includes/filerepo/File.php

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