includes/filerepo/File.php

   1 <?php
   2 /**
   3  * Base code for files.
   4  *
   5  * @file
   6  * @ingroup FileRepo
   7  */
   8
   9 /**
  10  * Implements some public methods and some protected utility functions which
  11  * are required by multiple child classes. Contains stub functionality for
  12  * unimplemented public methods.
  13  *
  14  * Stub functions which should be overridden are marked with STUB. Some more
  15  * concrete functions are also typically overridden by child classes.
  16  *
  17  * Note that only the repo object knows what its file class is called. You should
  18  * never name a file class explictly outside of the repo class. Instead use the
  19  * repo's factory functions to generate file objects, for example:
  20  *
  21  * RepoGroup::singleton()->getLocalRepo()->newFile($title);
  22  *
  23  * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
  24  * in most cases.
  25  *
  26  * @ingroup FileRepo
  27  */
  28 abstract class File {
  29         const DELETED_FILE = 1;
  30         const DELETED_COMMENT = 2;
  31         const DELETED_USER = 4;
  32         const DELETED_RESTRICTED = 8;
  33         const RENDER_NOW = 1;
  34
  35         const DELETE_SOURCE = 1;
  36
  37         /**
  38          * Some member variables can be lazy-initialised using __get(). The
  39          * initialisation function for these variables is always a function named
  40          * like getVar(), where Var is the variable name with upper-case first
  41          * letter.
  42          *
  43          * The following variables are initialised in this way in this base class:
  44          *    name, extension, handler, path, canRender, isSafeFile,
  45          *    transformScript, hashPath, pageCount, url
  46          *
  47          * Code within this class should generally use the accessor function
  48          * directly, since __get() isn't re-entrant and therefore causes bugs that
  49          * depend on initialisation order.
  50          */
  51
  52         /**
  53          * The following member variables are not lazy-initialised
  54          */
  55
  56         /**
  57          * @var LocalRepo
  58          */
  59         var $repo;
  60
  61         /**
  62          * @var Title
  63          */
  64         var $title;
  65
  66         var $lastError, $redirected, $redirectedTitle;
  67
  68         /**
  69          * @var MediaHandler
  70          */
  71         protected $handler;
  72
  73         /**
  74          * Call this constructor from child classes
  75          */
  76         function __construct( $title, $repo ) {
  77                 $this->title = $title;
  78                 $this->repo = $repo;
  79         }
  80
  81         function __get( $name ) {
  82                 $function = array( $this, 'get' . ucfirst( $name ) );
  83                 if ( !is_callable( $function ) ) {
  84                         return null;
  85                 } else {
  86                         $this->$name = call_user_func( $function );
  87                         return $this->$name;
  88                 }
  89         }
  90
  91         /**
  92          * Normalize a file extension to the common form, and ensure it's clean.
  93          * Extensions with non-alphanumeric characters will be discarded.
  94          *
  95          * @param $ext string (without the .)
  96          * @return string
  97          */
  98         static function normalizeExtension( $ext ) {
  99                 $lower = strtolower( $ext );
 100                 $squish = array(
 101                         'htm' => 'html',
 102                         'jpeg' => 'jpg',
 103                         'mpeg' => 'mpg',
 104                         'tiff' => 'tif',
 105                         'ogv' => 'ogg' );
 106                 if( isset( $squish[$lower] ) ) {
 107                         return $squish[$lower];
 108                 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 109                         return $lower;
 110                 } else {
 111                         return '';
 112                 }
 113         }
 114
 115         /**
 116          * Checks if file extensions are compatible
 117          *
 118          * @param $old File Old file
 119          * @param $new string New name
 120          */
 121         static function checkExtensionCompatibility( File $old, $new ) {
 122                 $oldMime = $old->getMimeType();
 123                 $n = strrpos( $new, '.' );
 124                 $newExt = self::normalizeExtension(
 125                         $n ? substr( $new, $n + 1 ) : '' );
 126                 $mimeMagic = MimeMagic::singleton();
 127                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 128         }
 129
 130         /**
 131          * Upgrade the database row if there is one
 132          * Called by ImagePage
 133          * STUB
 134          */
 135         function upgradeRow() {}
 136
 137         /**
 138          * Split an internet media type into its two components; if not
 139          * a two-part name, set the minor type to 'unknown'.
 140          *
 141          * @param string $mime "text/html" etc
 142          * @return array ("text", "html") etc
 143          */
 144         public static function splitMime( $mime ) {
 145                 if( strpos( $mime, '/' ) !== false ) {
 146                         return explode( '/', $mime, 2 );
 147                 } else {
 148                         return array( $mime, 'unknown' );
 149                 }
 150         }
 151
 152         /**
 153          * Return the name of this file
 154          */
 155         public function getName() {
 156                 if ( !isset( $this->name ) ) {
 157                         $this->name = $this->repo->getNameFromTitle( $this->title );
 158                 }
 159                 return $this->name;
 160         }
 161
 162         /**
 163          * Get the file extension, e.g. "svg"
 164          */
 165         function getExtension() {
 166                 if ( !isset( $this->extension ) ) {
 167                         $n = strrpos( $this->getName(), '.' );
 168                         $this->extension = self::normalizeExtension(
 169                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 170                 }
 171                 return $this->extension;
 172         }
 173
 174         /**
 175          * Return the associated title object
 176          * @return Title
 177          */
 178         public function getTitle() { return $this->title; }
 179
 180         /**
 181          * Return the title used to find this file
 182          */
 183         public function getOriginalTitle() {
 184                 if ( $this->redirected )
 185                         return $this->getRedirectedTitle();
 186                 return $this->title;
 187         }
 188
 189         /**
 190          * Return the URL of the file
 191          */
 192         public function getUrl() {
 193                 if ( !isset( $this->url ) ) {
 194                         $this->url = $this->repo->getZoneUrl( 'public' ) . '/' . $this->getUrlRel();
 195                 }
 196                 return $this->url;
 197         }
 198
 199         /**
 200          * Return a fully-qualified URL to the file.
 201          * Upload URL paths _may or may not_ be fully qualified, so
 202          * we check. Local paths are assumed to belong on $wgServer.
 203          *
 204          * @return String
 205          */
 206         public function getFullUrl() {
 207                 return wfExpandUrl( $this->getUrl() );
 208         }
 209
 210         function getViewURL() {
 211                 if( $this->mustRender()) {
 212                         if( $this->canRender() ) {
 213                                 return $this->createThumb( $this->getWidth() );
 214                         }
 215                         else {
 216                                 wfDebug(__METHOD__.': supposed to render '.$this->getName().' ('.$this->getMimeType()."), but can't!\n");
 217                                 return $this->getURL(); #hm... return NULL?
 218                         }
 219                 } else {
 220                         return $this->getURL();
 221                 }
 222         }
 223
 224         /**
 225         * Return the full filesystem path to the file. Note that this does
 226         * not mean that a file actually exists under that location.
 227         *
 228         * This path depends on whether directory hashing is active or not,
 229         * i.e. whether the files are all found in the same directory,
 230         * or in hashed paths like /images/3/3c.
 231         *
 232         * May return false if the file is not locally accessible.
 233         */
 234         public function getPath() {
 235                 if ( !isset( $this->path ) ) {
 236                         $this->path = $this->repo->getZonePath('public') . '/' . $this->getRel();
 237                 }
 238                 return $this->path;
 239         }
 240
 241         /**
 242         * Alias for getPath()
 243         */
 244         public function getFullPath() {
 245                 return $this->getPath();
 246         }
 247
 248         /**
 249          * Return the width of the image. Returns false if the width is unknown
 250          * or undefined.
 251          *
 252          * STUB
 253          * Overridden by LocalFile, UnregisteredLocalFile
 254          */
 255         public function getWidth( $page = 1 ) { return false; }
 256
 257         /**
 258          * Return the height of the image. Returns false if the height is unknown
 259          * or undefined
 260          *
 261          * STUB
 262          * Overridden by LocalFile, UnregisteredLocalFile
 263          */
 264         public function getHeight( $page = 1 ) { return false; }
 265
 266         /**
 267          * Returns ID or name of user who uploaded the file
 268          * STUB
 269          *
 270          * @param $type string 'text' or 'id'
 271          */
 272         public function getUser( $type='text' ) { return null; }
 273
 274         /**
 275          * Get the duration of a media file in seconds
 276          */
 277         public function getLength() {
 278                 $handler = $this->getHandler();
 279                 if ( $handler ) {
 280                         return $handler->getLength( $this );
 281                 } else {
 282                         return 0;
 283                 }
 284         }
 285
 286         /**
 287          *  Return true if the file is vectorized
 288          */
 289         public function isVectorized() {
 290                 $handler = $this->getHandler();
 291                 if ( $handler ) {
 292                         return $handler->isVectorized( $this );
 293                 } else {
 294                         return false;
 295                 }
 296         }
 297
 298
 299         /**
 300          * Get handler-specific metadata
 301          * Overridden by LocalFile, UnregisteredLocalFile
 302          * STUB
 303          */
 304         public function getMetadata() { return false; }
 305
 306         /**
 307          * Return the bit depth of the file
 308          * Overridden by LocalFile
 309          * STUB
 310          */
 311         public function getBitDepth() { return 0; }
 312
 313         /**
 314          * Return the size of the image file, in bytes
 315          * Overridden by LocalFile, UnregisteredLocalFile
 316          * STUB
 317          */
 318         public function getSize() { return false; }
 319
 320         /**
 321          * Returns the mime type of the file.
 322          * Overridden by LocalFile, UnregisteredLocalFile
 323          * STUB
 324          */
 325         function getMimeType() { return 'unknown/unknown'; }
 326
 327         /**
 328          * Return the type of the media in the file.
 329          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 330          * Overridden by LocalFile,
 331          * STUB
 332          */
 333         function getMediaType() { return MEDIATYPE_UNKNOWN; }
 334
 335         /**
 336          * Checks if the output of transform() for this file is likely
 337          * to be valid. If this is false, various user elements will
 338          * display a placeholder instead.
 339          *
 340          * Currently, this checks if the file is an image format
 341          * that can be converted to a format
 342          * supported by all browsers (namely GIF, PNG and JPEG),
 343          * or if it is an SVG image and SVG conversion is enabled.
 344          */
 345         function canRender() {
 346                 if ( !isset( $this->canRender ) ) {
 347                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 348                 }
 349                 return $this->canRender;
 350         }
 351
 352         /**
 353          * Accessor for __get()
 354          */
 355         protected function getCanRender() {
 356                 return $this->canRender();
 357         }
 358
 359         /**
 360          * Return true if the file is of a type that can't be directly
 361          * rendered by typical browsers and needs to be re-rasterized.
 362          *
 363          * This returns true for everything but the bitmap types
 364          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 365          * also return true for any non-image formats.
 366          *
 367          * @return bool
 368          */
 369         function mustRender() {
 370                 return $this->getHandler() && $this->handler->mustRender( $this );
 371         }
 372
 373         /**
 374          * Alias for canRender()
 375          */
 376         function allowInlineDisplay() {
 377                 return $this->canRender();
 378         }
 379
 380         /**
 381          * Determines if this media file is in a format that is unlikely to
 382          * contain viruses or malicious content. It uses the global
 383          * $wgTrustedMediaFormats list to determine if the file is safe.
 384          *
 385          * This is used to show a warning on the description page of non-safe files.
 386          * It may also be used to disallow direct [[media:...]] links to such files.
 387          *
 388          * Note that this function will always return true if allowInlineDisplay()
 389          * or isTrustedFile() is true for this file.
 390          */
 391         function isSafeFile() {
 392                 if ( !isset( $this->isSafeFile ) ) {
 393                         $this->isSafeFile = $this->_getIsSafeFile();
 394                 }
 395                 return $this->isSafeFile;
 396         }
 397
 398         /** Accessor for __get() */
 399         protected function getIsSafeFile() {
 400                 return $this->isSafeFile();
 401         }
 402
 403         /** Uncached accessor */
 404         protected function _getIsSafeFile() {
 405                 if ($this->allowInlineDisplay()) return true;
 406                 if ($this->isTrustedFile()) return true;
 407
 408                 global $wgTrustedMediaFormats;
 409
 410                 $type= $this->getMediaType();
 411                 $mime= $this->getMimeType();
 412                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 413
 414                 if (!$type || $type===MEDIATYPE_UNKNOWN) return false; #unknown type, not trusted
 415                 if ( in_array( $type, $wgTrustedMediaFormats) ) return true;
 416
 417                 if ($mime==="unknown/unknown") return false; #unknown type, not trusted
 418                 if ( in_array( $mime, $wgTrustedMediaFormats) ) return true;
 419
 420                 return false;
 421         }
 422
 423         /** Returns true if the file is flagged as trusted. Files flagged that way
 424         * can be linked to directly, even if that is not allowed for this type of
 425         * file normally.
 426         *
 427         * This is a dummy function right now and always returns false. It could be
 428         * implemented to extract a flag from the database. The trusted flag could be
 429         * set on upload, if the user has sufficient privileges, to bypass script-
 430         * and html-filters. It may even be coupled with cryptographics signatures
 431         * or such.
 432         */
 433         function isTrustedFile() {
 434                 #this could be implemented to check a flag in the databas,
 435                 #look for signatures, etc
 436                 return false;
 437         }
 438
 439         /**
 440          * Returns true if file exists in the repository.
 441          *
 442          * Overridden by LocalFile to avoid unnecessary stat calls.
 443          *
 444          * @return boolean Whether file exists in the repository.
 445          */
 446         public function exists() {
 447                 return $this->getPath() && file_exists( $this->path );
 448         }
 449
 450         /**
 451          * Returns true if file exists in the repository and can be included in a page.
 452          * It would be unsafe to include private images, making public thumbnails inadvertently
 453          *
 454          * @return boolean Whether file exists in the repository and is includable.
 455          * @public
 456          */
 457         function isVisible() {
 458                 return $this->exists();
 459         }
 460
 461         function getTransformScript() {
 462                 if ( !isset( $this->transformScript ) ) {
 463                         $this->transformScript = false;
 464                         if ( $this->repo ) {
 465                                 $script = $this->repo->getThumbScriptUrl();
 466                                 if ( $script ) {
 467                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 468                                 }
 469                         }
 470                 }
 471                 return $this->transformScript;
 472         }
 473
 474         /**
 475          * Get a ThumbnailImage which is the same size as the source
 476          */
 477         function getUnscaledThumb( $handlerParams = array() ) {
 478                 $hp =& $handlerParams;
 479                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 480                 $width = $this->getWidth( $page );
 481                 if ( !$width ) {
 482                         return $this->iconThumb();
 483                 }
 484                 $hp['width'] = $width;
 485                 return $this->transform( $hp );
 486         }
 487
 488         /**
 489          * Return the file name of a thumbnail with the specified parameters
 490          *
 491          * @param $params Array: handler-specific parameters
 492          * @private -ish
 493          */
 494         function thumbName( $params ) {
 495                 return $this->generateThumbName( $this->getName(), $params );
 496         }
 497
 498         /**
 499          * Generate a thumbnail file name from a name and specified parameters
 500          *
 501          * @param string $name
 502          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 503          */
 504         function generateThumbName( $name, $params ) {
 505                 if ( !$this->getHandler() ) {
 506                         return null;
 507                 }
 508                 $extension = $this->getExtension();
 509                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType( $extension, $this->getMimeType(), $params );
 510                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 511                 if ( $thumbExt != $extension ) {
 512                         $thumbName .= ".$thumbExt";
 513                 }
 514                 return $thumbName;
 515         }
 516
 517         /**
 518          * Create a thumbnail of the image having the specified width/height.
 519          * The thumbnail will not be created if the width is larger than the
 520          * image's width. Let the browser do the scaling in this case.
 521          * The thumbnail is stored on disk and is only computed if the thumbnail
 522          * file does not exist OR if it is older than the image.
 523          * Returns the URL.
 524          *
 525          * Keeps aspect ratio of original image. If both width and height are
 526          * specified, the generated image will be no bigger than width x height,
 527          * and will also have correct aspect ratio.
 528          *
 529          * @param $width Integer: maximum width of the generated thumbnail
 530          * @param $height Integer: maximum height of the image (optional)
 531          */
 532         public function createThumb( $width, $height = -1 ) {
 533                 $params = array( 'width' => $width );
 534                 if ( $height != -1 ) {
 535                         $params['height'] = $height;
 536                 }
 537                 $thumb = $this->transform( $params );
 538                 if( is_null( $thumb ) || $thumb->isError() ) return '';
 539                 return $thumb->getUrl();
 540         }
 541
 542         /**
 543          * As createThumb, but returns a ThumbnailImage object. This can
 544          * provide access to the actual file, the real size of the thumb,
 545          * and can produce a convenient \<img\> tag for you.
 546          *
 547          * For non-image formats, this may return a filetype-specific icon.
 548          *
 549          * @param $width Integer: maximum width of the generated thumbnail
 550          * @param $height Integer: maximum height of the image (optional)
 551          * @param $render Integer: Deprecated
 552          *
 553          * @return ThumbnailImage or null on failure
 554          *
 555          * @deprecated use transform()
 556          */
 557         public function getThumbnail( $width, $height=-1, $render = true ) {
 558                 wfDeprecated( __METHOD__ );
 559                 $params = array( 'width' => $width );
 560                 if ( $height != -1 ) {
 561                         $params['height'] = $height;
 562                 }
 563                 return $this->transform( $params, 0 );
 564         }
 565
 566         /**
 567          * Transform a media file
 568          *
 569          * @param $params Array: an associative array of handler-specific parameters.
 570          *                Typical keys are width, height and page.
 571          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 572          * @return MediaTransformOutput | false
 573          */
 574         function transform( $params, $flags = 0 ) {
 575                 global $wgUseSquid, $wgIgnoreImageErrors, $wgThumbnailEpoch, $wgServer;
 576
 577                 wfProfileIn( __METHOD__ );
 578                 do {
 579                         if ( !$this->canRender() ) {
 580                                 // not a bitmap or renderable image, don't try.
 581                                 $thumb = $this->iconThumb();
 582                                 break;
 583                         }
 584
 585                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 586                         $descriptionUrl =  $this->getDescriptionUrl();
 587                         if ( $descriptionUrl ) {
 588                                 $params['descriptionUrl'] = $wgServer . $descriptionUrl;
 589                         }
 590
 591                         $script = $this->getTransformScript();
 592                         if ( $script && !($flags & self::RENDER_NOW) ) {
 593                                 // Use a script to transform on client request, if possible
 594                                 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
 595                                 if( $thumb ) {
 596                                         break;
 597                                 }
 598                         }
 599
 600                         $normalisedParams = $params;
 601                         $this->handler->normaliseParams( $this, $normalisedParams );
 602                         $thumbName = $this->thumbName( $normalisedParams );
 603                         $thumbPath = $this->getThumbPath( $thumbName );
 604                         $thumbUrl = $this->getThumbUrl( $thumbName );
 605
 606                         if ( $this->repo && $this->repo->canTransformVia404() && !($flags & self::RENDER_NOW ) ) {
 607                                 $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 608                                 break;
 609                         }
 610
 611                         wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
 612                         $this->migrateThumbFile( $thumbName );
 613                         if ( file_exists( $thumbPath )) {
 614                                 $thumbTime = filemtime( $thumbPath );
 615                                 if ( $thumbTime !== FALSE &&
 616                                      gmdate( 'YmdHis', $thumbTime ) >= $wgThumbnailEpoch ) {
 617
 618                                         $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 619                                         break;
 620                                 }
 621                         }
 622                         $thumb = $this->handler->doTransform( $this, $thumbPath, $thumbUrl, $params );
 623
 624                         // Ignore errors if requested
 625                         if ( !$thumb ) {
 626                                 $thumb = null;
 627                         } elseif ( $thumb->isError() ) {
 628                                 $this->lastError = $thumb->toText();
 629                                 if ( $wgIgnoreImageErrors && !($flags & self::RENDER_NOW) ) {
 630                                         $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 631                                 }
 632                         }
 633
 634                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 635                         // purge collisions from elsewhere during failure. Don't keep triggering for
 636                         // "thumbs" which have the main image URL though (bug 13776)
 637                         if ( $wgUseSquid && ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL()) ) {
 638                                 SquidUpdate::purge( array( $thumbUrl ) );
 639                         }
 640                 } while (false);
 641
 642                 wfProfileOut( __METHOD__ );
 643                 return is_object( $thumb ) ? $thumb : false;
 644         }
 645
 646         /**
 647          * Hook into transform() to allow migration of thumbnail files
 648          * STUB
 649          * Overridden by LocalFile
 650          */
 651         function migrateThumbFile( $thumbName ) {}
 652
 653         /**
 654          * Get a MediaHandler instance for this file
 655          * @return MediaHandler
 656          */
 657         function getHandler() {
 658                 if ( !isset( $this->handler ) ) {
 659                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
 660                 }
 661                 return $this->handler;
 662         }
 663
 664         /**
 665          * Get a ThumbnailImage representing a file type icon
 666          * @return ThumbnailImage
 667          */
 668         function iconThumb() {
 669                 global $wgStylePath, $wgStyleDirectory;
 670
 671                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
 672                 foreach( $try as $icon ) {
 673                         $path = '/common/images/icons/' . $icon;
 674                         $filepath = $wgStyleDirectory . $path;
 675                         if( file_exists( $filepath ) ) {
 676                                 return new ThumbnailImage( $this, $wgStylePath . $path, 120, 120 );
 677                         }
 678                 }
 679                 return null;
 680         }
 681
 682         /**
 683          * Get last thumbnailing error.
 684          * Largely obsolete.
 685          */
 686         function getLastError() {
 687                 return $this->lastError;
 688         }
 689
 690         /**
 691          * Get all thumbnail names previously generated for this file
 692          * STUB
 693          * Overridden by LocalFile
 694          */
 695         function getThumbnails() { return array(); }
 696
 697         /**
 698          * Purge shared caches such as thumbnails and DB data caching
 699          * STUB
 700          * Overridden by LocalFile
 701          */
 702         function purgeCache() {}
 703
 704         /**
 705          * Purge the file description page, but don't go after
 706          * pages using the file. Use when modifying file history
 707          * but not the current data.
 708          */
 709         function purgeDescription() {
 710                 $title = $this->getTitle();
 711                 if ( $title ) {
 712                         $title->invalidateCache();
 713                         $title->purgeSquid();
 714                 }
 715         }
 716
 717         /**
 718          * Purge metadata and all affected pages when the file is created,
 719          * deleted, or majorly updated.
 720          */
 721         function purgeEverything() {
 722                 // Delete thumbnails and refresh file metadata cache
 723                 $this->purgeCache();
 724                 $this->purgeDescription();
 725
 726                 // Purge cache of all pages using this file
 727                 $title = $this->getTitle();
 728                 if ( $title ) {
 729                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
 730                         $update->doUpdate();
 731                 }
 732         }
 733
 734         /**
 735          * Return a fragment of the history of file.
 736          *
 737          * STUB
 738          * @param $limit integer Limit of rows to return
 739          * @param $start timestamp Only revisions older than $start will be returned
 740          * @param $end timestamp Only revisions newer than $end will be returned
 741          * @param $inc bool Include the endpoints of the time range
 742          */
 743         function getHistory($limit = null, $start = null, $end = null, $inc=true) {
 744                 return array();
 745         }
 746
 747         /**
 748          * Return the history of this file, line by line. Starts with current version,
 749          * then old versions. Should return an object similar to an image/oldimage
 750          * database row.
 751          *
 752          * STUB
 753          * Overridden in LocalFile
 754          */
 755         public function nextHistoryLine() {
 756                 return false;
 757         }
 758
 759         /**
 760          * Reset the history pointer to the first element of the history.
 761          * Always call this function after using nextHistoryLine() to free db resources
 762          * STUB
 763          * Overridden in LocalFile.
 764          */
 765         public function resetHistory() {}
 766
 767         /**
 768          * Get the filename hash component of the directory including trailing slash,
 769          * e.g. f/fa/
 770          * If the repository is not hashed, returns an empty string.
 771          */
 772         function getHashPath() {
 773                 if ( !isset( $this->hashPath ) ) {
 774                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
 775                 }
 776                 return $this->hashPath;
 777         }
 778
 779         /**
 780          * Get the path of the file relative to the public zone root
 781          */
 782         function getRel() {
 783                 return $this->getHashPath() . $this->getName();
 784         }
 785
 786         /**
 787          * Get urlencoded relative path of the file
 788          */
 789         function getUrlRel() {
 790                 return $this->getHashPath() . rawurlencode( $this->getName() );
 791         }
 792
 793         /** Get the relative path for an archive file */
 794         function getArchiveRel( $suffix = false ) {
 795                 $path = 'archive/' . $this->getHashPath();
 796                 if ( $suffix === false ) {
 797                         $path = substr( $path, 0, -1 );
 798                 } else {
 799                         $path .= $suffix;
 800                 }
 801                 return $path;
 802         }
 803
 804         /** Get the path of the archive directory, or a particular file if $suffix is specified */
 805         function getArchivePath( $suffix = false ) {
 806                 return $this->repo->getZonePath('public') . '/' . $this->getArchiveRel( $suffix );
 807         }
 808
 809         /** Get the path of the thumbnail directory, or a particular file if $suffix is specified */
 810         function getThumbPath( $suffix = false ) {
 811                 $path = $this->repo->getZonePath('thumb') . '/' . $this->getRel();
 812                 if ( $suffix !== false ) {
 813                         $path .= '/' . $suffix;
 814                 }
 815                 return $path;
 816         }
 817
 818         /** Get the URL of the archive directory, or a particular file if $suffix is specified */
 819         function getArchiveUrl( $suffix = false ) {
 820                 $path = $this->repo->getZoneUrl('public') . '/archive/' . $this->getHashPath();
 821                 if ( $suffix === false ) {
 822                         $path = substr( $path, 0, -1 );
 823                 } else {
 824                         $path .= rawurlencode( $suffix );
 825                 }
 826                 return $path;
 827         }
 828
 829         /** Get the URL of the thumbnail directory, or a particular file if $suffix is specified */
 830         function getThumbUrl( $suffix = false ) {
 831                 $path = $this->repo->getZoneUrl('thumb') . '/' . $this->getUrlRel();
 832                 if ( $suffix !== false ) {
 833                         $path .= '/' . rawurlencode( $suffix );
 834                 }
 835                 return $path;
 836         }
 837
 838         /** Get the virtual URL for an archive file or directory */
 839         function getArchiveVirtualUrl( $suffix = false ) {
 840                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
 841                 if ( $suffix === false ) {
 842                         $path = substr( $path, 0, -1 );
 843                 } else {
 844                         $path .= rawurlencode( $suffix );
 845                 }
 846                 return $path;
 847         }
 848
 849         /** Get the virtual URL for a thumbnail file or directory */
 850         function getThumbVirtualUrl( $suffix = false ) {
 851                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
 852                 if ( $suffix !== false ) {
 853                         $path .= '/' . rawurlencode( $suffix );
 854                 }
 855                 return $path;
 856         }
 857
 858         /** Get the virtual URL for the file itself */
 859         function getVirtualUrl( $suffix = false ) {
 860                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
 861                 if ( $suffix !== false ) {
 862                         $path .= '/' . rawurlencode( $suffix );
 863                 }
 864                 return $path;
 865         }
 866
 867         /**
 868          * @return bool
 869          */
 870         function isHashed() {
 871                 return $this->repo->isHashed();
 872         }
 873
 874         function readOnlyError() {
 875                 throw new MWException( get_class($this) . ': write operations are not supported' );
 876         }
 877
 878         /**
 879          * Record a file upload in the upload log and the image table
 880          * STUB
 881          * Overridden by LocalFile
 882          */
 883         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
 884                 $this->readOnlyError();
 885         }
 886
 887         /**
 888          * Move or copy a file to its public location. If a file exists at the
 889          * destination, move it to an archive. Returns a FileRepoStatus object with
 890          * the archive name in the "value" member on success.
 891          *
 892          * The archive name should be passed through to recordUpload for database
 893          * registration.
 894          *
 895          * @param $srcPath String: local filesystem path to the source image
 896          * @param $flags Integer: a bitwise combination of:
 897          *     File::DELETE_SOURCE    Delete the source file, i.e. move
 898          *         rather than copy
 899          * @return FileRepoStatus object. On success, the value member contains the
 900          *     archive name, or an empty string if it was a new file.
 901          *
 902          * STUB
 903          * Overridden by LocalFile
 904          */
 905         function publish( $srcPath, $flags = 0 ) {
 906                 $this->readOnlyError();
 907         }
 908
 909         /**
 910          * Get an array of Title objects which are articles which use this file
 911          * Also adds their IDs to the link cache
 912          *
 913          * This is mostly copied from Title::getLinksTo()
 914          *
 915          * @deprecated Use HTMLCacheUpdate, this function uses too much memory
 916          */
 917         function getLinksTo( $options = array() ) {
 918                 wfDeprecated( __METHOD__ );
 919                 wfProfileIn( __METHOD__ );
 920
 921                 // Note: use local DB not repo DB, we want to know local links
 922                 if ( count( $options ) > 0 ) {
 923                         $db = wfGetDB( DB_MASTER );
 924                 } else {
 925                         $db = wfGetDB( DB_SLAVE );
 926                 }
 927                 $linkCache = LinkCache::singleton();
 928
 929                 $encName = $db->addQuotes( $this->getName() );
 930                 $res = $db->select( array( 'page', 'imagelinks'),
 931                                                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
 932                                                         array( 'page_id=il_from', 'il_to' => $encName ),
 933                                                         __METHOD__,
 934                                                         $options );
 935
 936                 $retVal = array();
 937                 if ( $db->numRows( $res ) ) {
 938                         foreach ( $res as $row ) {
 939                                 $titleObj = Title::newFromRow( $row );
 940                                 if ( $titleObj ) {
 941                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect, $row->page_latest );
 942                                         $retVal[] = $titleObj;
 943                                 }
 944                         }
 945                 }
 946                 wfProfileOut( __METHOD__ );
 947                 return $retVal;
 948         }
 949
 950         function formatMetadata() {
 951                 if ( !$this->getHandler() ) {
 952                         return false;
 953                 }
 954                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
 955         }
 956
 957         /**
 958          * Returns true if the file comes from the local file repository.
 959          *
 960          * @return bool
 961          */
 962         function isLocal() {
 963                 $repo = $this->getRepo();
 964                 return $repo && $repo->isLocal();
 965         }
 966
 967         /**
 968          * Returns the name of the repository.
 969          *
 970          * @return string
 971          */
 972         function getRepoName() {
 973                 return $this->repo ? $this->repo->getName() : 'unknown';
 974         }
 975         /*
 976          * Returns the repository
 977          */
 978         function getRepo() {
 979                 return $this->repo;
 980         }
 981
 982         /**
 983          * Returns true if the image is an old version
 984          * STUB
 985          */
 986         function isOld() {
 987                 return false;
 988         }
 989
 990         /**
 991          * Is this file a "deleted" file in a private archive?
 992          * STUB
 993          */
 994         function isDeleted( $field ) {
 995                 return false;
 996         }
 997
 998         /**
 999          * Return the deletion bitfield
1000          * STUB
1001          */
1002         function getVisibility() {
1003                 return 0;
1004         }
1005
1006         /**
1007          * Was this file ever deleted from the wiki?
1008          *
1009          * @return bool
1010          */
1011         function wasDeleted() {
1012                 $title = $this->getTitle();
1013                 return $title && $title->isDeletedQuick();
1014         }
1015
1016         /**
1017          * Move file to the new title
1018          *
1019          * Move current, old version and all thumbnails
1020          * to the new filename. Old file is deleted.
1021          *
1022          * Cache purging is done; checks for validity
1023          * and logging are caller's responsibility
1024          *
1025          * @param $target Title New file name
1026          * @return FileRepoStatus object.
1027          */
1028          function move( $target ) {
1029                 $this->readOnlyError();
1030          }
1031
1032         /**
1033          * Delete all versions of the file.
1034          *
1035          * Moves the files into an archive directory (or deletes them)
1036          * and removes the database rows.
1037          *
1038          * Cache purging is done; logging is caller's responsibility.
1039          *
1040          * @param $reason String
1041          * @param $suppress Boolean: hide content from sysops?
1042          * @return true on success, false on some kind of failure
1043          * STUB
1044          * Overridden by LocalFile
1045          */
1046         function delete( $reason, $suppress = false ) {
1047                 $this->readOnlyError();
1048         }
1049
1050         /**
1051          * Restore all or specified deleted revisions to the given file.
1052          * Permissions and logging are left to the caller.
1053          *
1054          * May throw database exceptions on error.
1055          *
1056          * @param $versions set of record ids of deleted items to restore,
1057          *                    or empty to restore all revisions.
1058          * @param $unsuppress remove restrictions on content upon restoration?
1059          * @return the number of file revisions restored if successful,
1060          *         or false on failure
1061          * STUB
1062          * Overridden by LocalFile
1063          */
1064         function restore( $versions=array(), $unsuppress=false ) {
1065                 $this->readOnlyError();
1066         }
1067
1068         /**
1069          * Returns 'true' if this file is a type which supports multiple pages,
1070          * e.g. DJVU or PDF. Note that this may be true even if the file in
1071          * question only has a single page.
1072          *
1073          * @return Bool
1074          */
1075         function isMultipage() {
1076                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1077         }
1078
1079         /**
1080          * Returns the number of pages of a multipage document, or false for
1081          * documents which aren't multipage documents
1082          */
1083         function pageCount() {
1084                 if ( !isset( $this->pageCount ) ) {
1085                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1086                                 $this->pageCount = $this->handler->pageCount( $this );
1087                         } else {
1088                                 $this->pageCount = false;
1089                         }
1090                 }
1091                 return $this->pageCount;
1092         }
1093
1094         /**
1095          * Calculate the height of a thumbnail using the source and destination width
1096          */
1097         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1098                 // Exact integer multiply followed by division
1099                 if ( $srcWidth == 0 ) {
1100                         return 0;
1101                 } else {
1102                         return round( $srcHeight * $dstWidth / $srcWidth );
1103                 }
1104         }
1105
1106         /**
1107          * Get an image size array like that returned by getImageSize(), or false if it
1108          * can't be determined.
1109          *
1110          * @param $fileName String: The filename
1111          * @return Array
1112          */
1113         function getImageSize( $fileName ) {
1114                 if ( !$this->getHandler() ) {
1115                         return false;
1116                 }
1117                 return $this->handler->getImageSize( $this, $fileName );
1118         }
1119
1120         /**
1121          * Get the URL of the image description page. May return false if it is
1122          * unknown or not applicable.
1123          */
1124         function getDescriptionUrl() {
1125                 return $this->repo->getDescriptionUrl( $this->getName() );
1126         }
1127
1128         /**
1129          * Get the HTML text of the description page, if available
1130          */
1131         function getDescriptionText() {
1132                 global $wgMemc, $wgLang;
1133                 if ( !$this->repo->fetchDescription ) {
1134                         return false;
1135                 }
1136                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1137                 if ( $renderUrl ) {
1138                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1139                                 wfDebug("Attempting to get the description from cache...");
1140                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1141                                                                         $this->getName() );
1142                                 $obj = $wgMemc->get($key);
1143                                 if ($obj) {
1144                                         wfDebug("success!\n");
1145                                         return $obj;
1146                                 }
1147                                 wfDebug("miss\n");
1148                         }
1149                         wfDebug( "Fetching shared description from $renderUrl\n" );
1150                         $res = Http::get( $renderUrl );
1151                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1152                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1153                         }
1154                         return $res;
1155                 } else {
1156                         return false;
1157                 }
1158         }
1159
1160         /**
1161          * Get discription of file revision
1162          * STUB
1163          */
1164         function getDescription() {
1165                 return null;
1166         }
1167
1168         /**
1169          * Get the 14-character timestamp of the file upload, or false if
1170          * it doesn't exist
1171          */
1172         function getTimestamp() {
1173                 $path = $this->getPath();
1174                 if ( !file_exists( $path ) ) {
1175                         return false;
1176                 }
1177                 return wfTimestamp( TS_MW, filemtime( $path ) );
1178         }
1179
1180         /**
1181          * Get the SHA-1 base 36 hash of the file
1182          */
1183         function getSha1() {
1184                 return self::sha1Base36( $this->getPath() );
1185         }
1186
1187         /**
1188          * Get the deletion archive key, <sha1>.<ext>
1189          */
1190         function getStorageKey() {
1191                 $hash = $this->getSha1();
1192                 if ( !$hash ) {
1193                         return false;
1194                 }
1195                 $ext = $this->getExtension();
1196                 $dotExt = $ext === '' ? '' : ".$ext";
1197                 return $hash . $dotExt;
1198         }
1199
1200         /**
1201          * Determine if the current user is allowed to view a particular
1202          * field of this file, if it's marked as deleted.
1203          * STUB
1204          * @param $field Integer
1205          * @return Boolean
1206          */
1207         function userCan( $field ) {
1208                 return true;
1209         }
1210
1211         /**
1212          * Get an associative array containing information about a file in the local filesystem.
1213          *
1214          * @param $path String: absolute local filesystem path
1215          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1216          *             Set it to false to ignore the extension.
1217          */
1218         static function getPropsFromPath( $path, $ext = true ) {
1219                 wfProfileIn( __METHOD__ );
1220                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1221                 $info = array(
1222                         'fileExists' => file_exists( $path ) && !is_dir( $path )
1223                 );
1224                 $gis = false;
1225                 if ( $info['fileExists'] ) {
1226                         $magic = MimeMagic::singleton();
1227
1228                         if ( $ext === true ) {
1229                                 $i = strrpos( $path, '.' );
1230                                 $ext = strtolower( $i ? substr( $path, $i + 1 ) : '' );
1231                         }
1232
1233                         # mime type according to file contents
1234                         $info['file-mime'] = $magic->guessMimeType( $path, false );
1235                         # logical mime type
1236                         $info['mime'] = $magic->improveTypeFromExtension( $info['file-mime'], $ext );
1237
1238                         list( $info['major_mime'], $info['minor_mime'] ) = self::splitMime( $info['mime'] );
1239                         $info['media_type'] = $magic->getMediaType( $path, $info['mime'] );
1240
1241                         # Get size in bytes
1242                         $info['size'] = filesize( $path );
1243
1244                         # Height, width and metadata
1245                         $handler = MediaHandler::getHandler( $info['mime'] );
1246                         if ( $handler ) {
1247                                 $tempImage = (object)array();
1248                                 $info['metadata'] = $handler->getMetadata( $tempImage, $path );
1249                                 $gis = $handler->getImageSize( $tempImage, $path, $info['metadata'] );
1250                         } else {
1251                                 $gis = false;
1252                                 $info['metadata'] = '';
1253                         }
1254                         $info['sha1'] = self::sha1Base36( $path );
1255
1256                         wfDebug(__METHOD__.": $path loaded, {$info['size']} bytes, {$info['mime']}.\n");
1257                 } else {
1258                         $info['mime'] = null;
1259                         $info['media_type'] = MEDIATYPE_UNKNOWN;
1260                         $info['metadata'] = '';
1261                         $info['sha1'] = '';
1262                         wfDebug(__METHOD__.": $path NOT FOUND!\n");
1263                 }
1264                 if( $gis ) {
1265                         # NOTE: $gis[2] contains a code for the image type. This is no longer used.
1266                         $info['width'] = $gis[0];
1267                         $info['height'] = $gis[1];
1268                         if ( isset( $gis['bits'] ) ) {
1269                                 $info['bits'] = $gis['bits'];
1270                         } else {
1271                                 $info['bits'] = 0;
1272                         }
1273                 } else {
1274                         $info['width'] = 0;
1275                         $info['height'] = 0;
1276                         $info['bits'] = 0;
1277                 }
1278                 wfProfileOut( __METHOD__ );
1279                 return $info;
1280         }
1281
1282         /**
1283          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1284          * encoding, zero padded to 31 digits.
1285          *
1286          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1287          * fairly neatly.
1288          *
1289          * Returns false on failure
1290          */
1291         static function sha1Base36( $path ) {
1292                 wfSuppressWarnings();
1293                 $hash = sha1_file( $path );
1294                 wfRestoreWarnings();
1295                 if ( $hash === false ) {
1296                         return false;
1297                 } else {
1298                         return wfBaseConvert( $hash, 16, 36, 31 );
1299                 }
1300         }
1301
1302         function getLongDesc() {
1303                 $handler = $this->getHandler();
1304                 if ( $handler ) {
1305                         return $handler->getLongDesc( $this );
1306                 } else {
1307                         return MediaHandler::getGeneralLongDesc( $this );
1308                 }
1309         }
1310
1311         function getShortDesc() {
1312                 $handler = $this->getHandler();
1313                 if ( $handler ) {
1314                         return $handler->getShortDesc( $this );
1315                 } else {
1316                         return MediaHandler::getGeneralShortDesc( $this );
1317                 }
1318         }
1319
1320         function getDimensionsString() {
1321                 $handler = $this->getHandler();
1322                 if ( $handler ) {
1323                         return $handler->getDimensionsString( $this );
1324                 } else {
1325                         return '';
1326                 }
1327         }
1328
1329         function getRedirected() {
1330                 return $this->redirected;
1331         }
1332
1333         function getRedirectedTitle() {
1334                 if ( $this->redirected ) {
1335                         if ( !$this->redirectTitle )
1336                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1337                         return $this->redirectTitle;
1338                 }
1339         }
1340
1341         function redirectedFrom( $from ) {
1342                 $this->redirected = $from;
1343         }
1344
1345         function isMissing() {
1346                 return false;
1347         }
1348 }
1349 /**
1350  * Aliases for backwards compatibility with 1.6
1351  */
1352 define( 'MW_IMG_DELETED_FILE', File::DELETED_FILE );
1353 define( 'MW_IMG_DELETED_COMMENT', File::DELETED_COMMENT );
1354 define( 'MW_IMG_DELETED_USER', File::DELETED_USER );
1355 define( 'MW_IMG_DELETED_RESTRICTED', File::DELETED_RESTRICTED );