
 382                                 wfDebug( __METHOD__ . ': supposed to render ' . $this->getName() .
 383                                         ' (' . $this->getMimeType() . "), but can't!\n" );
 384
 385                                 return $this->getURL(); #hm... return NULL?
 386                         }
 387                 } else {
 388                         return $this->getURL();
 389                 }
 390         }
 391
 392         /**
 393          * Return the storage path to the file. Note that this does
 394          * not mean that a file actually exists under that location.
 395          *
 396          * This path depends on whether directory hashing is active or not,
 397          * i.e. whether the files are all found in the same directory,
 398          * or in hashed paths like /images/3/3c.
 399          *
 400          * Most callers don't check the return value, but ForeignAPIFile::getPath
 401          * returns false.
 402          *
 403          * @return string|bool ForeignAPIFile::getPath can return false
 404          */
 405         public function getPath() {
 406                 if ( !isset( $this->path ) ) {
 407                         $this->assertRepoDefined();
 408                         $this->path = $this->repo->getZonePath( 'public' ) . '/' . $this->getRel();
 409                 }
 410
 411                 return $this->path;
 412         }
 413
 414         /**
 415          * Get an FS copy or original of this file and return the path.
 416          * Returns false on failure. Callers must not alter the file.
 417          * Temporary files are cleared automatically.
 418          *
 419          * @return string|bool False on failure
 420          */
 421         public function getLocalRefPath() {
 422                 $this->assertRepoDefined();
 423                 if ( !isset( $this->fsFile ) ) {
 424                         $this->fsFile = $this->repo->getLocalReference( $this->getPath() );
 425                         if ( !$this->fsFile ) {
 426                                 $this->fsFile = false; // null => false; cache negative hits
 427                         }
 428                 }
 429
 430                 return ( $this->fsFile )
 431                         ? $this->fsFile->getPath()
 432                         : false;
 433         }
 434
 435         /**
 436          * Return the width of the image. Returns false if the width is unknown
 437          * or undefined.
 438          *
 439          * STUB
 440          * Overridden by LocalFile, UnregisteredLocalFile
 441          *
 442          * @param int $page
 443          * @return int|bool
 444          */
 445         public function getWidth( $page = 1 ) {
 446                 return false;
 447         }
 448
 449         /**
 450          * Return the height of the image. Returns false if the height is unknown
 451          * or undefined
 452          *
 453          * STUB
 454          * Overridden by LocalFile, UnregisteredLocalFile
 455          *
 456          * @param int $page
 457          * @return bool|int False on failure
 458          */
 459         public function getHeight( $page = 1 ) {
 460                 return false;
 461         }
 462
 463         /**
 464          * Return the smallest bucket from $wgThumbnailBuckets which is at least
 465          * $wgThumbnailMinimumBucketDistance larger than $desiredWidth. The returned bucket, if any,
 466          * will always be bigger than $desiredWidth.
 467          *
 468          * @param int $desiredWidth
 469          * @param int $page
 470          * @return bool|int
 471          */
 472         public function getThumbnailBucket( $desiredWidth, $page = 1 ) {
 473                 global $wgThumbnailBuckets, $wgThumbnailMinimumBucketDistance;
 474
 475                 $imageWidth = $this->getWidth( $page );
 476
 477                 if ( $imageWidth === false ) {
 478                         return false;
 479                 }
 480
 481                 if ( $desiredWidth > $imageWidth ) {
 482                         return false;
 483                 }
 484
 485                 if ( !$wgThumbnailBuckets ) {
 486                         return false;
 487                 }
 488
 489                 $sortedBuckets = $wgThumbnailBuckets;
 490
 491                 sort( $sortedBuckets );
 492
 493                 foreach ( $sortedBuckets as $bucket ) {
 494                         if ( $bucket >= $imageWidth ) {
 495                                 return false;
 496                         }
 497
 498                         if ( $bucket - $wgThumbnailMinimumBucketDistance > $desiredWidth ) {
 499                                 return $bucket;
 500                         }
 501                 }
 502
 503                 // Image is bigger than any available bucket
 504                 return false;
 505         }
 506
 507         /**
 508          * Returns ID or name of user who uploaded the file
 509          * STUB
 510          *
 511          * @param string $type 'text' or 'id'
 512          * @return string|int
 513          */
 514         public function getUser( $type = 'text' ) {
 515                 return null;
 516         }
 517
 518         /**
 519          * Get the duration of a media file in seconds
 520          *
 521          * @return int
 522          */
 523         public function getLength() {
 524                 $handler = $this->getHandler();
 525                 if ( $handler ) {
 526                         return $handler->getLength( $this );
 527                 } else {
 528                         return 0;
 529                 }
 530         }
 531
 532         /**
 533          * Return true if the file is vectorized
 534          *
 535          * @return bool
 536          */
 537         public function isVectorized() {
 538                 $handler = $this->getHandler();
 539                 if ( $handler ) {
 540                         return $handler->isVectorized( $this );
 541                 } else {
 542                         return false;
 543                 }
 544         }
 545
 546         /**
 547          * Gives a (possibly empty) list of languages to render
 548          * the file in.
 549          *
 550          * If the file doesn't have translations, or if the file
 551          * format does not support that sort of thing, returns
 552          * an empty array.
 553          *
 554          * @return array
 555          * @since 1.23
 556          */
 557         public function getAvailableLanguages() {
 558                 $handler = $this->getHandler();
 559                 if ( $handler ) {
 560                         return $handler->getAvailableLanguages( $this );
 561                 } else {
 562                         return array();
 563                 }
 564         }
 565
 566         /**
 567          * In files that support multiple language, what is the default language
 568          * to use if none specified.
 569          *
 570          * @return string Lang code, or null if filetype doesn't support multiple languages.
 571          * @since 1.23
 572          */
 573         public function getDefaultRenderLanguage() {
 574                 $handler = $this->getHandler();
 575                 if ( $handler ) {
 576                         return $handler->getDefaultRenderLanguage( $this );
 577                 } else {
 578                         return null;
 579                 }
 580         }
 581
 582         /**
 583          * Will the thumbnail be animated if one would expect it to be.
 584          *
 585          * Currently used to add a warning to the image description page
 586          *
 587          * @return bool False if the main image is both animated
 588          *   and the thumbnail is not. In all other cases must return
 589          *   true. If image is not renderable whatsoever, should
 590          *   return true.
 591          */
 592         public function canAnimateThumbIfAppropriate() {
 593                 $handler = $this->getHandler();
 594                 if ( !$handler ) {
 595                         // We cannot handle image whatsoever, thus
 596                         // one would not expect it to be animated
 597                         // so true.
 598                         return true;
 599                 } else {
 600                         if ( $this->allowInlineDisplay()
 601                                 && $handler->isAnimatedImage( $this )
 602                                 && !$handler->canAnimateThumbnail( $this )
 603                         ) {
 604                                 // Image is animated, but thumbnail isn't.
 605                                 // This is unexpected to the user.
 606                                 return false;
 607                         } else {
 608                                 // Image is not animated, so one would
 609                                 // not expect thumb to be
 610                                 return true;
 611                         }
 612                 }
 613         }
 614
 615         /**
 616          * Get handler-specific metadata
 617          * Overridden by LocalFile, UnregisteredLocalFile
 618          * STUB
 619          * @return bool|array
 620          */
 621         public function getMetadata() {
 622                 return false;
 623         }
 624
 625         /**
 626          * Like getMetadata but returns a handler independent array of common values.
 627          * @see MediaHandler::getCommonMetaArray()
 628          * @return array|bool Array or false if not supported
 629          * @since 1.23
 630          */
 631         public function getCommonMetaArray() {
 632                 $handler = $this->getHandler();
 633
 634                 if ( !$handler ) {
 635                         return false;
 636                 }
 637
 638                 return $handler->getCommonMetaArray( $this );
 639         }
 640
 641         /**
 642          * get versioned metadata
 643          *
 644          * @param array|string $metadata Array or string of (serialized) metadata
 645          * @param int $version Version number.
 646          * @return array Array containing metadata, or what was passed to it on fail
 647          *   (unserializing if not array)
 648          */
 649         public function convertMetadataVersion( $metadata, $version ) {
 650                 $handler = $this->getHandler();
 651                 if ( !is_array( $metadata ) ) {
 652                         // Just to make the return type consistent
 653                         $metadata = unserialize( $metadata );
 654                 }
 655                 if ( $handler ) {
 656                         return $handler->convertMetadataVersion( $metadata, $version );
 657                 } else {
 658                         return $metadata;
 659                 }
 660         }
 661
 662         /**
 663          * Return the bit depth of the file
 664          * Overridden by LocalFile
 665          * STUB
 666          * @return int
 667          */
 668         public function getBitDepth() {
 669                 return 0;
 670         }
 671
 672         /**
 673          * Return the size of the image file, in bytes
 674          * Overridden by LocalFile, UnregisteredLocalFile
 675          * STUB
 676          * @return bool
 677          */
 678         public function getSize() {
 679                 return false;
 680         }
 681
 682         /**
 683          * Returns the MIME type of the file.
 684          * Overridden by LocalFile, UnregisteredLocalFile
 685          * STUB
 686          *
 687          * @return string
 688          */
 689         function getMimeType() {
 690                 return 'unknown/unknown';
 691         }
 692
 693         /**
 694          * Return the type of the media in the file.
 695          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 696          * Overridden by LocalFile,
 697          * STUB
 698          * @return string
 699          */
 700         function getMediaType() {
 701                 return MEDIATYPE_UNKNOWN;
 702         }
 703
 704         /**
 705          * Checks if the output of transform() for this file is likely
 706          * to be valid. If this is false, various user elements will
 707          * display a placeholder instead.
 708          *
 709          * Currently, this checks if the file is an image format
 710          * that can be converted to a format
 711          * supported by all browsers (namely GIF, PNG and JPEG),
 712          * or if it is an SVG image and SVG conversion is enabled.
 713          *
 714          * @return bool
 715          */
 716         function canRender() {
 717                 if ( !isset( $this->canRender ) ) {
 718                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this ) && $this->exists();
 719                 }
 720
 721                 return $this->canRender;
 722         }
 723
 724         /**
 725          * Accessor for __get()
 726          * @return bool
 727          */
 728         protected function getCanRender() {
 729                 return $this->canRender();
 730         }
 731
 732         /**
 733          * Return true if the file is of a type that can't be directly
 734          * rendered by typical browsers and needs to be re-rasterized.
 735          *
 736          * This returns true for everything but the bitmap types
 737          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 738          * also return true for any non-image formats.
 739          *
 740          * @return bool
 741          */
 742         function mustRender() {
 743                 return $this->getHandler() && $this->handler->mustRender( $this );
 744         }
 745
 746         /**
 747          * Alias for canRender()
 748          *
 749          * @return bool
 750          */
 751         function allowInlineDisplay() {
 752                 return $this->canRender();
 753         }
 754
 755         /**
 756          * Determines if this media file is in a format that is unlikely to
 757          * contain viruses or malicious content. It uses the global
 758          * $wgTrustedMediaFormats list to determine if the file is safe.
 759          *
 760          * This is used to show a warning on the description page of non-safe files.
 761          * It may also be used to disallow direct [[media:...]] links to such files.
 762          *
 763          * Note that this function will always return true if allowInlineDisplay()
 764          * or isTrustedFile() is true for this file.
 765          *
 766          * @return bool
 767          */
 768         function isSafeFile() {
 769                 if ( !isset( $this->isSafeFile ) ) {
 770                         $this->isSafeFile = $this->getIsSafeFileUncached();
 771                 }
 772
 773                 return $this->isSafeFile;
 774         }
 775
 776         /**
 777          * Accessor for __get()
 778          *
 779          * @return bool
 780          */
 781         protected function getIsSafeFile() {
 782                 return $this->isSafeFile();
 783         }
 784
 785         /**
 786          * Uncached accessor
 787          *
 788          * @return bool
 789          */
 790         protected function getIsSafeFileUncached() {
 791                 global $wgTrustedMediaFormats;
 792
 793                 if ( $this->allowInlineDisplay() ) {
 794                         return true;
 795                 }
 796                 if ( $this->isTrustedFile() ) {
 797                         return true;
 798                 }
 799
 800                 $type = $this->getMediaType();
 801                 $mime = $this->getMimeType();
 802                 #wfDebug( "LocalFile::isSafeFile: type= $type, mime= $mime\n" );
 803
 804                 if ( !$type || $type === MEDIATYPE_UNKNOWN ) {
 805                         return false; #unknown type, not trusted
 806                 }
 807                 if ( in_array( $type, $wgTrustedMediaFormats ) ) {
 808                         return true;
 809                 }
 810
 811                 if ( $mime === "unknown/unknown" ) {
 812                         return false; #unknown type, not trusted
 813                 }
 814                 if ( in_array( $mime, $wgTrustedMediaFormats ) ) {
 815                         return true;
 816                 }
 817
 818                 return false;
 819         }
 820
 821         /**
 822          * Returns true if the file is flagged as trusted. Files flagged that way
 823          * can be linked to directly, even if that is not allowed for this type of
 824          * file normally.
 825          *
 826          * This is a dummy function right now and always returns false. It could be
 827          * implemented to extract a flag from the database. The trusted flag could be
 828          * set on upload, if the user has sufficient privileges, to bypass script-
 829          * and html-filters. It may even be coupled with cryptographics signatures
 830          * or such.
 831          *
 832          * @return bool
 833          */
 834         function isTrustedFile() {
 835                 #this could be implemented to check a flag in the database,
 836                 #look for signatures, etc
 837                 return false;
 838         }
 839
 840         /**
 841          * Load any lazy-loaded file object fields from source
 842          *
 843          * This is only useful when setting $flags
 844          *
 845          * Overridden by LocalFile to actually query the DB
 846          *
 847          * @param integer $flags Bitfield of File::READ_* constants
 848          */
 849         public function load( $flags = 0 ) {
 850         }
 851
 852         /**
 853          * Returns true if file exists in the repository.
 854          *
 855          * Overridden by LocalFile to avoid unnecessary stat calls.
 856          *
 857          * @return bool Whether file exists in the repository.
 858          */
 859         public function exists() {
 860                 return $this->getPath() && $this->repo->fileExists( $this->path );
 861         }
 862
 863         /**
 864          * Returns true if file exists in the repository and can be included in a page.
 865          * It would be unsafe to include private images, making public thumbnails inadvertently
 866          *
 867          * @return bool Whether file exists in the repository and is includable.
 868          */
 869         public function isVisible() {
 870                 return $this->exists();
 871         }
 872
 873         /**
 874          * @return string
 875          */
 876         function getTransformScript() {
 877                 if ( !isset( $this->transformScript ) ) {
 878                         $this->transformScript = false;
 879                         if ( $this->repo ) {
 880                                 $script = $this->repo->getThumbScriptUrl();
 881                                 if ( $script ) {
 882                                         $this->transformScript = wfAppendQuery( $script, array( 'f' => $this->getName() ) );
 883                                 }
 884                         }
 885                 }
 886
 887                 return $this->transformScript;
 888         }
 889
 890         /**
 891          * Get a ThumbnailImage which is the same size as the source
 892          *
 893          * @param array $handlerParams
 894          *
 895          * @return string
 896          */
 897         function getUnscaledThumb( $handlerParams = array() ) {
 898                 $hp =& $handlerParams;
 899                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 900                 $width = $this->getWidth( $page );
 901                 if ( !$width ) {
 902                         return $this->iconThumb();
 903                 }
 904                 $hp['width'] = $width;
 905                 // be sure to ignore any height specification as well (bug 62258)
 906                 unset( $hp['height'] );
 907
 908                 return $this->transform( $hp );
 909         }
 910
 911         /**
 912          * Return the file name of a thumbnail with the specified parameters.
 913          * Use File::THUMB_FULL_NAME to always get a name like "<params>-<source>".
 914          * Otherwise, the format may be "<params>-<source>" or "<params>-thumbnail.<ext>".
 915          *
 916          * @param array $params Handler-specific parameters
 917          * @param int $flags Bitfield that supports THUMB_* constants
 918          * @return string
 919          */
 920         public function thumbName( $params, $flags = 0 ) {
 921                 $name = ( $this->repo && !( $flags & self::THUMB_FULL_NAME ) )
 922                         ? $this->repo->nameForThumb( $this->getName() )
 923                         : $this->getName();
 924
 925                 return $this->generateThumbName( $name, $params );
 926         }
 927
 928         /**
 929          * Generate a thumbnail file name from a name and specified parameters
 930          *
 931          * @param string $name
 932          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 933          * @return string
 934          */
 935         public function generateThumbName( $name, $params ) {
 936                 if ( !$this->getHandler() ) {
 937                         return null;
 938                 }
 939                 $extension = $this->getExtension();
 940                 list( $thumbExt, ) = $this->getHandler()->getThumbType(
 941                         $extension, $this->getMimeType(), $params );
 942                 $thumbName = $this->getHandler()->makeParamString( $params ) . '-' . $name;
 943                 if ( $thumbExt != $extension ) {
 944                         $thumbName .= ".$thumbExt";
 945                 }
 946
 947                 return $thumbName;
 948         }
 949
 950         /**
 951          * Create a thumbnail of the image having the specified width/height.
 952          * The thumbnail will not be created if the width is larger than the
 953          * image's width. Let the browser do the scaling in this case.
 954          * The thumbnail is stored on disk and is only computed if the thumbnail
 955          * file does not exist OR if it is older than the image.
 956          * Returns the URL.
 957          *
 958          * Keeps aspect ratio of original image. If both width and height are
 959          * specified, the generated image will be no bigger than width x height,
 960          * and will also have correct aspect ratio.
 961          *
 962          * @param int $width Maximum width of the generated thumbnail
 963          * @param int $height Maximum height of the image (optional)
 964          *
 965          * @return string
 966          */
 967         public function createThumb( $width, $height = -1 ) {
 968                 $params = array( 'width' => $width );
 969                 if ( $height != -1 ) {
 970                         $params['height'] = $height;
 971                 }
 972                 $thumb = $this->transform( $params );
 973                 if ( !$thumb || $thumb->isError() ) {
 974                         return '';
 975                 }
 976
 977                 return $thumb->getUrl();
 978         }
 979
 980         /**
 981          * Return either a MediaTransformError or placeholder thumbnail (if $wgIgnoreImageErrors)
 982          *
 983          * @param string $thumbPath Thumbnail storage path
 984          * @param string $thumbUrl Thumbnail URL
 985          * @param array $params
 986          * @param int $flags
 987          * @return MediaTransformOutput
 988          */
 989         protected function transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags ) {
 990                 global $wgIgnoreImageErrors;
 991
 992                 $handler = $this->getHandler();
 993                 if ( $handler && $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
 994                         return $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 995                 } else {
 996                         return new MediaTransformError( 'thumbnail_error',
 997                                 $params['width'], 0, wfMessage( 'thumbnail-dest-create' )->text() );
 998                 }
 999         }
1000
1001         /**
1002          * Transform a media file
1003          *
1004          * @param array $params An associative array of handler-specific parameters.
1005          *   Typical keys are width, height and page.
1006          * @param int $flags A bitfield, may contain self::RENDER_NOW to force rendering
1007          * @return MediaTransformOutput|bool False on failure
1008          */
1009         function transform( $params, $flags = 0 ) {
1010                 global $wgThumbnailEpoch;
1011
1012                 do {
1013                         if ( !$this->canRender() ) {
1014                                 $thumb = $this->iconThumb();
1015                                 break; // not a bitmap or renderable image, don't try
1016                         }
1017
1018                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
1019                         $descriptionUrl = $this->getDescriptionUrl();
1020                         if ( $descriptionUrl ) {
1021                                 $params['descriptionUrl'] = wfExpandUrl( $descriptionUrl, PROTO_CANONICAL );
1022                         }
1023
1024                         $handler = $this->getHandler();
1025                         $script = $this->getTransformScript();
1026                         if ( $script && !( $flags & self::RENDER_NOW ) ) {
1027                                 // Use a script to transform on client request, if possible
1028                                 $thumb = $handler->getScriptedTransform( $this, $script, $params );
1029                                 if ( $thumb ) {
1030                                         break;
1031                                 }
1032                         }
1033
1034                         $normalisedParams = $params;
1035                         $handler->normaliseParams( $this, $normalisedParams );
1036
1037                         $thumbName = $this->thumbName( $normalisedParams );
1038                         $thumbUrl = $this->getThumbUrl( $thumbName );
1039                         $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1040
1041                         if ( $this->repo ) {
1042                                 // Defer rendering if a 404 handler is set up...
1043                                 if ( $this->repo->canTransformVia404() && !( $flags & self::RENDER_NOW ) ) {
1044                                         wfDebug( __METHOD__ . " transformation deferred.\n" );
1045                                         // XXX: Pass in the storage path even though we are not rendering anything
1046                                         // and the path is supposed to be an FS path. This is due to getScalerType()
1047                                         // getting called on the path and clobbering $thumb->getUrl() if it's false.
1048                                         $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
1049                                         break;
1050                                 }
1051                                 // Check if an up-to-date thumbnail already exists...
1052                                 wfDebug( __METHOD__ . ": Doing stat for $thumbPath\n" );
1053                                 if ( !( $flags & self::RENDER_FORCE ) && $this->repo->fileExists( $thumbPath ) ) {
1054                                         $timestamp = $this->repo->getFileTimestamp( $thumbPath );
1055                                         if ( $timestamp !== false && $timestamp >= $wgThumbnailEpoch ) {
1056                                                 // XXX: Pass in the storage path even though we are not rendering anything
1057                                                 // and the path is supposed to be an FS path. This is due to getScalerType()
1058                                                 // getting called on the path and clobbering $thumb->getUrl() if it's false.
1059                                                 $thumb = $handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
1060                                                 $thumb->setStoragePath( $thumbPath );
1061                                                 break;
1062                                         }
1063                                 } elseif ( $flags & self::RENDER_FORCE ) {
1064                                         wfDebug( __METHOD__ . " forcing rendering per flag File::RENDER_FORCE\n" );
1065                                 }
1066
1067                                 // If the backend is ready-only, don't keep generating thumbnails
1068                                 // only to return transformation errors, just return the error now.
1069                                 if ( $this->repo->getReadOnlyReason() !== false ) {
1070                                         $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1071                                         break;
1072                                 }
1073                         }
1074
1075                         $tmpFile = $this->makeTransformTmpFile( $thumbPath );
1076
1077                         if ( !$tmpFile ) {
1078                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $params, $flags );
1079                         } else {
1080                                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1081                         }
1082                 } while ( false );
1083
1084                 return is_object( $thumb ) ? $thumb : false;
1085         }
1086
1087         /**
1088          * Generates a thumbnail according to the given parameters and saves it to storage
1089          * @param TempFSFile $tmpFile Temporary file where the rendered thumbnail will be saved
1090          * @param array $transformParams
1091          * @param int $flags
1092          * @return bool|MediaTransformOutput
1093          */
1094         public function generateAndSaveThumb( $tmpFile, $transformParams, $flags ) {
1095                 global $wgUseSquid, $wgIgnoreImageErrors;
1096
1097                 $handler = $this->getHandler();
1098
1099                 $normalisedParams = $transformParams;
1100                 $handler->normaliseParams( $this, $normalisedParams );
1101
1102                 $thumbName = $this->thumbName( $normalisedParams );
1103                 $thumbUrl = $this->getThumbUrl( $thumbName );
1104                 $thumbPath = $this->getThumbPath( $thumbName ); // final thumb path
1105
1106                 $tmpThumbPath = $tmpFile->getPath();
1107
1108                 if ( $handler->supportsBucketing() ) {
1109                         $this->generateBucketsIfNeeded( $normalisedParams, $flags );
1110                 }
1111
1112                 // Actually render the thumbnail...
1113                 $thumb = $handler->doTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1114                 $tmpFile->bind( $thumb ); // keep alive with $thumb
1115
1116                 if ( !$thumb ) { // bad params?
1117                         $thumb = false;
1118                 } elseif ( $thumb->isError() ) { // transform error
1119                         $this->lastError = $thumb->toText();
1120                         // Ignore errors if requested
1121                         if ( $wgIgnoreImageErrors && !( $flags & self::RENDER_NOW ) ) {
1122                                 $thumb = $handler->getTransform( $this, $tmpThumbPath, $thumbUrl, $transformParams );
1123                         }
1124                 } elseif ( $this->repo && $thumb->hasFile() && !$thumb->fileIsSource() ) {
1125                         // Copy the thumbnail from the file system into storage...
1126                         $disposition = $this->getThumbDisposition( $thumbName );
1127                         $status = $this->repo->quickImport( $tmpThumbPath, $thumbPath, $disposition );
1128                         if ( $status->isOK() ) {
1129                                 $thumb->setStoragePath( $thumbPath );
1130                         } else {
1131                                 $thumb = $this->transformErrorOutput( $thumbPath, $thumbUrl, $transformParams, $flags );
1132                         }
1133                         // Give extensions a chance to do something with this thumbnail...
1134                         Hooks::run( 'FileTransformed', array( $this, $thumb, $tmpThumbPath, $thumbPath ) );
1135                 }
1136
1137                 // Purge. Useful in the event of Core -> Squid connection failure or squid
1138                 // purge collisions from elsewhere during failure. Don't keep triggering for
1139                 // "thumbs" which have the main image URL though (bug 13776)
1140                 if ( $wgUseSquid ) {
1141                         if ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL() ) {
1142                                 SquidUpdate::purge( array( $thumbUrl ) );
1143                         }
1144                 }
1145
1146                 return $thumb;
1147         }
1148
1149         /**
1150          * Generates chained bucketed thumbnails if needed
1151          * @param array $params
1152          * @param int $flags
1153          * @return bool Whether at least one bucket was generated
1154          */
1155         protected function generateBucketsIfNeeded( $params, $flags = 0 ) {
1156                 if ( !$this->repo
1157                         || !isset( $params['physicalWidth'] )
1158                         || !isset( $params['physicalHeight'] )
1159                         || !( $bucket = $this->getThumbnailBucket( $params['physicalWidth'] ) )
1160                         || $bucket == $params['physicalWidth'] ) {
1161                         return false;
1162                 }
1163
1164                 $bucketPath = $this->getBucketThumbPath( $bucket );
1165
1166                 if ( $this->repo->fileExists( $bucketPath ) ) {
1167                         return false;
1168                 }
1169
1170                 $params['physicalWidth'] = $bucket;
1171                 $params['width'] = $bucket;
1172
1173                 $params = $this->getHandler()->sanitizeParamsForBucketing( $params );
1174
1175                 $bucketName = $this->getBucketThumbName( $bucket );
1176
1177                 $tmpFile = $this->makeTransformTmpFile( $bucketPath );
1178
1179                 if ( !$tmpFile ) {
1180                         return false;
1181                 }
1182
1183                 $thumb = $this->generateAndSaveThumb( $tmpFile, $params, $flags );
1184
1185                 if ( !$thumb || $thumb->isError() ) {
1186                         return false;
1187                 }
1188
1189                 $this->tmpBucketedThumbCache[$bucket] = $tmpFile->getPath();
1190                 // For the caching to work, we need to make the tmp file survive as long as
1191                 // this object exists
1192                 $tmpFile->bind( $this );
1193
1194                 return true;
1195         }
1196
1197         /**
1198          * Returns the most appropriate source image for the thumbnail, given a target thumbnail size
1199          * @param array $params
1200          * @return array Source path and width/height of the source
1201          */
1202         public function getThumbnailSource( $params ) {
1203                 if ( $this->repo
1204                         && $this->getHandler()->supportsBucketing()
1205                         && isset( $params['physicalWidth'] )
1206                         && $bucket = $this->getThumbnailBucket( $params['physicalWidth'] )
1207                 ) {
1208                         if ( $this->getWidth() != 0 ) {
1209                                 $bucketHeight = round( $this->getHeight() * ( $bucket / $this->getWidth() ) );
1210                         } else {
1211                                 $bucketHeight = 0;
1212                         }
1213
1214                         // Try to avoid reading from storage if the file was generated by this script
1215                         if ( isset( $this->tmpBucketedThumbCache[$bucket] ) ) {
1216                                 $tmpPath = $this->tmpBucketedThumbCache[$bucket];
1217
1218                                 if ( file_exists( $tmpPath ) ) {
1219                                         return array(
1220                                                 'path' => $tmpPath,
1221                                                 'width' => $bucket,
1222                                                 'height' => $bucketHeight
1223                                         );
1224                                 }
1225                         }
1226
1227                         $bucketPath = $this->getBucketThumbPath( $bucket );
1228
1229                         if ( $this->repo->fileExists( $bucketPath ) ) {
1230                                 $fsFile = $this->repo->getLocalReference( $bucketPath );
1231
1232                                 if ( $fsFile ) {
1233                                         return array(
1234                                                 'path' => $fsFile->getPath(),
1235                                                 'width' => $bucket,
1236                                                 'height' => $bucketHeight
1237                                         );
1238                                 }
1239                         }
1240                 }
1241
1242                 // Thumbnailing a very large file could result in network saturation if
1243                 // everyone does it at once.
1244                 if ( $this->getSize() >= 1e7 ) { // 10MB
1245                         $that = $this;
1246                         $work = new PoolCounterWorkViaCallback( 'GetLocalFileCopy', sha1( $this->getName() ),
1247                                 array(
1248                                         'doWork' => function () use ( $that ) {
1249                                                 return $that->getLocalRefPath();
1250                                         }
1251                                 )
1252                         );
1253                         $srcPath = $work->execute();
1254                 } else {
1255                         $srcPath = $this->getLocalRefPath();
1256                 }
1257
1258                 // Original file
1259                 return array(
1260                         'path' => $srcPath,
1261                         'width' => $this->getWidth(),
1262                         'height' => $this->getHeight()
1263                 );
1264         }
1265
1266         /**
1267          * Returns the repo path of the thumb for a given bucket
1268          * @param int $bucket
1269          * @return string
1270          */
1271         protected function getBucketThumbPath( $bucket ) {
1272                 $thumbName = $this->getBucketThumbName( $bucket );
1273                 return $this->getThumbPath( $thumbName );
1274         }
1275
1276         /**
1277          * Returns the name of the thumb for a given bucket
1278          * @param int $bucket
1279          * @return string
1280          */
1281         protected function getBucketThumbName( $bucket ) {
1282                 return $this->thumbName( array( 'physicalWidth' => $bucket ) );
1283         }
1284
1285         /**
1286          * Creates a temp FS file with the same extension and the thumbnail
1287          * @param string $thumbPath Thumbnail path
1288          * @return TempFSFile
1289          */
1290         protected function makeTransformTmpFile( $thumbPath ) {
1291                 $thumbExt = FileBackend::extensionFromPath( $thumbPath );
1292                 return TempFSFile::factory( 'transform_', $thumbExt );
1293         }
1294
1295         /**
1296          * @param string $thumbName Thumbnail name
1297          * @param string $dispositionType Type of disposition (either "attachment" or "inline")
1298          * @return string Content-Disposition header value
1299          */
1300         function getThumbDisposition( $thumbName, $dispositionType = 'inline' ) {
1301                 $fileName = $this->name; // file name to suggest
1302                 $thumbExt = FileBackend::extensionFromPath( $thumbName );
1303                 if ( $thumbExt != '' && $thumbExt !== $this->getExtension() ) {
1304                         $fileName .= ".$thumbExt";
1305                 }
1306
1307                 return FileBackend::makeContentDisposition( $dispositionType, $fileName );
1308         }
1309
1310         /**
1311          * Hook into transform() to allow migration of thumbnail files
1312          * STUB
1313          * Overridden by LocalFile
1314          * @param string $thumbName
1315          */
1316         function migrateThumbFile( $thumbName ) {
1317         }
1318
1319         /**
1320          * Get a MediaHandler instance for this file
1321          *
1322          * @return MediaHandler|bool Registered MediaHandler for file's MIME type
1323          *   or false if none found
1324          */
1325         function getHandler() {
1326                 if ( !isset( $this->handler ) ) {
1327                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
1328                 }
1329
1330                 return $this->handler;
1331         }
1332
1333         /**
1334          * Get a ThumbnailImage representing a file type icon
1335          *
1336          * @return ThumbnailImage
1337          */
1338         function iconThumb() {
1339                 global $wgResourceBasePath, $IP;
1340                 $assetsPath = "$wgResourceBasePath/resources/assets/file-type-icons/";
1341                 $assetsDirectory = "$IP/resources/assets/file-type-icons/";
1342
1343                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
1344                 foreach ( $try as $icon ) {
1345                         if ( file_exists( $assetsDirectory . $icon ) ) { // always FS
1346                                 $params = array( 'width' => 120, 'height' => 120 );
1347
1348                                 return new ThumbnailImage( $this, $assetsPath . $icon, false, $params );
1349                         }
1350                 }
1351
1352                 return null;
1353         }
1354
1355         /**
1356          * Get last thumbnailing error.
1357          * Largely obsolete.
1358          * @return string
1359          */
1360         function getLastError() {
1361                 return $this->lastError;
1362         }
1363
1364         /**
1365          * Get all thumbnail names previously generated for this file
1366          * STUB
1367          * Overridden by LocalFile
1368          * @return array
1369          */
1370         function getThumbnails() {
1371                 return array();
1372         }
1373
1374         /**
1375          * Purge shared caches such as thumbnails and DB data caching
1376          * STUB
1377          * Overridden by LocalFile
1378          * @param array $options Options, which include:
1379          *   'forThumbRefresh' : The purging is only to refresh thumbnails
1380          */
1381         function purgeCache( $options = array() ) {
1382         }
1383
1384         /**
1385          * Purge the file description page, but don't go after
1386          * pages using the file. Use when modifying file history
1387          * but not the current data.
1388          */
1389         function purgeDescription() {
1390                 $title = $this->getTitle();
1391                 if ( $title ) {
1392                         $title->invalidateCache();
1393                         $title->purgeSquid();
1394                 }
1395         }
1396
1397         /**
1398          * Purge metadata and all affected pages when the file is created,
1399          * deleted, or majorly updated.
1400          */
1401         function purgeEverything() {
1402                 // Delete thumbnails and refresh file metadata cache
1403                 $this->purgeCache();
1404                 $this->purgeDescription();
1405
1406                 // Purge cache of all pages using this file
1407                 $title = $this->getTitle();
1408                 if ( $title ) {
1409                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
1410                         $update->doUpdate();
1411                 }
1412         }
1413
1414         /**
1415          * Return a fragment of the history of file.
1416          *
1417          * STUB
1418          * @param int $limit Limit of rows to return
1419          * @param string $start Only revisions older than $start will be returned
1420          * @param string $end Only revisions newer than $end will be returned
1421          * @param bool $inc Include the endpoints of the time range
1422          *
1423          * @return array
1424          */
1425         function getHistory( $limit = null, $start = null, $end = null, $inc = true ) {
1426                 return array();
1427         }
1428
1429         /**
1430          * Return the history of this file, line by line. Starts with current version,
1431          * then old versions. Should return an object similar to an image/oldimage
1432          * database row.
1433          *
1434          * STUB
1435          * Overridden in LocalFile
1436          * @return bool
1437          */
1438         public function nextHistoryLine() {
1439                 return false;
1440         }
1441
1442         /**
1443          * Reset the history pointer to the first element of the history.
1444          * Always call this function after using nextHistoryLine() to free db resources
1445          * STUB
1446          * Overridden in LocalFile.
1447          */
1448         public function resetHistory() {
1449         }
1450
1451         /**
1452          * Get the filename hash component of the directory including trailing slash,
1453          * e.g. f/fa/
1454          * If the repository is not hashed, returns an empty string.
1455          *
1456          * @return string
1457          */
1458         function getHashPath() {
1459                 if ( !isset( $this->hashPath ) ) {
1460                         $this->assertRepoDefined();
1461                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
1462                 }
1463
1464                 return $this->hashPath;
1465         }
1466
1467         /**
1468          * Get the path of the file relative to the public zone root.
1469          * This function is overridden in OldLocalFile to be like getArchiveRel().
1470          *
1471          * @return string
1472          */
1473         function getRel() {
1474                 return $this->getHashPath() . $this->getName();
1475         }
1476
1477         /**
1478          * Get the path of an archived file relative to the public zone root
1479          *
1480          * @param bool|string $suffix If not false, the name of an archived thumbnail file
1481          *
1482          * @return string
1483          */
1484         function getArchiveRel( $suffix = false ) {
1485                 $path = 'archive/' . $this->getHashPath();
1486                 if ( $suffix === false ) {
1487                         $path = substr( $path, 0, -1 );
1488                 } else {
1489                         $path .= $suffix;
1490                 }
1491
1492                 return $path;
1493         }
1494
1495         /**
1496          * Get the path, relative to the thumbnail zone root, of the
1497          * thumbnail directory or a particular file if $suffix is specified
1498          *
1499          * @param bool|string $suffix If not false, the name of a thumbnail file
1500          * @return string
1501          */
1502         function getThumbRel( $suffix = false ) {
1503                 $path = $this->getRel();
1504                 if ( $suffix !== false ) {
1505                         $path .= '/' . $suffix;
1506                 }
1507
1508                 return $path;
1509         }
1510
1511         /**
1512          * Get urlencoded path of the file relative to the public zone root.
1513          * This function is overridden in OldLocalFile to be like getArchiveUrl().
1514          *
1515          * @return string
1516          */
1517         function getUrlRel() {
1518                 return $this->getHashPath() . rawurlencode( $this->getName() );
1519         }
1520
1521         /**
1522          * Get the path, relative to the thumbnail zone root, for an archived file's thumbs directory
1523          * or a specific thumb if the $suffix is given.
1524          *
1525          * @param string $archiveName The timestamped name of an archived image
1526          * @param bool|string $suffix If not false, the name of a thumbnail file
1527          * @return string
1528          */
1529         function getArchiveThumbRel( $archiveName, $suffix = false ) {
1530                 $path = 'archive/' . $this->getHashPath() . $archiveName . "/";
1531                 if ( $suffix === false ) {
1532                         $path = substr( $path, 0, -1 );
1533                 } else {
1534                         $path .= $suffix;
1535                 }
1536
1537                 return $path;
1538         }
1539
1540         /**
1541          * Get the path of the archived file.
1542          *
1543          * @param bool|string $suffix If not false, the name of an archived file.
1544          * @return string
1545          */
1546         function getArchivePath( $suffix = false ) {
1547                 $this->assertRepoDefined();
1548
1549                 return $this->repo->getZonePath( 'public' ) . '/' . $this->getArchiveRel( $suffix );
1550         }
1551
1552         /**
1553          * Get the path of an archived file's thumbs, or a particular thumb if $suffix is specified
1554          *
1555          * @param string $archiveName The timestamped name of an archived image
1556          * @param bool|string $suffix If not false, the name of a thumbnail file
1557          * @return string
1558          */
1559         function getArchiveThumbPath( $archiveName, $suffix = false ) {
1560                 $this->assertRepoDefined();
1561
1562                 return $this->repo->getZonePath( 'thumb' ) . '/' .
1563                 $this->getArchiveThumbRel( $archiveName, $suffix );
1564         }
1565
1566         /**
1567          * Get the path of the thumbnail directory, or a particular file if $suffix is specified
1568          *
1569          * @param bool|string $suffix If not false, the name of a thumbnail file
1570          * @return string
1571          */
1572         function getThumbPath( $suffix = false ) {
1573                 $this->assertRepoDefined();
1574
1575                 return $this->repo->getZonePath( 'thumb' ) . '/' . $this->getThumbRel( $suffix );
1576         }
1577
1578         /**
1579          * Get the path of the transcoded directory, or a particular file if $suffix is specified
1580          *
1581          * @param bool|string $suffix If not false, the name of a media file
1582          * @return string
1583          */
1584         function getTranscodedPath( $suffix = false ) {
1585                 $this->assertRepoDefined();
1586
1587                 return $this->repo->getZonePath( 'transcoded' ) . '/' . $this->getThumbRel( $suffix );
1588         }
1589
1590         /**
1591          * Get the URL of the archive directory, or a particular file if $suffix is specified
1592          *
1593          * @param bool|string $suffix If not false, the name of an archived file
1594          * @return string
1595          */
1596         function getArchiveUrl( $suffix = false ) {
1597                 $this->assertRepoDefined();
1598                 $ext = $this->getExtension();
1599                 $path = $this->repo->getZoneUrl( 'public', $ext ) . '/archive/' . $this->getHashPath();
1600                 if ( $suffix === false ) {
1601                         $path = substr( $path, 0, -1 );
1602                 } else {
1603                         $path .= rawurlencode( $suffix );
1604                 }
1605
1606                 return $path;
1607         }
1608
1609         /**
1610          * Get the URL of the archived file's thumbs, or a particular thumb if $suffix is specified
1611          *
1612          * @param string $archiveName The timestamped name of an archived image
1613          * @param bool|string $suffix If not false, the name of a thumbnail file
1614          * @return string
1615          */
1616         function getArchiveThumbUrl( $archiveName, $suffix = false ) {
1617                 $this->assertRepoDefined();
1618                 $ext = $this->getExtension();
1619                 $path = $this->repo->getZoneUrl( 'thumb', $ext ) . '/archive/' .
1620                         $this->getHashPath() . rawurlencode( $archiveName ) . "/";
1621                 if ( $suffix === false ) {
1622                         $path = substr( $path, 0, -1 );
1623                 } else {
1624                         $path .= rawurlencode( $suffix );
1625                 }
1626
1627                 return $path;
1628         }
1629
1630         /**
1631          * Get the URL of the zone directory, or a particular file if $suffix is specified
1632          *
1633          * @param string $zone Name of requested zone
1634          * @param bool|string $suffix If not false, the name of a file in zone
1635          * @return string Path
1636          */
1637         function getZoneUrl( $zone, $suffix = false ) {
1638                 $this->assertRepoDefined();
1639                 $ext = $this->getExtension();
1640                 $path = $this->repo->getZoneUrl( $zone, $ext ) . '/' . $this->getUrlRel();
1641                 if ( $suffix !== false ) {
1642                         $path .= '/' . rawurlencode( $suffix );
1643                 }
1644
1645                 return $path;
1646         }
1647
1648         /**
1649          * Get the URL of the thumbnail directory, or a particular file if $suffix is specified
1650          *
1651          * @param bool|string $suffix If not false, the name of a thumbnail file
1652          * @return string Path
1653          */
1654         function getThumbUrl( $suffix = false ) {
1655                 return $this->getZoneUrl( 'thumb', $suffix );
1656         }
1657
1658         /**
1659          * Get the URL of the transcoded directory, or a particular file if $suffix is specified
1660          *
1661          * @param bool|string $suffix If not false, the name of a media file
1662          * @return string Path
1663          */
1664         function getTranscodedUrl( $suffix = false ) {
1665                 return $this->getZoneUrl( 'transcoded', $suffix );
1666         }
1667
1668         /**
1669          * Get the public zone virtual URL for a current version source file
1670          *
1671          * @param bool|string $suffix If not false, the name of a thumbnail file
1672          * @return string
1673          */
1674         function getVirtualUrl( $suffix = false ) {
1675                 $this->assertRepoDefined();
1676                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
1677                 if ( $suffix !== false ) {
1678                         $path .= '/' . rawurlencode( $suffix );
1679                 }
1680
1681                 return $path;
1682         }
1683
1684         /**
1685          * Get the public zone virtual URL for an archived version source file
1686          *
1687          * @param bool|string $suffix If not false, the name of a thumbnail file
1688          * @return string
1689          */
1690         function getArchiveVirtualUrl( $suffix = false ) {
1691                 $this->assertRepoDefined();
1692                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
1693                 if ( $suffix === false ) {
1694                         $path = substr( $path, 0, -1 );
1695                 } else {
1696                         $path .= rawurlencode( $suffix );
1697                 }
1698
1699                 return $path;
1700         }
1701
1702         /**
1703          * Get the virtual URL for a thumbnail file or directory
1704          *
1705          * @param bool|string $suffix If not false, the name of a thumbnail file
1706          * @return string
1707          */
1708         function getThumbVirtualUrl( $suffix = false ) {
1709                 $this->assertRepoDefined();
1710                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
1711                 if ( $suffix !== false ) {
1712                         $path .= '/' . rawurlencode( $suffix );
1713                 }
1714
1715                 return $path;
1716         }
1717
1718         /**
1719          * @return bool
1720          */
1721         function isHashed() {
1722                 $this->assertRepoDefined();
1723
1724                 return (bool)$this->repo->getHashLevels();
1725         }
1726
1727         /**
1728          * @throws MWException
1729          */
1730         function readOnlyError() {
1731                 throw new MWException( get_class( $this ) . ': write operations are not supported' );
1732         }
1733
1734         /**
1735          * Record a file upload in the upload log and the image table
1736          * STUB
1737          * Overridden by LocalFile
1738          * @param string $oldver
1739          * @param string $desc
1740          * @param string $license
1741          * @param string $copyStatus
1742          * @param string $source
1743          * @param bool $watch
1744          * @param string|bool $timestamp
1745          * @param null|User $user User object or null to use $wgUser
1746          * @return bool
1747          * @throws MWException
1748          */
1749         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '',
1750                 $watch = false, $timestamp = false, User $user = null
1751         ) {
1752                 $this->readOnlyError();
1753         }
1754
1755         /**
1756          * Move or copy a file to its public location. If a file exists at the
1757          * destination, move it to an archive. Returns a FileRepoStatus object with
1758          * the archive name in the "value" member on success.
1759          *
1760          * The archive name should be passed through to recordUpload for database
1761          * registration.
1762          *
1763          * Options to $options include:
1764          *   - headers : name/value map of HTTP headers to use in response to GET/HEAD requests
1765          *
1766          * @param string $srcPath Local filesystem path to the source image
1767          * @param int $flags A bitwise combination of:
1768          *   File::DELETE_SOURCE    Delete the source file, i.e. move rather than copy
1769          * @param array $options Optional additional parameters
1770          * @return FileRepoStatus On success, the value member contains the
1771          *   archive name, or an empty string if it was a new file.
1772          *
1773          * STUB
1774          * Overridden by LocalFile
1775          */
1776         function publish( $srcPath, $flags = 0, array $options = array() ) {
1777                 $this->readOnlyError();
1778         }
1779
1780         /**
1781          * @param bool|IContextSource $context Context to use (optional)
1782          * @return bool
1783          */
1784         function formatMetadata( $context = false ) {
1785                 if ( !$this->getHandler() ) {
1786                         return false;
1787                 }
1788
1789                 return $this->getHandler()->formatMetadata( $this, $context );
1790         }
1791
1792         /**
1793          * Returns true if the file comes from the local file repository.
1794          *
1795          * @return bool
1796          */
1797         function isLocal() {
1798                 return $this->repo && $this->repo->isLocal();
1799         }
1800
1801         /**
1802          * Returns the name of the repository.
1803          *
1804          * @return string
1805          */
1806         function getRepoName() {
1807                 return $this->repo ? $this->repo->getName() : 'unknown';
1808         }
1809
1810         /**
1811          * Returns the repository
1812          *
1813          * @return FileRepo|LocalRepo|bool
1814          */
1815         function getRepo() {
1816                 return $this->repo;
1817         }
1818
1819         /**
1820          * Returns true if the image is an old version
1821          * STUB
1822          *
1823          * @return bool
1824          */
1825         function isOld() {
1826                 return false;
1827         }
1828
1829         /**
1830          * Is this file a "deleted" file in a private archive?
1831          * STUB
1832          *
1833          * @param int $field One of DELETED_* bitfield constants
1834          * @return bool
1835          */
1836         function isDeleted( $field ) {
1837                 return false;
1838         }
1839
1840         /**
1841          * Return the deletion bitfield
1842          * STUB
1843          * @return int
1844          */
1845         function getVisibility() {
1846                 return 0;
1847         }
1848
1849         /**
1850          * Was this file ever deleted from the wiki?
1851          *
1852          * @return bool
1853          */
1854         function wasDeleted() {
1855                 $title = $this->getTitle();
1856
1857                 return $title && $title->isDeletedQuick();
1858         }
1859
1860         /**
1861          * Move file to the new title
1862          *
1863          * Move current, old version and all thumbnails
1864          * to the new filename. Old file is deleted.
1865          *
1866          * Cache purging is done; checks for validity
1867          * and logging are caller's responsibility
1868          *
1869          * @param Title $target New file name
1870          * @return FileRepoStatus
1871          */
1872         function move( $target ) {
1873                 $this->readOnlyError();
1874         }
1875
1876         /**
1877          * Delete all versions of the file.
1878          *
1879          * Moves the files into an archive directory (or deletes them)
1880          * and removes the database rows.
1881          *
1882          * Cache purging is done; logging is caller's responsibility.
1883          *
1884          * @param string $reason
1885          * @param bool $suppress Hide content from sysops?
1886          * @param User|null $user
1887          * @return bool Boolean on success, false on some kind of failure
1888          * STUB
1889          * Overridden by LocalFile
1890          */
1891         function delete( $reason, $suppress = false, $user = null ) {
1892                 $this->readOnlyError();
1893         }
1894
1895         /**
1896          * Restore all or specified deleted revisions to the given file.
1897          * Permissions and logging are left to the caller.
1898          *
1899          * May throw database exceptions on error.
1900          *
1901          * @param array $versions Set of record ids of deleted items to restore,
1902          *   or empty to restore all revisions.
1903          * @param bool $unsuppress Remove restrictions on content upon restoration?
1904          * @return int|bool The number of file revisions restored if successful,
1905          *   or false on failure
1906          * STUB
1907          * Overridden by LocalFile
1908          */
1909         function restore( $versions = array(), $unsuppress = false ) {
1910                 $this->readOnlyError();
1911         }
1912
1913         /**
1914          * Returns 'true' if this file is a type which supports multiple pages,
1915          * e.g. DJVU or PDF. Note that this may be true even if the file in
1916          * question only has a single page.
1917          *
1918          * @return bool
1919          */
1920         function isMultipage() {
1921                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1922         }
1923
1924         /**
1925          * Returns the number of pages of a multipage document, or false for
1926          * documents which aren't multipage documents
1927          *
1928          * @return bool|int
1929          */
1930         function pageCount() {
1931                 if ( !isset( $this->pageCount ) ) {
1932                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1933                                 $this->pageCount = $this->handler->pageCount( $this );
1934                         } else {
1935                                 $this->pageCount = false;
1936                         }
1937                 }
1938
1939                 return $this->pageCount;
1940         }
1941
1942         /**
1943          * Calculate the height of a thumbnail using the source and destination width
1944          *
1945          * @param int $srcWidth
1946          * @param int $srcHeight
1947          * @param int $dstWidth
1948          *
1949          * @return int
1950          */
1951         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1952                 // Exact integer multiply followed by division
1953                 if ( $srcWidth == 0 ) {
1954                         return 0;
1955                 } else {
1956                         return round( $srcHeight * $dstWidth / $srcWidth );
1957                 }
1958         }
1959
1960         /**
1961          * Get an image size array like that returned by getImageSize(), or false if it
1962          * can't be determined. Loads the image size directly from the file ignoring caches.
1963          *
1964          * @note Use getWidth()/getHeight() instead of this method unless you have a
1965          *  a good reason. This method skips all caches.
1966          *
1967          * @param string $filePath The path to the file (e.g. From getLocalPathRef() )
1968          * @return array The width, followed by height, with optionally more things after
1969          */
1970         function getImageSize( $filePath ) {
1971                 if ( !$this->getHandler() ) {
1972                         return false;
1973                 }
1974
1975                 return $this->getHandler()->getImageSize( $this, $filePath );
1976         }
1977
1978         /**
1979          * Get the URL of the image description page. May return false if it is
1980          * unknown or not applicable.
1981          *
1982          * @return string
1983          */
1984         function getDescriptionUrl() {
1985                 if ( $this->repo ) {
1986                         return $this->repo->getDescriptionUrl( $this->getName() );
1987                 } else {
1988                         return false;
1989                 }
1990         }
1991
1992         /**
1993          * Get the HTML text of the description page, if available
1994          *
1995          * @param bool|Language $lang Optional language to fetch description in
1996          * @return string
1997          */
1998         function getDescriptionText( $lang = false ) {
1999                 global $wgMemc, $wgLang;
2000                 if ( !$this->repo || !$this->repo->fetchDescription ) {
2001                         return false;
2002                 }
2003                 if ( !$lang ) {
2004                         $lang = $wgLang;
2005                 }
2006                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $lang->getCode() );
2007                 if ( $renderUrl ) {
2008                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
2009                                 wfDebug( "Attempting to get the description from cache..." );
2010                                 $key = $this->repo->getLocalCacheKey(
2011                                         'RemoteFileDescription',
2012                                         'url',
2013                                         $lang->getCode(),
2014                                         $this->getName()
2015                                 );
2016                                 $obj = $wgMemc->get( $key );
2017                                 if ( $obj ) {
2018                                         wfDebug( "success!\n" );
2019
2020                                         return $obj;
2021                                 }
2022                                 wfDebug( "miss\n" );
2023                         }
2024                         wfDebug( "Fetching shared description from $renderUrl\n" );
2025                         $res = Http::get( $renderUrl, array(), __METHOD__ );
2026                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
2027                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
2028                         }
2029
2030                         return $res;
2031                 } else {
2032                         return false;
2033                 }
2034         }
2035
2036         /**
2037          * Get description of file revision
2038          * STUB
2039          *
2040          * @param int $audience One of:
2041          *   File::FOR_PUBLIC       to be displayed to all users
2042          *   File::FOR_THIS_USER    to be displayed to the given user
2043          *   File::RAW              get the description regardless of permissions
2044          * @param User $user User object to check for, only if FOR_THIS_USER is
2045          *   passed to the $audience parameter
2046          * @return string
2047          */
2048         function getDescription( $audience = self::FOR_PUBLIC, User $user = null ) {
2049                 return null;
2050         }
2051
2052         /**
2053          * Get the 14-character timestamp of the file upload
2054          *
2055          * @return string|bool TS_MW timestamp or false on failure
2056          */
2057         function getTimestamp() {
2058                 $this->assertRepoDefined();
2059
2060                 return $this->repo->getFileTimestamp( $this->getPath() );
2061         }
2062
2063         /**
2064          * Returns the timestamp (in TS_MW format) of the last change of the description page.
2065          * Returns false if the file does not have a description page, or retrieving the timestamp
2066          * would be expensive.
2067          * @since 1.25
2068          * @return string|bool
2069          */
2070         public function getDescriptionTouched() {
2071                 return false;
2072         }
2073
2074         /**
2075          * Get the SHA-1 base 36 hash of the file
2076          *
2077          * @return string
2078          */
2079         function getSha1() {
2080                 $this->assertRepoDefined();
2081
2082                 return $this->repo->getFileSha1( $this->getPath() );
2083         }
2084
2085         /**
2086          * Get the deletion archive key, "<sha1>.<ext>"
2087          *
2088          * @return string
2089          */
2090         function getStorageKey() {
2091                 $hash = $this->getSha1();
2092                 if ( !$hash ) {
2093                         return false;
2094                 }
2095                 $ext = $this->getExtension();
2096                 $dotExt = $ext === '' ? '' : ".$ext";
2097
2098                 return $hash . $dotExt;
2099         }
2100
2101         /**
2102          * Determine if the current user is allowed to view a particular
2103          * field of this file, if it's marked as deleted.
2104          * STUB
2105          * @param int $field
2106          * @param User $user User object to check, or null to use $wgUser
2107          * @return bool
2108          */
2109         function userCan( $field, User $user = null ) {
2110                 return true;
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
2235         /**
2236          * Whether the thumbnails created on the same server as this code is running.
2237          * @since 1.25
2238          * @return bool
2239          */
2240         public function isTransformedLocally() {
2241                 return true;
2242         }
2243 }