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