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         * Most callers don't check the return value, but ForeignAPIFile::getPath
 233         * returns false.
 234         */
 235         public function getPath() {
 236                 if ( !isset( $this->path ) ) {
 237                         $this->path = $this->repo->getZonePath('public') . '/' . $this->getRel();
 238                 }
 239                 return $this->path;
 240         }
 241
 242         /**
 243         * Alias for getPath()
 244         *
 245         * @deprecated since 1.18 Use getPath().
 246         */
 247         public function getFullPath() {
 248                 wfDeprecated( __METHOD__ );
 249                 return $this->getPath();
 250         }
 251
 252         /**
 253          * Return the width of the image. Returns false if the width is unknown
 254          * or undefined.
 255          *
 256          * STUB
 257          * Overridden by LocalFile, UnregisteredLocalFile
 258          */
 259         public function getWidth( $page = 1 ) { return false; }
 260
 261         /**
 262          * Return the height of the image. Returns false if the height is unknown
 263          * or undefined
 264          *
 265          * STUB
 266          * Overridden by LocalFile, UnregisteredLocalFile
 267          */
 268         public function getHeight( $page = 1 ) { return false; }
 269
 270         /**
 271          * Returns ID or name of user who uploaded the file
 272          * STUB
 273          *
 274          * @param $type string 'text' or 'id'
 275          */
 276         public function getUser( $type='text' ) { return null; }
 277
 278         /**
 279          * Get the duration of a media file in seconds
 280          */
 281         public function getLength() {
 282                 $handler = $this->getHandler();
 283                 if ( $handler ) {
 284                         return $handler->getLength( $this );
 285                 } else {
 286                         return 0;
 287                 }
 288         }
 289
 290         /**
 291          *  Return true if the file is vectorized
 292          */
 293         public function isVectorized() {
 294                 $handler = $this->getHandler();
 295                 if ( $handler ) {
 296                         return $handler->isVectorized( $this );
 297                 } else {
 298                         return false;
 299                 }
 300         }
 301
 302
 303         /**
 304          * Get handler-specific metadata
 305          * Overridden by LocalFile, UnregisteredLocalFile
 306          * STUB
 307          */
 308         public function getMetadata() { return false; }
 309
 310         /**
 311         * get versioned metadata
 312         *
 313         * @param $metadata Mixed Array or String of (serialized) metadata
 314         * @param $version integer version number.
 315         * @return Array containing metadata, or what was passed to it on fail (unserializing if not array)
 316         */
 317         public function convertMetadataVersion($metadata, $version) {
 318                 $handler = $this->getHandler();
 319                 if ( !is_array( $metadata ) ) {
 320                         //just to make the return type consistant
 321                         $metadata = unserialize( $metadata );
 322                 }
 323                 if ( $handler ) {
 324                         return $handler->convertMetadataVersion( $metadata, $version );
 325                 } else {
 326                         return $metadata;
 327                 }
 328         }
 329
 330         /**
 331          * Return the bit depth of the file
 332          * Overridden by LocalFile
 333          * STUB
 334          */
 335         public function getBitDepth() { return 0; }
 336
 337         /**
 338          * Return the size of the image file, in bytes
 339          * Overridden by LocalFile, UnregisteredLocalFile
 340          * STUB
 341          */
 342         public function getSize() { return false; }
 343
 344         /**
 345          * Returns the mime type of the file.
 346          * Overridden by LocalFile, UnregisteredLocalFile
 347          * STUB
 348          */
 349         function getMimeType() { return 'unknown/unknown'; }
 350
 351         /**
 352          * Return the type of the media in the file.
 353          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 354          * Overridden by LocalFile,
 355          * STUB
 356          */
 357         function getMediaType() { return MEDIATYPE_UNKNOWN; }
 358
 359         /**
 360          * Checks if the output of transform() for this file is likely
 361          * to be valid. If this is false, various user elements will
 362          * display a placeholder instead.
 363          *
 364          * Currently, this checks if the file is an image format
 365          * that can be converted to a format
 366          * supported by all browsers (namely GIF, PNG and JPEG),
 367          * or if it is an SVG image and SVG conversion is enabled.
 368          */
 369         function canRender() {
 370                 if ( !isset( $this->canRender ) ) {
 371                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 372                 }
 373                 return $this->canRender;
 374         }
 375
 376         /**
 377          * Accessor for __get()
 378          */
 379         protected function getCanRender() {
 380                 return $this->canRender();
 381         }
 382
 383         /**
 384          * Return true if the file is of a type that can't be directly
 385          * rendered by typical browsers and needs to be re-rasterized.
 386          *
 387          * This returns true for everything but the bitmap types
 388          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 389          * also return true for any non-image formats.
 390          *
 391          * @return bool
 392          */
 393         function mustRender() {
 394                 return $this->getHandler() && $this->handler->mustRender( $this );
 395         }
 396
 397         /**
 398          * Alias for canRender()
 399          */
 400         function allowInlineDisplay() {
 401                 return $this->canRender();
 402         }
 403
 404         /**
 405          * Determines if this media file is in a format that is unlikely to
 406          * contain viruses or malicious content. It uses the global
 407          * $wgTrustedMediaFormats list to determine if the file is safe.
 408          *
 409          * This is used to show a warning on the description page of non-safe files.
 410          * It may also be used to disallow direct [[media:...]] links to such files.
 411          *
 412          * Note that this function will always return true if allowInlineDisplay()
 413          * or isTrustedFile() is true for this file.
 414          */
 415         function isSafeFile() {
 416                 if ( !isset( $this->isSafeFile ) ) {
 417                         $this->isSafeFile = $this->_getIsSafeFile();
 418                 }
 419                 return $this->isSafeFile;
 420         }
 421
 422         /** Accessor for __get() */
 423         protected function getIsSafeFile() {
 424                 return $this->isSafeFile();
 425         }
 426
 427         /** Uncached accessor */
 428         protected function _getIsSafeFile() {
 429                 if ($this->allowInlineDisplay()) return true;
 430                 if ($this->isTrustedFile()) return true;
 431
 432                 global $wgTrustedMediaFormats;
 433
 434                 $type= $this->getMediaType();
 435                 $mime= $this->getMimeType();
 436                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 437
 438                 if (!$type || $type===MEDIATYPE_UNKNOWN) return false; #unknown type, not trusted
 439                 if ( in_array( $type, $wgTrustedMediaFormats) ) return true;
 440
 441                 if ($mime==="unknown/unknown") return false; #unknown type, not trusted
 442                 if ( in_array( $mime, $wgTrustedMediaFormats) ) return true;
 443
 444                 return false;
 445         }
 446
 447         /** Returns true if the file is flagged as trusted. Files flagged that way
 448         * can be linked to directly, even if that is not allowed for this type of
 449         * file normally.
 450         *
 451         * This is a dummy function right now and always returns false. It could be
 452         * implemented to extract a flag from the database. The trusted flag could be
 453         * set on upload, if the user has sufficient privileges, to bypass script-
 454         * and html-filters. It may even be coupled with cryptographics signatures
 455         * or such.
 456         */
 457         function isTrustedFile() {
 458                 #this could be implemented to check a flag in the databas,
 459                 #look for signatures, etc
 460                 return false;
 461         }
 462
 463         /**
 464          * Returns true if file exists in the repository.
 465          *
 466          * Overridden by LocalFile to avoid unnecessary stat calls.
 467          *
 468          * @return boolean Whether file exists in the repository.
 469          */
 470         public function exists() {
 471                 return $this->getPath() && file_exists( $this->path );
 472         }
 473
 474         /**
 475          * Returns true if file exists in the repository and can be included in a page.
 476          * It would be unsafe to include private images, making public thumbnails inadvertently
 477          *
 478          * @return boolean Whether file exists in the repository and is includable.
 479          */
 480         public function isVisible() {
 481                 return $this->exists();
 482         }
 483
 484         function getTransformScript() {
 485                 if ( !isset( $this->transformScript ) ) {
 486                         $this->transformScript = false;
 487                         if ( $this->repo ) {
 488                                 $script = $this->repo->getThumbScriptUrl();
 489                                 if ( $script ) {
 490                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 491                                 }
 492                         }
 493                 }
 494                 return $this->transformScript;
 495         }
 496
 497         /**
 498          * Get a ThumbnailImage which is the same size as the source
 499          */
 500         function getUnscaledThumb( $handlerParams = array() ) {
 501                 $hp =& $handlerParams;
 502                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 503                 $width = $this->getWidth( $page );
 504                 if ( !$width ) {
 505                         return $this->iconThumb();
 506                 }
 507                 $hp['width'] = $width;
 508                 return $this->transform( $hp );
 509         }
 510
 511         /**
 512          * Return the file name of a thumbnail with the specified parameters
 513          *
 514          * @param $params Array: handler-specific parameters
 515          * @private -ish
 516          */
 517         function thumbName( $params ) {
 518                 return $this->generateThumbName( $this->getName(), $params );
 519         }
 520
 521         /**
 522          * Generate a thumbnail file name from a name and specified parameters
 523          *
 524          * @param string $name
 525          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 526          */
 527         function generateThumbName( $name, $params ) {
 528                 if ( !$this->getHandler() ) {
 529                         return null;
 530                 }
 531                 $extension = $this->getExtension();
 532                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType( $extension, $this->getMimeType(), $params );
 533                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 534                 if ( $thumbExt != $extension ) {
 535                         $thumbName .= ".$thumbExt";
 536                 }
 537                 return $thumbName;
 538         }
 539
 540         /**
 541          * Create a thumbnail of the image having the specified width/height.
 542          * The thumbnail will not be created if the width is larger than the
 543          * image's width. Let the browser do the scaling in this case.
 544          * The thumbnail is stored on disk and is only computed if the thumbnail
 545          * file does not exist OR if it is older than the image.
 546          * Returns the URL.
 547          *
 548          * Keeps aspect ratio of original image. If both width and height are
 549          * specified, the generated image will be no bigger than width x height,
 550          * and will also have correct aspect ratio.
 551          *
 552          * @param $width Integer: maximum width of the generated thumbnail
 553          * @param $height Integer: maximum height of the image (optional)
 554          */
 555         public function createThumb( $width, $height = -1 ) {
 556                 $params = array( 'width' => $width );
 557                 if ( $height != -1 ) {
 558                         $params['height'] = $height;
 559                 }
 560                 $thumb = $this->transform( $params );
 561                 if( is_null( $thumb ) || $thumb->isError() ) return '';
 562                 return $thumb->getUrl();
 563         }
 564
 565         /**
 566          * Transform a media file
 567          *
 568          * @param $params Array: an associative array of handler-specific parameters.
 569          *                Typical keys are width, height and page.
 570          * @param $flags Integer: a bitfield, may contain self::RENDER_NOW to force rendering
 571          * @return MediaTransformOutput | false
 572          */
 573         function transform( $params, $flags = 0 ) {
 574                 global $wgUseSquid, $wgIgnoreImageErrors, $wgThumbnailEpoch, $wgServer;
 575
 576                 wfProfileIn( __METHOD__ );
 577                 do {
 578                         if ( !$this->canRender() ) {
 579                                 // not a bitmap or renderable image, don't try.
 580                                 $thumb = $this->iconThumb();
 581                                 break;
 582                         }
 583
 584                         // Get the descriptionUrl to embed it as comment into the thumbnail. Bug 19791.
 585                         $descriptionUrl =  $this->getDescriptionUrl();
 586                         if ( $descriptionUrl ) {
 587                                 $params['descriptionUrl'] = $wgServer . $descriptionUrl;
 588                         }
 589
 590                         $script = $this->getTransformScript();
 591                         if ( $script && !($flags & self::RENDER_NOW) ) {
 592                                 // Use a script to transform on client request, if possible
 593                                 $thumb = $this->handler->getScriptedTransform( $this, $script, $params );
 594                                 if( $thumb ) {
 595                                         break;
 596                                 }
 597                         }
 598
 599                         $normalisedParams = $params;
 600                         $this->handler->normaliseParams( $this, $normalisedParams );
 601                         $thumbName = $this->thumbName( $normalisedParams );
 602                         $thumbPath = $this->getThumbPath( $thumbName );
 603                         $thumbUrl = $this->getThumbUrl( $thumbName );
 604
 605                         if ( $this->repo && $this->repo->canTransformVia404() && !($flags & self::RENDER_NOW ) ) {
 606                                 $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 607                                 break;
 608                         }
 609
 610                         wfDebug( __METHOD__.": Doing stat for $thumbPath\n" );
 611                         $this->migrateThumbFile( $thumbName );
 612                         if ( file_exists( $thumbPath )) {
 613                                 $thumbTime = filemtime( $thumbPath );
 614                                 if ( $thumbTime !== FALSE &&
 615                                         gmdate( 'YmdHis', $thumbTime ) >= $wgThumbnailEpoch ) {
 616
 617                                         $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 618                                         break;
 619                                 }
 620                         }
 621                         $thumb = $this->handler->doTransform( $this, $thumbPath, $thumbUrl, $params );
 622
 623                         // Ignore errors if requested
 624                         if ( !$thumb ) {
 625                                 $thumb = null;
 626                         } elseif ( $thumb->isError() ) {
 627                                 $this->lastError = $thumb->toText();
 628                                 if ( $wgIgnoreImageErrors && !($flags & self::RENDER_NOW) ) {
 629                                         $thumb = $this->handler->getTransform( $this, $thumbPath, $thumbUrl, $params );
 630                                 }
 631                         }
 632
 633                         // Purge. Useful in the event of Core -> Squid connection failure or squid
 634                         // purge collisions from elsewhere during failure. Don't keep triggering for
 635                         // "thumbs" which have the main image URL though (bug 13776)
 636                         if ( $wgUseSquid && ( !$thumb || $thumb->isError() || $thumb->getUrl() != $this->getURL()) ) {
 637                                 SquidUpdate::purge( array( $thumbUrl ) );
 638                         }
 639                 } while (false);
 640
 641                 wfProfileOut( __METHOD__ );
 642                 return is_object( $thumb ) ? $thumb : false;
 643         }
 644
 645         /**
 646          * Hook into transform() to allow migration of thumbnail files
 647          * STUB
 648          * Overridden by LocalFile
 649          */
 650         function migrateThumbFile( $thumbName ) {}
 651
 652         /**
 653          * Get a MediaHandler instance for this file
 654          * @return MediaHandler
 655          */
 656         function getHandler() {
 657                 if ( !isset( $this->handler ) ) {
 658                         $this->handler = MediaHandler::getHandler( $this->getMimeType() );
 659                 }
 660                 return $this->handler;
 661         }
 662
 663         /**
 664          * Get a ThumbnailImage representing a file type icon
 665          * @return ThumbnailImage
 666          */
 667         function iconThumb() {
 668                 global $wgStylePath, $wgStyleDirectory;
 669
 670                 $try = array( 'fileicon-' . $this->getExtension() . '.png', 'fileicon.png' );
 671                 foreach( $try as $icon ) {
 672                         $path = '/common/images/icons/' . $icon;
 673                         $filepath = $wgStyleDirectory . $path;
 674                         if( file_exists( $filepath ) ) {
 675                                 return new ThumbnailImage( $this, $wgStylePath . $path, 120, 120 );
 676                         }
 677                 }
 678                 return null;
 679         }
 680
 681         /**
 682          * Get last thumbnailing error.
 683          * Largely obsolete.
 684          */
 685         function getLastError() {
 686                 return $this->lastError;
 687         }
 688
 689         /**
 690          * Get all thumbnail names previously generated for this file
 691          * STUB
 692          * Overridden by LocalFile
 693          */
 694         function getThumbnails() { return array(); }
 695
 696         /**
 697          * Purge shared caches such as thumbnails and DB data caching
 698          * STUB
 699          * Overridden by LocalFile
 700          */
 701         function purgeCache() {}
 702
 703         /**
 704          * Purge the file description page, but don't go after
 705          * pages using the file. Use when modifying file history
 706          * but not the current data.
 707          */
 708         function purgeDescription() {
 709                 $title = $this->getTitle();
 710                 if ( $title ) {
 711                         $title->invalidateCache();
 712                         $title->purgeSquid();
 713                 }
 714         }
 715
 716         /**
 717          * Purge metadata and all affected pages when the file is created,
 718          * deleted, or majorly updated.
 719          */
 720         function purgeEverything() {
 721                 // Delete thumbnails and refresh file metadata cache
 722                 $this->purgeCache();
 723                 $this->purgeDescription();
 724
 725                 // Purge cache of all pages using this file
 726                 $title = $this->getTitle();
 727                 if ( $title ) {
 728                         $update = new HTMLCacheUpdate( $title, 'imagelinks' );
 729                         $update->doUpdate();
 730                 }
 731         }
 732
 733         /**
 734          * Return a fragment of the history of file.
 735          *
 736          * STUB
 737          * @param $limit integer Limit of rows to return
 738          * @param $start timestamp Only revisions older than $start will be returned
 739          * @param $end timestamp Only revisions newer than $end will be returned
 740          * @param $inc bool Include the endpoints of the time range
 741          */
 742         function getHistory($limit = null, $start = null, $end = null, $inc=true) {
 743                 return array();
 744         }
 745
 746         /**
 747          * Return the history of this file, line by line. Starts with current version,
 748          * then old versions. Should return an object similar to an image/oldimage
 749          * database row.
 750          *
 751          * STUB
 752          * Overridden in LocalFile
 753          */
 754         public function nextHistoryLine() {
 755                 return false;
 756         }
 757
 758         /**
 759          * Reset the history pointer to the first element of the history.
 760          * Always call this function after using nextHistoryLine() to free db resources
 761          * STUB
 762          * Overridden in LocalFile.
 763          */
 764         public function resetHistory() {}
 765
 766         /**
 767          * Get the filename hash component of the directory including trailing slash,
 768          * e.g. f/fa/
 769          * If the repository is not hashed, returns an empty string.
 770          */
 771         function getHashPath() {
 772                 if ( !isset( $this->hashPath ) ) {
 773                         $this->hashPath = $this->repo->getHashPath( $this->getName() );
 774                 }
 775                 return $this->hashPath;
 776         }
 777
 778         /**
 779          * Get the path of the file relative to the public zone root
 780          */
 781         function getRel() {
 782                 return $this->getHashPath() . $this->getName();
 783         }
 784
 785         /**
 786          * Get urlencoded relative path of the file
 787          */
 788         function getUrlRel() {
 789                 return $this->getHashPath() . rawurlencode( $this->getName() );
 790         }
 791
 792         /** Get the relative path for an archive file */
 793         function getArchiveRel( $suffix = false ) {
 794                 $path = 'archive/' . $this->getHashPath();
 795                 if ( $suffix === false ) {
 796                         $path = substr( $path, 0, -1 );
 797                 } else {
 798                         $path .= $suffix;
 799                 }
 800                 return $path;
 801         }
 802
 803         /** Get the path of the archive directory, or a particular file if $suffix is specified */
 804         function getArchivePath( $suffix = false ) {
 805                 return $this->repo->getZonePath('public') . '/' . $this->getArchiveRel( $suffix );
 806         }
 807
 808         /** Get the path of the thumbnail directory, or a particular file if $suffix is specified */
 809         function getThumbPath( $suffix = false ) {
 810                 $path = $this->repo->getZonePath('thumb') . '/' . $this->getRel();
 811                 if ( $suffix !== false ) {
 812                         $path .= '/' . $suffix;
 813                 }
 814                 return $path;
 815         }
 816
 817         /** Get the URL of the archive directory, or a particular file if $suffix is specified */
 818         function getArchiveUrl( $suffix = false ) {
 819                 $path = $this->repo->getZoneUrl('public') . '/archive/' . $this->getHashPath();
 820                 if ( $suffix === false ) {
 821                         $path = substr( $path, 0, -1 );
 822                 } else {
 823                         $path .= rawurlencode( $suffix );
 824                 }
 825                 return $path;
 826         }
 827
 828         /** Get the URL of the thumbnail directory, or a particular file if $suffix is specified */
 829         function getThumbUrl( $suffix = false ) {
 830                 $path = $this->repo->getZoneUrl('thumb') . '/' . $this->getUrlRel();
 831                 if ( $suffix !== false ) {
 832                         $path .= '/' . rawurlencode( $suffix );
 833                 }
 834                 return $path;
 835         }
 836
 837         /** Get the virtual URL for an archive file or directory */
 838         function getArchiveVirtualUrl( $suffix = false ) {
 839                 $path = $this->repo->getVirtualUrl() . '/public/archive/' . $this->getHashPath();
 840                 if ( $suffix === false ) {
 841                         $path = substr( $path, 0, -1 );
 842                 } else {
 843                         $path .= rawurlencode( $suffix );
 844                 }
 845                 return $path;
 846         }
 847
 848         /** Get the virtual URL for a thumbnail file or directory */
 849         function getThumbVirtualUrl( $suffix = false ) {
 850                 $path = $this->repo->getVirtualUrl() . '/thumb/' . $this->getUrlRel();
 851                 if ( $suffix !== false ) {
 852                         $path .= '/' . rawurlencode( $suffix );
 853                 }
 854                 return $path;
 855         }
 856
 857         /** Get the virtual URL for the file itself */
 858         function getVirtualUrl( $suffix = false ) {
 859                 $path = $this->repo->getVirtualUrl() . '/public/' . $this->getUrlRel();
 860                 if ( $suffix !== false ) {
 861                         $path .= '/' . rawurlencode( $suffix );
 862                 }
 863                 return $path;
 864         }
 865
 866         /**
 867          * @return bool
 868          */
 869         function isHashed() {
 870                 return $this->repo->isHashed();
 871         }
 872
 873         function readOnlyError() {
 874                 throw new MWException( get_class($this) . ': write operations are not supported' );
 875         }
 876
 877         /**
 878          * Record a file upload in the upload log and the image table
 879          * STUB
 880          * Overridden by LocalFile
 881          */
 882         function recordUpload( $oldver, $desc, $license = '', $copyStatus = '', $source = '', $watch = false ) {
 883                 $this->readOnlyError();
 884         }
 885
 886         /**
 887          * Move or copy a file to its public location. If a file exists at the
 888          * destination, move it to an archive. Returns a FileRepoStatus object with
 889          * the archive name in the "value" member on success.
 890          *
 891          * The archive name should be passed through to recordUpload for database
 892          * registration.
 893          *
 894          * @param $srcPath String: local filesystem path to the source image
 895          * @param $flags Integer: a bitwise combination of:
 896          *     File::DELETE_SOURCE    Delete the source file, i.e. move
 897          *         rather than copy
 898          * @return FileRepoStatus object. On success, the value member contains the
 899          *     archive name, or an empty string if it was a new file.
 900          *
 901          * STUB
 902          * Overridden by LocalFile
 903          */
 904         function publish( $srcPath, $flags = 0 ) {
 905                 $this->readOnlyError();
 906         }
 907
 908         function formatMetadata() {
 909                 if ( !$this->getHandler() ) {
 910                         return false;
 911                 }
 912                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
 913         }
 914
 915         /**
 916          * Returns true if the file comes from the local file repository.
 917          *
 918          * @return bool
 919          */
 920         function isLocal() {
 921                 $repo = $this->getRepo();
 922                 return $repo && $repo->isLocal();
 923         }
 924
 925         /**
 926          * Returns the name of the repository.
 927          *
 928          * @return string
 929          */
 930         function getRepoName() {
 931                 return $this->repo ? $this->repo->getName() : 'unknown';
 932         }
 933
 934         /*
 935          * Returns the repository
 936          */
 937         function getRepo() {
 938                 return $this->repo;
 939         }
 940
 941         /**
 942          * Returns true if the image is an old version
 943          * STUB
 944          */
 945         function isOld() {
 946                 return false;
 947         }
 948
 949         /**
 950          * Is this file a "deleted" file in a private archive?
 951          * STUB
 952          */
 953         function isDeleted( $field ) {
 954                 return false;
 955         }
 956
 957         /**
 958          * Return the deletion bitfield
 959          * STUB
 960          */
 961         function getVisibility() {
 962                 return 0;
 963         }
 964
 965         /**
 966          * Was this file ever deleted from the wiki?
 967          *
 968          * @return bool
 969          */
 970         function wasDeleted() {
 971                 $title = $this->getTitle();
 972                 return $title && $title->isDeletedQuick();
 973         }
 974
 975         /**
 976          * Move file to the new title
 977          *
 978          * Move current, old version and all thumbnails
 979          * to the new filename. Old file is deleted.
 980          *
 981          * Cache purging is done; checks for validity
 982          * and logging are caller's responsibility
 983          *
 984          * @param $target Title New file name
 985          * @return FileRepoStatus object.
 986          */
 987          function move( $target ) {
 988                 $this->readOnlyError();
 989          }
 990
 991         /**
 992          * Delete all versions of the file.
 993          *
 994          * Moves the files into an archive directory (or deletes them)
 995          * and removes the database rows.
 996          *
 997          * Cache purging is done; logging is caller's responsibility.
 998          *
 999          * @param $reason String
1000          * @param $suppress Boolean: hide content from sysops?
1001          * @return true on success, false on some kind of failure
1002          * STUB
1003          * Overridden by LocalFile
1004          */
1005         function delete( $reason, $suppress = false ) {
1006                 $this->readOnlyError();
1007         }
1008
1009         /**
1010          * Restore all or specified deleted revisions to the given file.
1011          * Permissions and logging are left to the caller.
1012          *
1013          * May throw database exceptions on error.
1014          *
1015          * @param $versions set of record ids of deleted items to restore,
1016          *                    or empty to restore all revisions.
1017          * @param $unsuppress remove restrictions on content upon restoration?
1018          * @return the number of file revisions restored if successful,
1019          *         or false on failure
1020          * STUB
1021          * Overridden by LocalFile
1022          */
1023         function restore( $versions=array(), $unsuppress=false ) {
1024                 $this->readOnlyError();
1025         }
1026
1027         /**
1028          * Returns 'true' if this file is a type which supports multiple pages,
1029          * e.g. DJVU or PDF. Note that this may be true even if the file in
1030          * question only has a single page.
1031          *
1032          * @return Bool
1033          */
1034         function isMultipage() {
1035                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1036         }
1037
1038         /**
1039          * Returns the number of pages of a multipage document, or false for
1040          * documents which aren't multipage documents
1041          */
1042         function pageCount() {
1043                 if ( !isset( $this->pageCount ) ) {
1044                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1045                                 $this->pageCount = $this->handler->pageCount( $this );
1046                         } else {
1047                                 $this->pageCount = false;
1048                         }
1049                 }
1050                 return $this->pageCount;
1051         }
1052
1053         /**
1054          * Calculate the height of a thumbnail using the source and destination width
1055          */
1056         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1057                 // Exact integer multiply followed by division
1058                 if ( $srcWidth == 0 ) {
1059                         return 0;
1060                 } else {
1061                         return round( $srcHeight * $dstWidth / $srcWidth );
1062                 }
1063         }
1064
1065         /**
1066          * Get an image size array like that returned by getImageSize(), or false if it
1067          * can't be determined.
1068          *
1069          * @param $fileName String: The filename
1070          * @return Array
1071          */
1072         function getImageSize( $fileName ) {
1073                 if ( !$this->getHandler() ) {
1074                         return false;
1075                 }
1076                 return $this->handler->getImageSize( $this, $fileName );
1077         }
1078
1079         /**
1080          * Get the URL of the image description page. May return false if it is
1081          * unknown or not applicable.
1082          */
1083         function getDescriptionUrl() {
1084                 return $this->repo->getDescriptionUrl( $this->getName() );
1085         }
1086
1087         /**
1088          * Get the HTML text of the description page, if available
1089          */
1090         function getDescriptionText() {
1091                 global $wgMemc, $wgLang;
1092                 if ( !$this->repo->fetchDescription ) {
1093                         return false;
1094                 }
1095                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1096                 if ( $renderUrl ) {
1097                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1098                                 wfDebug("Attempting to get the description from cache...");
1099                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1100                                                                         $this->getName() );
1101                                 $obj = $wgMemc->get($key);
1102                                 if ($obj) {
1103                                         wfDebug("success!\n");
1104                                         return $obj;
1105                                 }
1106                                 wfDebug("miss\n");
1107                         }
1108                         wfDebug( "Fetching shared description from $renderUrl\n" );
1109                         $res = Http::get( $renderUrl );
1110                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1111                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1112                         }
1113                         return $res;
1114                 } else {
1115                         return false;
1116                 }
1117         }
1118
1119         /**
1120          * Get discription of file revision
1121          * STUB
1122          */
1123         function getDescription() {
1124                 return null;
1125         }
1126
1127         /**
1128          * Get the 14-character timestamp of the file upload, or false if
1129          * it doesn't exist
1130          */
1131         function getTimestamp() {
1132                 $path = $this->getPath();
1133                 if ( !file_exists( $path ) ) {
1134                         return false;
1135                 }
1136                 return wfTimestamp( TS_MW, filemtime( $path ) );
1137         }
1138
1139         /**
1140          * Get the SHA-1 base 36 hash of the file
1141          */
1142         function getSha1() {
1143                 return self::sha1Base36( $this->getPath() );
1144         }
1145
1146         /**
1147          * Get the deletion archive key, <sha1>.<ext>
1148          */
1149         function getStorageKey() {
1150                 $hash = $this->getSha1();
1151                 if ( !$hash ) {
1152                         return false;
1153                 }
1154                 $ext = $this->getExtension();
1155                 $dotExt = $ext === '' ? '' : ".$ext";
1156                 return $hash . $dotExt;
1157         }
1158
1159         /**
1160          * Determine if the current user is allowed to view a particular
1161          * field of this file, if it's marked as deleted.
1162          * STUB
1163          * @param $field Integer
1164          * @return Boolean
1165          */
1166         function userCan( $field ) {
1167                 return true;
1168         }
1169
1170         /**
1171          * Get an associative array containing information about a file in the local filesystem.
1172          *
1173          * @param $path String: absolute local filesystem path
1174          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1175          *             Set it to false to ignore the extension.
1176          */
1177         static function getPropsFromPath( $path, $ext = true ) {
1178                 wfProfileIn( __METHOD__ );
1179                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1180                 $info = array(
1181                         'fileExists' => file_exists( $path ) && !is_dir( $path )
1182                 );
1183                 $gis = false;
1184                 if ( $info['fileExists'] ) {
1185                         $magic = MimeMagic::singleton();
1186
1187                         if ( $ext === true ) {
1188                                 $i = strrpos( $path, '.' );
1189                                 $ext = strtolower( $i ? substr( $path, $i + 1 ) : '' );
1190                         }
1191
1192                         # mime type according to file contents
1193                         $info['file-mime'] = $magic->guessMimeType( $path, false );
1194                         # logical mime type
1195                         $info['mime'] = $magic->improveTypeFromExtension( $info['file-mime'], $ext );
1196
1197                         list( $info['major_mime'], $info['minor_mime'] ) = self::splitMime( $info['mime'] );
1198                         $info['media_type'] = $magic->getMediaType( $path, $info['mime'] );
1199
1200                         # Get size in bytes
1201                         $info['size'] = filesize( $path );
1202
1203                         # Height, width and metadata
1204                         $handler = MediaHandler::getHandler( $info['mime'] );
1205                         if ( $handler ) {
1206                                 $tempImage = (object)array();
1207                                 $info['metadata'] = $handler->getMetadata( $tempImage, $path );
1208                                 $gis = $handler->getImageSize( $tempImage, $path, $info['metadata'] );
1209                         } else {
1210                                 $gis = false;
1211                                 $info['metadata'] = '';
1212                         }
1213                         $info['sha1'] = self::sha1Base36( $path );
1214
1215                         wfDebug(__METHOD__.": $path loaded, {$info['size']} bytes, {$info['mime']}.\n");
1216                 } else {
1217                         $info['mime'] = null;
1218                         $info['media_type'] = MEDIATYPE_UNKNOWN;
1219                         $info['metadata'] = '';
1220                         $info['sha1'] = '';
1221                         wfDebug(__METHOD__.": $path NOT FOUND!\n");
1222                 }
1223                 if( $gis ) {
1224                         # NOTE: $gis[2] contains a code for the image type. This is no longer used.
1225                         $info['width'] = $gis[0];
1226                         $info['height'] = $gis[1];
1227                         if ( isset( $gis['bits'] ) ) {
1228                                 $info['bits'] = $gis['bits'];
1229                         } else {
1230                                 $info['bits'] = 0;
1231                         }
1232                 } else {
1233                         $info['width'] = 0;
1234                         $info['height'] = 0;
1235                         $info['bits'] = 0;
1236                 }
1237                 wfProfileOut( __METHOD__ );
1238                 return $info;
1239         }
1240
1241         /**
1242          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1243          * encoding, zero padded to 31 digits.
1244          *
1245          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1246          * fairly neatly.
1247          *
1248          * Returns false on failure
1249          */
1250         static function sha1Base36( $path ) {
1251                 wfSuppressWarnings();
1252                 $hash = sha1_file( $path );
1253                 wfRestoreWarnings();
1254                 if ( $hash === false ) {
1255                         return false;
1256                 } else {
1257                         return wfBaseConvert( $hash, 16, 36, 31 );
1258                 }
1259         }
1260
1261         function getLongDesc() {
1262                 $handler = $this->getHandler();
1263                 if ( $handler ) {
1264                         return $handler->getLongDesc( $this );
1265                 } else {
1266                         return MediaHandler::getGeneralLongDesc( $this );
1267                 }
1268         }
1269
1270         function getShortDesc() {
1271                 $handler = $this->getHandler();
1272                 if ( $handler ) {
1273                         return $handler->getShortDesc( $this );
1274                 } else {
1275                         return MediaHandler::getGeneralShortDesc( $this );
1276                 }
1277         }
1278
1279         function getDimensionsString() {
1280                 $handler = $this->getHandler();
1281                 if ( $handler ) {
1282                         return $handler->getDimensionsString( $this );
1283                 } else {
1284                         return '';
1285                 }
1286         }
1287
1288         function getRedirected() {
1289                 return $this->redirected;
1290         }
1291
1292         function getRedirectedTitle() {
1293                 if ( $this->redirected ) {
1294                         if ( !$this->redirectTitle ) {
1295                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1296                         }
1297                         return $this->redirectTitle;
1298                 }
1299         }
1300
1301         function redirectedFrom( $from ) {
1302                 $this->redirected = $from;
1303         }
1304
1305         function isMissing() {
1306                 return false;
1307         }
1308 }
1309 /**
1310  * Aliases for backwards compatibility with 1.6
1311  */
1312 define( 'MW_IMG_DELETED_FILE', File::DELETED_FILE );
1313 define( 'MW_IMG_DELETED_COMMENT', File::DELETED_COMMENT );
1314 define( 'MW_IMG_DELETED_USER', File::DELETED_USER );
1315 define( 'MW_IMG_DELETED_RESTRICTED', File::DELETED_RESTRICTED );