includes/filerepo/File.php

   1 <?php
   2 /**
   3  * Base code for files.
   4  *
   5  * @file
   6  * @ingroup FileRepo
   7  */
   8
   9 /**
  10  * Implements some public methods and some protected utility functions which
  11  * are required by multiple child classes. Contains stub functionality for
  12  * unimplemented public methods.
  13  *
  14  * Stub functions which should be overridden are marked with STUB. Some more
  15  * concrete functions are also typically overridden by child classes.
  16  *
  17  * Note that only the repo object knows what its file class is called. You should
  18  * never name a file class explictly outside of the repo class. Instead use the
  19  * repo's factory functions to generate file objects, for example:
  20  *
  21  * RepoGroup::singleton()->getLocalRepo()->newFile($title);
  22  *
  23  * The convenience functions wfLocalFile() and wfFindFile() should be sufficient
  24  * in most cases.
  25  *
  26  * @ingroup FileRepo
  27  */
  28 abstract class File {
  29         const DELETED_FILE = 1;
  30         const DELETED_COMMENT = 2;
  31         const DELETED_USER = 4;
  32         const DELETED_RESTRICTED = 8;
  33         const RENDER_NOW = 1;
  34
  35         const DELETE_SOURCE = 1;
  36
  37         /**
  38          * Some member variables can be lazy-initialised using __get(). The
  39          * initialisation function for these variables is always a function named
  40          * like getVar(), where Var is the variable name with upper-case first
  41          * letter.
  42          *
  43          * The following variables are initialised in this way in this base class:
  44          *    name, extension, handler, path, canRender, isSafeFile,
  45          *    transformScript, hashPath, pageCount, url
  46          *
  47          * Code within this class should generally use the accessor function
  48          * directly, since __get() isn't re-entrant and therefore causes bugs that
  49          * depend on initialisation order.
  50          */
  51
  52         /**
  53          * The following member variables are not lazy-initialised
  54          */
  55
  56         /**
  57          * @var LocalRepo
  58          */
  59         var $repo;
  60
  61         /**
  62          * @var Title
  63          */
  64         var $title;
  65
  66         var $lastError, $redirected, $redirectedTitle;
  67
  68         /**
  69          * @var MediaHandler
  70          */
  71         protected $handler;
  72
  73         /**
  74          * Call this constructor from child classes
  75          */
  76         function __construct( $title, $repo ) {
  77                 $this->title = $title;
  78                 $this->repo = $repo;
  79         }
  80
  81         function __get( $name ) {
  82                 $function = array( $this, 'get' . ucfirst( $name ) );
  83                 if ( !is_callable( $function ) ) {
  84                         return null;
  85                 } else {
  86                         $this->$name = call_user_func( $function );
  87                         return $this->$name;
  88                 }
  89         }
  90
  91         /**
  92          * Normalize a file extension to the common form, and ensure it's clean.
  93          * Extensions with non-alphanumeric characters will be discarded.
  94          *
  95          * @param $ext string (without the .)
  96          * @return string
  97          */
  98         static function normalizeExtension( $ext ) {
  99                 $lower = strtolower( $ext );
 100                 $squish = array(
 101                         'htm' => 'html',
 102                         'jpeg' => 'jpg',
 103                         'mpeg' => 'mpg',
 104                         'tiff' => 'tif',
 105                         'ogv' => 'ogg' );
 106                 if( isset( $squish[$lower] ) ) {
 107                         return $squish[$lower];
 108                 } elseif( preg_match( '/^[0-9a-z]+$/', $lower ) ) {
 109                         return $lower;
 110                 } else {
 111                         return '';
 112                 }
 113         }
 114
 115         /**
 116          * Checks if file extensions are compatible
 117          *
 118          * @param $old File Old file
 119          * @param $new string New name
 120          */
 121         static function checkExtensionCompatibility( File $old, $new ) {
 122                 $oldMime = $old->getMimeType();
 123                 $n = strrpos( $new, '.' );
 124                 $newExt = self::normalizeExtension(
 125                         $n ? substr( $new, $n + 1 ) : '' );
 126                 $mimeMagic = MimeMagic::singleton();
 127                 return $mimeMagic->isMatchingExtension( $newExt, $oldMime );
 128         }
 129
 130         /**
 131          * Upgrade the database row if there is one
 132          * Called by ImagePage
 133          * STUB
 134          */
 135         function upgradeRow() {}
 136
 137         /**
 138          * Split an internet media type into its two components; if not
 139          * a two-part name, set the minor type to 'unknown'.
 140          *
 141          * @param string $mime "text/html" etc
 142          * @return array ("text", "html") etc
 143          */
 144         public static function splitMime( $mime ) {
 145                 if( strpos( $mime, '/' ) !== false ) {
 146                         return explode( '/', $mime, 2 );
 147                 } else {
 148                         return array( $mime, 'unknown' );
 149                 }
 150         }
 151
 152         /**
 153          * Return the name of this file
 154          */
 155         public function getName() {
 156                 if ( !isset( $this->name ) ) {
 157                         $this->name = $this->repo->getNameFromTitle( $this->title );
 158                 }
 159                 return $this->name;
 160         }
 161
 162         /**
 163          * Get the file extension, e.g. "svg"
 164          */
 165         function getExtension() {
 166                 if ( !isset( $this->extension ) ) {
 167                         $n = strrpos( $this->getName(), '.' );
 168                         $this->extension = self::normalizeExtension(
 169                                 $n ? substr( $this->getName(), $n + 1 ) : '' );
 170                 }
 171                 return $this->extension;
 172         }
 173
 174         /**
 175          * Return the associated title object
 176          * @return Title
 177          */
 178         public function getTitle() { return $this->title; }
 179
 180         /**
 181          * Return the title used to find this file
 182          */
 183         public function getOriginalTitle() {
 184                 if ( $this->redirected )
 185                         return $this->getRedirectedTitle();
 186                 return $this->title;
 187         }
 188
 189         /**
 190          * Return the URL of the file
 191          */
 192         public function getUrl() {
 193                 if ( !isset( $this->url ) ) {
 194                         $this->url = $this->repo->getZoneUrl( 'public' ) . '/' . $this->getUrlRel();
 195                 }
 196                 return $this->url;
 197         }
 198
 199         /**
 200          * Return a fully-qualified URL to the file.
 201          * Upload URL paths _may or may not_ be fully qualified, so
 202          * we check. Local paths are assumed to belong on $wgServer.
 203          *
 204          * @return String
 205          */
 206         public function getFullUrl() {
 207                 return wfExpandUrl( $this->getUrl() );
 208         }
 209
 210         function getViewURL() {
 211                 if( $this->mustRender()) {
 212                         if( $this->canRender() ) {
 213                                 return $this->createThumb( $this->getWidth() );
 214                         }
 215                         else {
 216                                 wfDebug(__METHOD__.': supposed to render '.$this->getName().' ('.$this->getMimeType()."), but can't!\n");
 217                                 return $this->getURL(); #hm... return NULL?
 218                         }
 219                 } else {
 220                         return $this->getURL();
 221                 }
 222         }
 223
 224         /**
 225         * Return the full filesystem path to the file. Note that this does
 226         * not mean that a file actually exists under that location.
 227         *
 228         * This path depends on whether directory hashing is active or not,
 229         * i.e. whether the files are all found in the same directory,
 230         * or in hashed paths like /images/3/3c.
 231         *
 232         * May return false if the file is not locally accessible.
 233         */
 234         public function getPath() {
 235                 if ( !isset( $this->path ) ) {
 236                         $this->path = $this->repo->getZonePath('public') . '/' . $this->getRel();
 237                 }
 238                 return $this->path;
 239         }
 240
 241         /**
 242         * Alias for getPath()
 243         */
 244         public function getFullPath() {
 245                 return $this->getPath();
 246         }
 247
 248         /**
 249          * Return the width of the image. Returns false if the width is unknown
 250          * or undefined.
 251          *
 252          * STUB
 253          * Overridden by LocalFile, UnregisteredLocalFile
 254          */
 255         public function getWidth( $page = 1 ) { return false; }
 256
 257         /**
 258          * Return the height of the image. Returns false if the height is unknown
 259          * or undefined
 260          *
 261          * STUB
 262          * Overridden by LocalFile, UnregisteredLocalFile
 263          */
 264         public function getHeight( $page = 1 ) { return false; }
 265
 266         /**
 267          * Returns ID or name of user who uploaded the file
 268          * STUB
 269          *
 270          * @param $type string 'text' or 'id'
 271          */
 272         public function getUser( $type='text' ) { return null; }
 273
 274         /**
 275          * Get the duration of a media file in seconds
 276          */
 277         public function getLength() {
 278                 $handler = $this->getHandler();
 279                 if ( $handler ) {
 280                         return $handler->getLength( $this );
 281                 } else {
 282                         return 0;
 283                 }
 284         }
 285
 286         /**
 287          *  Return true if the file is vectorized
 288          */
 289         public function isVectorized() {
 290                 $handler = $this->getHandler();
 291                 if ( $handler ) {
 292                         return $handler->isVectorized( $this );
 293                 } else {
 294                         return false;
 295                 }
 296         }
 297
 298
 299         /**
 300          * Get handler-specific metadata
 301          * Overridden by LocalFile, UnregisteredLocalFile
 302          * STUB
 303          */
 304         public function getMetadata() { return false; }
 305
 306         /**
 307          * Return the bit depth of the file
 308          * Overridden by LocalFile
 309          * STUB
 310          */
 311         public function getBitDepth() { return 0; }
 312
 313         /**
 314          * Return the size of the image file, in bytes
 315          * Overridden by LocalFile, UnregisteredLocalFile
 316          * STUB
 317          */
 318         public function getSize() { return false; }
 319
 320         /**
 321          * Returns the mime type of the file.
 322          * Overridden by LocalFile, UnregisteredLocalFile
 323          * STUB
 324          */
 325         function getMimeType() { return 'unknown/unknown'; }
 326
 327         /**
 328          * Return the type of the media in the file.
 329          * Use the value returned by this function with the MEDIATYPE_xxx constants.
 330          * Overridden by LocalFile,
 331          * STUB
 332          */
 333         function getMediaType() { return MEDIATYPE_UNKNOWN; }
 334
 335         /**
 336          * Checks if the output of transform() for this file is likely
 337          * to be valid. If this is false, various user elements will
 338          * display a placeholder instead.
 339          *
 340          * Currently, this checks if the file is an image format
 341          * that can be converted to a format
 342          * supported by all browsers (namely GIF, PNG and JPEG),
 343          * or if it is an SVG image and SVG conversion is enabled.
 344          */
 345         function canRender() {
 346                 if ( !isset( $this->canRender ) ) {
 347                         $this->canRender = $this->getHandler() && $this->handler->canRender( $this );
 348                 }
 349                 return $this->canRender;
 350         }
 351
 352         /**
 353          * Accessor for __get()
 354          */
 355         protected function getCanRender() {
 356                 return $this->canRender();
 357         }
 358
 359         /**
 360          * Return true if the file is of a type that can't be directly
 361          * rendered by typical browsers and needs to be re-rasterized.
 362          *
 363          * This returns true for everything but the bitmap types
 364          * supported by all browsers, i.e. JPEG; GIF and PNG. It will
 365          * also return true for any non-image formats.
 366          *
 367          * @return bool
 368          */
 369         function mustRender() {
 370                 return $this->getHandler() && $this->handler->mustRender( $this );
 371         }
 372
 373         /**
 374          * Alias for canRender()
 375          */
 376         function allowInlineDisplay() {
 377                 return $this->canRender();
 378         }
 379
 380         /**
 381          * Determines if this media file is in a format that is unlikely to
 382          * contain viruses or malicious content. It uses the global
 383          * $wgTrustedMediaFormats list to determine if the file is safe.
 384          *
 385          * This is used to show a warning on the description page of non-safe files.
 386          * It may also be used to disallow direct [[media:...]] links to such files.
 387          *
 388          * Note that this function will always return true if allowInlineDisplay()
 389          * or isTrustedFile() is true for this file.
 390          */
 391         function isSafeFile() {
 392                 if ( !isset( $this->isSafeFile ) ) {
 393                         $this->isSafeFile = $this->_getIsSafeFile();
 394                 }
 395                 return $this->isSafeFile;
 396         }
 397
 398         /** Accessor for __get() */
 399         protected function getIsSafeFile() {
 400                 return $this->isSafeFile();
 401         }
 402
 403         /** Uncached accessor */
 404         protected function _getIsSafeFile() {
 405                 if ($this->allowInlineDisplay()) return true;
 406                 if ($this->isTrustedFile()) return true;
 407
 408                 global $wgTrustedMediaFormats;
 409
 410                 $type= $this->getMediaType();
 411                 $mime= $this->getMimeType();
 412                 #wfDebug("LocalFile::isSafeFile: type= $type, mime= $mime\n");
 413
 414                 if (!$type || $type===MEDIATYPE_UNKNOWN) return false; #unknown type, not trusted
 415                 if ( in_array( $type, $wgTrustedMediaFormats) ) return true;
 416
 417                 if ($mime==="unknown/unknown") return false; #unknown type, not trusted
 418                 if ( in_array( $mime, $wgTrustedMediaFormats) ) return true;
 419
 420                 return false;
 421         }
 422
 423         /** Returns true if the file is flagged as trusted. Files flagged that way
 424         * can be linked to directly, even if that is not allowed for this type of
 425         * file normally.
 426         *
 427         * This is a dummy function right now and always returns false. It could be
 428         * implemented to extract a flag from the database. The trusted flag could be
 429         * set on upload, if the user has sufficient privileges, to bypass script-
 430         * and html-filters. It may even be coupled with cryptographics signatures
 431         * or such.
 432         */
 433         function isTrustedFile() {
 434                 #this could be implemented to check a flag in the databas,
 435                 #look for signatures, etc
 436                 return false;
 437         }
 438
 439         /**
 440          * Returns true if file exists in the repository.
 441          *
 442          * Overridden by LocalFile to avoid unnecessary stat calls.
 443          *
 444          * @return boolean Whether file exists in the repository.
 445          */
 446         public function exists() {
 447                 return $this->getPath() && file_exists( $this->path );
 448         }
 449
 450         /**
 451          * Returns true if file exists in the repository and can be included in a page.
 452          * It would be unsafe to include private images, making public thumbnails inadvertently
 453          *
 454          * @return boolean Whether file exists in the repository and is includable.
 455          */
 456         public function isVisible() {
 457                 return $this->exists();
 458         }
 459
 460         function getTransformScript() {
 461                 if ( !isset( $this->transformScript ) ) {
 462                         $this->transformScript = false;
 463                         if ( $this->repo ) {
 464                                 $script = $this->repo->getThumbScriptUrl();
 465                                 if ( $script ) {
 466                                         $this->transformScript = "$script?f=" . urlencode( $this->getName() );
 467                                 }
 468                         }
 469                 }
 470                 return $this->transformScript;
 471         }
 472
 473         /**
 474          * Get a ThumbnailImage which is the same size as the source
 475          */
 476         function getUnscaledThumb( $handlerParams = array() ) {
 477                 $hp =& $handlerParams;
 478                 $page = isset( $hp['page'] ) ? $hp['page'] : false;
 479                 $width = $this->getWidth( $page );
 480                 if ( !$width ) {
 481                         return $this->iconThumb();
 482                 }
 483                 $hp['width'] = $width;
 484                 return $this->transform( $hp );
 485         }
 486
 487         /**
 488          * Return the file name of a thumbnail with the specified parameters
 489          *
 490          * @param $params Array: handler-specific parameters
 491          * @private -ish
 492          */
 493         function thumbName( $params ) {
 494                 return $this->generateThumbName( $this->getName(), $params );
 495         }
 496
 497         /**
 498          * Generate a thumbnail file name from a name and specified parameters
 499          *
 500          * @param string $name
 501          * @param array $params Parameters which will be passed to MediaHandler::makeParamString
 502          */
 503         function generateThumbName( $name, $params ) {
 504                 if ( !$this->getHandler() ) {
 505                         return null;
 506                 }
 507                 $extension = $this->getExtension();
 508                 list( $thumbExt, $thumbMime ) = $this->handler->getThumbType( $extension, $this->getMimeType(), $params );
 509                 $thumbName = $this->handler->makeParamString( $params ) . '-' . $name;
 510                 if ( $thumbExt != $extension ) {
 511                         $thumbName .= ".$thumbExt";
 512                 }
 513                 return $thumbName;
 514         }
 515
 516         /**
 517          * Create a thumbnail of the image having the specified width/height.
 518          * The thumbnail will not be created if the width is larger than the
 519          * image's width. Let the browser do the scaling in this case.
 520          * The thumbnail is stored on disk and is only computed if the thumbnail
 521          * file does not exist OR if it is older than the image.
 522          * Returns the URL.
 523          *
 524          * Keeps aspect ratio of original image. If both width and height are
 525          * specified, the generated image will be no bigger than width x height,
 526          * and will also have correct aspect ratio.
 527          *
 528          * @param $width Integer: maximum width of the generated thumbnail
 529          * @param $height Integer: maximum height of the image (optional)
 530          */
 531         public function createThumb( $width, $height = -1 ) {
 532                 $params = array( 'width' => $width );
 533                 if ( $height != -1 ) {
 534                         $params['height'] = $height;
 535                 }
 536                 $thumb = $this->transform( $params );
 537                 if( is_null( $thumb ) || $thumb->isError() ) return '';
 538                 return $thumb->getUrl();
 539         }
 540
 541         /**
 542          * As createThumb, but returns a ThumbnailImage object. This can
 543          * provide access to the actual file, the real size of the thumb,
 544          * and can produce a convenient \<img\> tag for you.
 545          *
 546          * For non-image formats, this may return a filetype-specific icon.
 547          *
 548          * @param $width Integer: maximum width of the generated thumbnail
 549          * @param $height Integer: maximum height of the image (optional)
 550          * @param $render Integer: Deprecated
 551          *
 552          * @return ThumbnailImage or null on failure
 553          *
 554          * @deprecated use transform()
 555          */
 556         public function getThumbnail( $width, $height=-1, $render = true ) {
 557                 wfDeprecated( __METHOD__ );
 558                 $params = array( 'width' => $width );
 559                 if ( $height != -1 ) {
 560                         $params['height'] = $height;
 561                 }
 562                 return $this->transform( $params, 0 );
 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         /**
 909          * Get an array of Title objects which are articles which use this file
 910          * Also adds their IDs to the link cache
 911          *
 912          * This is mostly copied from Title::getLinksTo()
 913          *
 914          * @deprecated Use HTMLCacheUpdate, this function uses too much memory
 915          */
 916         function getLinksTo( $options = array() ) {
 917                 wfDeprecated( __METHOD__ );
 918                 wfProfileIn( __METHOD__ );
 919
 920                 // Note: use local DB not repo DB, we want to know local links
 921                 if ( count( $options ) > 0 ) {
 922                         $db = wfGetDB( DB_MASTER );
 923                 } else {
 924                         $db = wfGetDB( DB_SLAVE );
 925                 }
 926                 $linkCache = LinkCache::singleton();
 927
 928                 $encName = $db->addQuotes( $this->getName() );
 929                 $res = $db->select( array( 'page', 'imagelinks'),
 930                                                         array( 'page_namespace', 'page_title', 'page_id', 'page_len', 'page_is_redirect', 'page_latest' ),
 931                                                         array( 'page_id=il_from', 'il_to' => $encName ),
 932                                                         __METHOD__,
 933                                                         $options );
 934
 935                 $retVal = array();
 936                 if ( $db->numRows( $res ) ) {
 937                         foreach ( $res as $row ) {
 938                                 $titleObj = Title::newFromRow( $row );
 939                                 if ( $titleObj ) {
 940                                         $linkCache->addGoodLinkObj( $row->page_id, $titleObj, $row->page_len, $row->page_is_redirect, $row->page_latest );
 941                                         $retVal[] = $titleObj;
 942                                 }
 943                         }
 944                 }
 945                 wfProfileOut( __METHOD__ );
 946                 return $retVal;
 947         }
 948
 949         function formatMetadata() {
 950                 if ( !$this->getHandler() ) {
 951                         return false;
 952                 }
 953                 return $this->getHandler()->formatMetadata( $this, $this->getMetadata() );
 954         }
 955
 956         /**
 957          * Returns true if the file comes from the local file repository.
 958          *
 959          * @return bool
 960          */
 961         function isLocal() {
 962                 $repo = $this->getRepo();
 963                 return $repo && $repo->isLocal();
 964         }
 965
 966         /**
 967          * Returns the name of the repository.
 968          *
 969          * @return string
 970          */
 971         function getRepoName() {
 972                 return $this->repo ? $this->repo->getName() : 'unknown';
 973         }
 974         /*
 975          * Returns the repository
 976          */
 977         function getRepo() {
 978                 return $this->repo;
 979         }
 980
 981         /**
 982          * Returns true if the image is an old version
 983          * STUB
 984          */
 985         function isOld() {
 986                 return false;
 987         }
 988
 989         /**
 990          * Is this file a "deleted" file in a private archive?
 991          * STUB
 992          */
 993         function isDeleted( $field ) {
 994                 return false;
 995         }
 996
 997         /**
 998          * Return the deletion bitfield
 999          * STUB
1000          */
1001         function getVisibility() {
1002                 return 0;
1003         }
1004
1005         /**
1006          * Was this file ever deleted from the wiki?
1007          *
1008          * @return bool
1009          */
1010         function wasDeleted() {
1011                 $title = $this->getTitle();
1012                 return $title && $title->isDeletedQuick();
1013         }
1014
1015         /**
1016          * Move file to the new title
1017          *
1018          * Move current, old version and all thumbnails
1019          * to the new filename. Old file is deleted.
1020          *
1021          * Cache purging is done; checks for validity
1022          * and logging are caller's responsibility
1023          *
1024          * @param $target Title New file name
1025          * @return FileRepoStatus object.
1026          */
1027          function move( $target ) {
1028                 $this->readOnlyError();
1029          }
1030
1031         /**
1032          * Delete all versions of the file.
1033          *
1034          * Moves the files into an archive directory (or deletes them)
1035          * and removes the database rows.
1036          *
1037          * Cache purging is done; logging is caller's responsibility.
1038          *
1039          * @param $reason String
1040          * @param $suppress Boolean: hide content from sysops?
1041          * @return true on success, false on some kind of failure
1042          * STUB
1043          * Overridden by LocalFile
1044          */
1045         function delete( $reason, $suppress = false ) {
1046                 $this->readOnlyError();
1047         }
1048
1049         /**
1050          * Restore all or specified deleted revisions to the given file.
1051          * Permissions and logging are left to the caller.
1052          *
1053          * May throw database exceptions on error.
1054          *
1055          * @param $versions set of record ids of deleted items to restore,
1056          *                    or empty to restore all revisions.
1057          * @param $unsuppress remove restrictions on content upon restoration?
1058          * @return the number of file revisions restored if successful,
1059          *         or false on failure
1060          * STUB
1061          * Overridden by LocalFile
1062          */
1063         function restore( $versions=array(), $unsuppress=false ) {
1064                 $this->readOnlyError();
1065         }
1066
1067         /**
1068          * Returns 'true' if this file is a type which supports multiple pages,
1069          * e.g. DJVU or PDF. Note that this may be true even if the file in
1070          * question only has a single page.
1071          *
1072          * @return Bool
1073          */
1074         function isMultipage() {
1075                 return $this->getHandler() && $this->handler->isMultiPage( $this );
1076         }
1077
1078         /**
1079          * Returns the number of pages of a multipage document, or false for
1080          * documents which aren't multipage documents
1081          */
1082         function pageCount() {
1083                 if ( !isset( $this->pageCount ) ) {
1084                         if ( $this->getHandler() && $this->handler->isMultiPage( $this ) ) {
1085                                 $this->pageCount = $this->handler->pageCount( $this );
1086                         } else {
1087                                 $this->pageCount = false;
1088                         }
1089                 }
1090                 return $this->pageCount;
1091         }
1092
1093         /**
1094          * Calculate the height of a thumbnail using the source and destination width
1095          */
1096         static function scaleHeight( $srcWidth, $srcHeight, $dstWidth ) {
1097                 // Exact integer multiply followed by division
1098                 if ( $srcWidth == 0 ) {
1099                         return 0;
1100                 } else {
1101                         return round( $srcHeight * $dstWidth / $srcWidth );
1102                 }
1103         }
1104
1105         /**
1106          * Get an image size array like that returned by getImageSize(), or false if it
1107          * can't be determined.
1108          *
1109          * @param $fileName String: The filename
1110          * @return Array
1111          */
1112         function getImageSize( $fileName ) {
1113                 if ( !$this->getHandler() ) {
1114                         return false;
1115                 }
1116                 return $this->handler->getImageSize( $this, $fileName );
1117         }
1118
1119         /**
1120          * Get the URL of the image description page. May return false if it is
1121          * unknown or not applicable.
1122          */
1123         function getDescriptionUrl() {
1124                 return $this->repo->getDescriptionUrl( $this->getName() );
1125         }
1126
1127         /**
1128          * Get the HTML text of the description page, if available
1129          */
1130         function getDescriptionText() {
1131                 global $wgMemc, $wgLang;
1132                 if ( !$this->repo->fetchDescription ) {
1133                         return false;
1134                 }
1135                 $renderUrl = $this->repo->getDescriptionRenderUrl( $this->getName(), $wgLang->getCode() );
1136                 if ( $renderUrl ) {
1137                         if ( $this->repo->descriptionCacheExpiry > 0 ) {
1138                                 wfDebug("Attempting to get the description from cache...");
1139                                 $key = $this->repo->getLocalCacheKey( 'RemoteFileDescription', 'url', $wgLang->getCode(),
1140                                                                         $this->getName() );
1141                                 $obj = $wgMemc->get($key);
1142                                 if ($obj) {
1143                                         wfDebug("success!\n");
1144                                         return $obj;
1145                                 }
1146                                 wfDebug("miss\n");
1147                         }
1148                         wfDebug( "Fetching shared description from $renderUrl\n" );
1149                         $res = Http::get( $renderUrl );
1150                         if ( $res && $this->repo->descriptionCacheExpiry > 0 ) {
1151                                 $wgMemc->set( $key, $res, $this->repo->descriptionCacheExpiry );
1152                         }
1153                         return $res;
1154                 } else {
1155                         return false;
1156                 }
1157         }
1158
1159         /**
1160          * Get discription of file revision
1161          * STUB
1162          */
1163         function getDescription() {
1164                 return null;
1165         }
1166
1167         /**
1168          * Get the 14-character timestamp of the file upload, or false if
1169          * it doesn't exist
1170          */
1171         function getTimestamp() {
1172                 $path = $this->getPath();
1173                 if ( !file_exists( $path ) ) {
1174                         return false;
1175                 }
1176                 return wfTimestamp( TS_MW, filemtime( $path ) );
1177         }
1178
1179         /**
1180          * Get the SHA-1 base 36 hash of the file
1181          */
1182         function getSha1() {
1183                 return self::sha1Base36( $this->getPath() );
1184         }
1185
1186         /**
1187          * Get the deletion archive key, <sha1>.<ext>
1188          */
1189         function getStorageKey() {
1190                 $hash = $this->getSha1();
1191                 if ( !$hash ) {
1192                         return false;
1193                 }
1194                 $ext = $this->getExtension();
1195                 $dotExt = $ext === '' ? '' : ".$ext";
1196                 return $hash . $dotExt;
1197         }
1198
1199         /**
1200          * Determine if the current user is allowed to view a particular
1201          * field of this file, if it's marked as deleted.
1202          * STUB
1203          * @param $field Integer
1204          * @return Boolean
1205          */
1206         function userCan( $field ) {
1207                 return true;
1208         }
1209
1210         /**
1211          * Get an associative array containing information about a file in the local filesystem.
1212          *
1213          * @param $path String: absolute local filesystem path
1214          * @param $ext Mixed: the file extension, or true to extract it from the filename.
1215          *             Set it to false to ignore the extension.
1216          */
1217         static function getPropsFromPath( $path, $ext = true ) {
1218                 wfProfileIn( __METHOD__ );
1219                 wfDebug( __METHOD__.": Getting file info for $path\n" );
1220                 $info = array(
1221                         'fileExists' => file_exists( $path ) && !is_dir( $path )
1222                 );
1223                 $gis = false;
1224                 if ( $info['fileExists'] ) {
1225                         $magic = MimeMagic::singleton();
1226
1227                         if ( $ext === true ) {
1228                                 $i = strrpos( $path, '.' );
1229                                 $ext = strtolower( $i ? substr( $path, $i + 1 ) : '' );
1230                         }
1231
1232                         # mime type according to file contents
1233                         $info['file-mime'] = $magic->guessMimeType( $path, false );
1234                         # logical mime type
1235                         $info['mime'] = $magic->improveTypeFromExtension( $info['file-mime'], $ext );
1236
1237                         list( $info['major_mime'], $info['minor_mime'] ) = self::splitMime( $info['mime'] );
1238                         $info['media_type'] = $magic->getMediaType( $path, $info['mime'] );
1239
1240                         # Get size in bytes
1241                         $info['size'] = filesize( $path );
1242
1243                         # Height, width and metadata
1244                         $handler = MediaHandler::getHandler( $info['mime'] );
1245                         if ( $handler ) {
1246                                 $tempImage = (object)array();
1247                                 $info['metadata'] = $handler->getMetadata( $tempImage, $path );
1248                                 $gis = $handler->getImageSize( $tempImage, $path, $info['metadata'] );
1249                         } else {
1250                                 $gis = false;
1251                                 $info['metadata'] = '';
1252                         }
1253                         $info['sha1'] = self::sha1Base36( $path );
1254
1255                         wfDebug(__METHOD__.": $path loaded, {$info['size']} bytes, {$info['mime']}.\n");
1256                 } else {
1257                         $info['mime'] = null;
1258                         $info['media_type'] = MEDIATYPE_UNKNOWN;
1259                         $info['metadata'] = '';
1260                         $info['sha1'] = '';
1261                         wfDebug(__METHOD__.": $path NOT FOUND!\n");
1262                 }
1263                 if( $gis ) {
1264                         # NOTE: $gis[2] contains a code for the image type. This is no longer used.
1265                         $info['width'] = $gis[0];
1266                         $info['height'] = $gis[1];
1267                         if ( isset( $gis['bits'] ) ) {
1268                                 $info['bits'] = $gis['bits'];
1269                         } else {
1270                                 $info['bits'] = 0;
1271                         }
1272                 } else {
1273                         $info['width'] = 0;
1274                         $info['height'] = 0;
1275                         $info['bits'] = 0;
1276                 }
1277                 wfProfileOut( __METHOD__ );
1278                 return $info;
1279         }
1280
1281         /**
1282          * Get a SHA-1 hash of a file in the local filesystem, in base-36 lower case
1283          * encoding, zero padded to 31 digits.
1284          *
1285          * 160 log 2 / log 36 = 30.95, so the 160-bit hash fills 31 digits in base 36
1286          * fairly neatly.
1287          *
1288          * Returns false on failure
1289          */
1290         static function sha1Base36( $path ) {
1291                 wfSuppressWarnings();
1292                 $hash = sha1_file( $path );
1293                 wfRestoreWarnings();
1294                 if ( $hash === false ) {
1295                         return false;
1296                 } else {
1297                         return wfBaseConvert( $hash, 16, 36, 31 );
1298                 }
1299         }
1300
1301         function getLongDesc() {
1302                 $handler = $this->getHandler();
1303                 if ( $handler ) {
1304                         return $handler->getLongDesc( $this );
1305                 } else {
1306                         return MediaHandler::getGeneralLongDesc( $this );
1307                 }
1308         }
1309
1310         function getShortDesc() {
1311                 $handler = $this->getHandler();
1312                 if ( $handler ) {
1313                         return $handler->getShortDesc( $this );
1314                 } else {
1315                         return MediaHandler::getGeneralShortDesc( $this );
1316                 }
1317         }
1318
1319         function getDimensionsString() {
1320                 $handler = $this->getHandler();
1321                 if ( $handler ) {
1322                         return $handler->getDimensionsString( $this );
1323                 } else {
1324                         return '';
1325                 }
1326         }
1327
1328         function getRedirected() {
1329                 return $this->redirected;
1330         }
1331
1332         function getRedirectedTitle() {
1333                 if ( $this->redirected ) {
1334                         if ( !$this->redirectTitle )
1335                                 $this->redirectTitle = Title::makeTitle( NS_FILE, $this->redirected );
1336                         return $this->redirectTitle;
1337                 }
1338         }
1339
1340         function redirectedFrom( $from ) {
1341                 $this->redirected = $from;
1342         }
1343
1344         function isMissing() {
1345                 return false;
1346         }
1347 }
1348 /**
1349  * Aliases for backwards compatibility with 1.6
1350  */
1351 define( 'MW_IMG_DELETED_FILE', File::DELETED_FILE );
1352 define( 'MW_IMG_DELETED_COMMENT', File::DELETED_COMMENT );
1353 define( 'MW_IMG_DELETED_USER', File::DELETED_USER );
1354 define( 'MW_IMG_DELETED_RESTRICTED', File::DELETED_RESTRICTED );