includes/media/SVG.php

   1 <?php
   2 /**
   3  * Handler for SVG images.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  18  * http://www.gnu.org/copyleft/gpl.html
  19  *
  20  * @file
  21  * @ingroup Media
  22  */
  23 use Wikimedia\ScopedCallback;
  24
  25 /**
  26  * Handler for SVG images.
  27  *
  28  * @ingroup Media
  29  */
  30 class SvgHandler extends ImageHandler {
  31         const SVG_METADATA_VERSION = 2;
  32
  33         /** @var array A list of metadata tags that can be converted
  34          *  to the commonly used exif tags. This allows messages
  35          *  to be reused, and consistent tag names for {{#formatmetadata:..}}
  36          */
  37         private static $metaConversion = [
  38                 'originalwidth' => 'ImageWidth',
  39                 'originalheight' => 'ImageLength',
  40                 'description' => 'ImageDescription',
  41                 'title' => 'ObjectName',
  42         ];
  43
  44         function isEnabled() {
  45                 global $wgSVGConverters, $wgSVGConverter;
  46                 if ( !isset( $wgSVGConverters[$wgSVGConverter] ) ) {
  47                         wfDebug( "\$wgSVGConverter is invalid, disabling SVG rendering.\n" );
  48
  49                         return false;
  50                 } else {
  51                         return true;
  52                 }
  53         }
  54
  55         public function mustRender( $file ) {
  56                 return true;
  57         }
  58
  59         function isVectorized( $file ) {
  60                 return true;
  61         }
  62
  63         /**
  64          * @param File $file
  65          * @return bool
  66          */
  67         function isAnimatedImage( $file ) {
  68                 # @todo Detect animated SVGs
  69                 $metadata = $file->getMetadata();
  70                 if ( $metadata ) {
  71                         $metadata = $this->unpackMetadata( $metadata );
  72                         if ( isset( $metadata['animated'] ) ) {
  73                                 return $metadata['animated'];
  74                         }
  75                 }
  76
  77                 return false;
  78         }
  79
  80         /**
  81          * Which languages (systemLanguage attribute) is supported.
  82          *
  83          * @note This list is not guaranteed to be exhaustive.
  84          * To avoid OOM errors, we only look at first bit of a file.
  85          * Thus all languages on this list are present in the file,
  86          * but its possible for the file to have a language not on
  87          * this list.
  88          *
  89          * @param File $file
  90          * @return array Array of language codes, or empty if no language switching supported.
  91          */
  92         public function getAvailableLanguages( File $file ) {
  93                 $metadata = $file->getMetadata();
  94                 $langList = [];
  95                 if ( $metadata ) {
  96                         $metadata = $this->unpackMetadata( $metadata );
  97                         if ( isset( $metadata['translations'] ) ) {
  98                                 foreach ( $metadata['translations'] as $lang => $langType ) {
  99                                         if ( $langType === SVGReader::LANG_FULL_MATCH ) {
 100                                                 $langList[] = $lang;
 101                                         }
 102                                 }
 103                         }
 104                 }
 105                 return $langList;
 106         }
 107
 108         /**
 109          * What language to render file in if none selected.
 110          *
 111          * @param File $file
 112          * @return string Language code.
 113          */
 114         public function getDefaultRenderLanguage( File $file ) {
 115                 return 'en';
 116         }
 117
 118         /**
 119          * We do not support making animated svg thumbnails
 120          * @param File $file
 121          * @return bool
 122          */
 123         function canAnimateThumbnail( $file ) {
 124                 return false;
 125         }
 126
 127         /**
 128          * @param File $image
 129          * @param array &$params
 130          * @return bool
 131          */
 132         function normaliseParams( $image, &$params ) {
 133                 global $wgSVGMaxSize;
 134                 if ( !parent::normaliseParams( $image, $params ) ) {
 135                         return false;
 136                 }
 137                 # Don't make an image bigger than wgMaxSVGSize on the smaller side
 138                 if ( $params['physicalWidth'] <= $params['physicalHeight'] ) {
 139                         if ( $params['physicalWidth'] > $wgSVGMaxSize ) {
 140                                 $srcWidth = $image->getWidth( $params['page'] );
 141                                 $srcHeight = $image->getHeight( $params['page'] );
 142                                 $params['physicalWidth'] = $wgSVGMaxSize;
 143                                 $params['physicalHeight'] = File::scaleHeight( $srcWidth, $srcHeight, $wgSVGMaxSize );
 144                         }
 145                 } else {
 146                         if ( $params['physicalHeight'] > $wgSVGMaxSize ) {
 147                                 $srcWidth = $image->getWidth( $params['page'] );
 148                                 $srcHeight = $image->getHeight( $params['page'] );
 149                                 $params['physicalWidth'] = File::scaleHeight( $srcHeight, $srcWidth, $wgSVGMaxSize );
 150                                 $params['physicalHeight'] = $wgSVGMaxSize;
 151                         }
 152                 }
 153
 154                 return true;
 155         }
 156
 157         /**
 158          * @param File $image
 159          * @param string $dstPath
 160          * @param string $dstUrl
 161          * @param array $params
 162          * @param int $flags
 163          * @return bool|MediaTransformError|ThumbnailImage|TransformParameterError
 164          */
 165         function doTransform( $image, $dstPath, $dstUrl, $params, $flags = 0 ) {
 166                 if ( !$this->normaliseParams( $image, $params ) ) {
 167                         return new TransformParameterError( $params );
 168                 }
 169                 $clientWidth = $params['width'];
 170                 $clientHeight = $params['height'];
 171                 $physicalWidth = $params['physicalWidth'];
 172                 $physicalHeight = $params['physicalHeight'];
 173                 $lang = isset( $params['lang'] ) ? $params['lang'] : $this->getDefaultRenderLanguage( $image );
 174
 175                 if ( $flags & self::TRANSFORM_LATER ) {
 176                         return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
 177                 }
 178
 179                 $metadata = $this->unpackMetadata( $image->getMetadata() );
 180                 if ( isset( $metadata['error'] ) ) { // sanity check
 181                         $err = wfMessage( 'svg-long-error', $metadata['error']['message'] );
 182
 183                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight, $err );
 184                 }
 185
 186                 if ( !wfMkdirParents( dirname( $dstPath ), null, __METHOD__ ) ) {
 187                         return new MediaTransformError( 'thumbnail_error', $clientWidth, $clientHeight,
 188                                 wfMessage( 'thumbnail_dest_directory' ) );
 189                 }
 190
 191                 $srcPath = $image->getLocalRefPath();
 192                 if ( $srcPath === false ) { // Failed to get local copy
 193                         wfDebugLog( 'thumbnail',
 194                                 sprintf( 'Thumbnail failed on %s: could not get local copy of "%s"',
 195                                         wfHostname(), $image->getName() ) );
 196
 197                         return new MediaTransformError( 'thumbnail_error',
 198                                 $params['width'], $params['height'],
 199                                 wfMessage( 'filemissing' )
 200                         );
 201                 }
 202
 203                 // Make a temp dir with a symlink to the local copy in it.
 204                 // This plays well with rsvg-convert policy for external entities.
 205                 // https://git.gnome.org/browse/librsvg/commit/?id=f01aded72c38f0e18bc7ff67dee800e380251c8e
 206                 $tmpDir = wfTempDir() . '/svg_' . wfRandomString( 24 );
 207                 $lnPath = "$tmpDir/" . basename( $srcPath );
 208                 $ok = mkdir( $tmpDir, 0771 );
 209                 if ( !$ok ) {
 210                         wfDebugLog( 'thumbnail',
 211                                 sprintf( 'Thumbnail failed on %s: could not create temporary directory %s',
 212                                         wfHostname(), $tmpDir ) );
 213                         return new MediaTransformError( 'thumbnail_error',
 214                                 $params['width'], $params['height'],
 215                                 wfMessage( 'thumbnail-temp-create' )->text()
 216                         );
 217                 }
 218                 $ok = symlink( $srcPath, $lnPath );
 219                 /** @noinspection PhpUnusedLocalVariableInspection */
 220                 $cleaner = new ScopedCallback( function () use ( $tmpDir, $lnPath ) {
 221                         MediaWiki\suppressWarnings();
 222                         unlink( $lnPath );
 223                         rmdir( $tmpDir );
 224                         MediaWiki\restoreWarnings();
 225                 } );
 226                 if ( !$ok ) {
 227                         wfDebugLog( 'thumbnail',
 228                                 sprintf( 'Thumbnail failed on %s: could not link %s to %s',
 229                                         wfHostname(), $lnPath, $srcPath ) );
 230                         return new MediaTransformError( 'thumbnail_error',
 231                                 $params['width'], $params['height'],
 232                                 wfMessage( 'thumbnail-temp-create' )
 233                         );
 234                 }
 235
 236                 $status = $this->rasterize( $lnPath, $dstPath, $physicalWidth, $physicalHeight, $lang );
 237                 if ( $status === true ) {
 238                         return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
 239                 } else {
 240                         return $status; // MediaTransformError
 241                 }
 242         }
 243
 244         /**
 245          * Transform an SVG file to PNG
 246          * This function can be called outside of thumbnail contexts
 247          * @param string $srcPath
 248          * @param string $dstPath
 249          * @param string $width
 250          * @param string $height
 251          * @param bool|string $lang Language code of the language to render the SVG in
 252          * @throws MWException
 253          * @return bool|MediaTransformError
 254          */
 255         public function rasterize( $srcPath, $dstPath, $width, $height, $lang = false ) {
 256                 global $wgSVGConverters, $wgSVGConverter, $wgSVGConverterPath;
 257                 $err = false;
 258                 $retval = '';
 259                 if ( isset( $wgSVGConverters[$wgSVGConverter] ) ) {
 260                         if ( is_array( $wgSVGConverters[$wgSVGConverter] ) ) {
 261                                 // This is a PHP callable
 262                                 $func = $wgSVGConverters[$wgSVGConverter][0];
 263                                 $args = array_merge( [ $srcPath, $dstPath, $width, $height, $lang ],
 264                                         array_slice( $wgSVGConverters[$wgSVGConverter], 1 ) );
 265                                 if ( !is_callable( $func ) ) {
 266                                         throw new MWException( "$func is not callable" );
 267                                 }
 268                                 $err = call_user_func_array( $func, $args );
 269                                 $retval = (bool)$err;
 270                         } else {
 271                                 // External command
 272                                 $cmd = str_replace(
 273                                         [ '$path/', '$width', '$height', '$input', '$output' ],
 274                                         [ $wgSVGConverterPath ? wfEscapeShellArg( "$wgSVGConverterPath/" ) : "",
 275                                                 intval( $width ),
 276                                                 intval( $height ),
 277                                                 wfEscapeShellArg( $srcPath ),
 278                                                 wfEscapeShellArg( $dstPath ) ],
 279                                         $wgSVGConverters[$wgSVGConverter]
 280                                 );
 281
 282                                 $env = [];
 283                                 if ( $lang !== false ) {
 284                                         $env['LANG'] = $lang;
 285                                 }
 286
 287                                 wfDebug( __METHOD__ . ": $cmd\n" );
 288                                 $err = wfShellExecWithStderr( $cmd, $retval, $env );
 289                         }
 290                 }
 291                 $removed = $this->removeBadFile( $dstPath, $retval );
 292                 if ( $retval != 0 || $removed ) {
 293                         $this->logErrorForExternalProcess( $retval, $err, $cmd );
 294                         return new MediaTransformError( 'thumbnail_error', $width, $height, $err );
 295                 }
 296
 297                 return true;
 298         }
 299
 300         public static function rasterizeImagickExt( $srcPath, $dstPath, $width, $height ) {
 301                 $im = new Imagick( $srcPath );
 302                 $im->setImageFormat( 'png' );
 303                 $im->setBackgroundColor( 'transparent' );
 304                 $im->setImageDepth( 8 );
 305
 306                 if ( !$im->thumbnailImage( intval( $width ), intval( $height ), /* fit */ false ) ) {
 307                         return 'Could not resize image';
 308                 }
 309                 if ( !$im->writeImage( $dstPath ) ) {
 310                         return "Could not write to $dstPath";
 311                 }
 312         }
 313
 314         /**
 315          * @param File|FSFile $file
 316          * @param string $path Unused
 317          * @param bool|array $metadata
 318          * @return array
 319          */
 320         function getImageSize( $file, $path, $metadata = false ) {
 321                 if ( $metadata === false && $file instanceof File ) {
 322                         $metadata = $file->getMetadata();
 323                 }
 324                 $metadata = $this->unpackMetadata( $metadata );
 325
 326                 if ( isset( $metadata['width'] ) && isset( $metadata['height'] ) ) {
 327                         return [ $metadata['width'], $metadata['height'], 'SVG',
 328                                 "width=\"{$metadata['width']}\" height=\"{$metadata['height']}\"" ];
 329                 } else { // error
 330                         return [ 0, 0, 'SVG', "width=\"0\" height=\"0\"" ];
 331                 }
 332         }
 333
 334         function getThumbType( $ext, $mime, $params = null ) {
 335                 return [ 'png', 'image/png' ];
 336         }
 337
 338         /**
 339          * Subtitle for the image. Different from the base
 340          * class so it can be denoted that SVG's have
 341          * a "nominal" resolution, and not a fixed one,
 342          * as well as so animation can be denoted.
 343          *
 344          * @param File $file
 345          * @return string
 346          */
 347         function getLongDesc( $file ) {
 348                 global $wgLang;
 349
 350                 $metadata = $this->unpackMetadata( $file->getMetadata() );
 351                 if ( isset( $metadata['error'] ) ) {
 352                         return wfMessage( 'svg-long-error', $metadata['error']['message'] )->text();
 353                 }
 354
 355                 $size = $wgLang->formatSize( $file->getSize() );
 356
 357                 if ( $this->isAnimatedImage( $file ) ) {
 358                         $msg = wfMessage( 'svg-long-desc-animated' );
 359                 } else {
 360                         $msg = wfMessage( 'svg-long-desc' );
 361                 }
 362
 363                 $msg->numParams( $file->getWidth(), $file->getHeight() )->params( $size );
 364
 365                 return $msg->parse();
 366         }
 367
 368         /**
 369          * @param File|FSFile $file
 370          * @param string $filename
 371          * @return string Serialised metadata
 372          */
 373         function getMetadata( $file, $filename ) {
 374                 $metadata = [ 'version' => self::SVG_METADATA_VERSION ];
 375                 try {
 376                         $metadata += SVGMetadataExtractor::getMetadata( $filename );
 377                 } catch ( Exception $e ) { // @todo SVG specific exceptions
 378                         // File not found, broken, etc.
 379                         $metadata['error'] = [
 380                                 'message' => $e->getMessage(),
 381                                 'code' => $e->getCode()
 382                         ];
 383                         wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
 384                 }
 385
 386                 return serialize( $metadata );
 387         }
 388
 389         function unpackMetadata( $metadata ) {
 390                 MediaWiki\suppressWarnings();
 391                 $unser = unserialize( $metadata );
 392                 MediaWiki\restoreWarnings();
 393                 if ( isset( $unser['version'] ) && $unser['version'] == self::SVG_METADATA_VERSION ) {
 394                         return $unser;
 395                 } else {
 396                         return false;
 397                 }
 398         }
 399
 400         function getMetadataType( $image ) {
 401                 return 'parsed-svg';
 402         }
 403
 404         function isMetadataValid( $image, $metadata ) {
 405                 $meta = $this->unpackMetadata( $metadata );
 406                 if ( $meta === false ) {
 407                         return self::METADATA_BAD;
 408                 }
 409                 if ( !isset( $meta['originalWidth'] ) ) {
 410                         // Old but compatible
 411                         return self::METADATA_COMPATIBLE;
 412                 }
 413
 414                 return self::METADATA_GOOD;
 415         }
 416
 417         protected function visibleMetadataFields() {
 418                 $fields = [ 'objectname', 'imagedescription' ];
 419
 420                 return $fields;
 421         }
 422
 423         /**
 424          * @param File $file
 425          * @param bool|IContextSource $context Context to use (optional)
 426          * @return array|bool
 427          */
 428         function formatMetadata( $file, $context = false ) {
 429                 $result = [
 430                         'visible' => [],
 431                         'collapsed' => []
 432                 ];
 433                 $metadata = $file->getMetadata();
 434                 if ( !$metadata ) {
 435                         return false;
 436                 }
 437                 $metadata = $this->unpackMetadata( $metadata );
 438                 if ( !$metadata || isset( $metadata['error'] ) ) {
 439                         return false;
 440                 }
 441
 442                 /* @todo Add a formatter
 443                 $format = new FormatSVG( $metadata );
 444                 $formatted = $format->getFormattedData();
 445                 */
 446
 447                 // Sort fields into visible and collapsed
 448                 $visibleFields = $this->visibleMetadataFields();
 449
 450                 $showMeta = false;
 451                 foreach ( $metadata as $name => $value ) {
 452                         $tag = strtolower( $name );
 453                         if ( isset( self::$metaConversion[$tag] ) ) {
 454                                 $tag = strtolower( self::$metaConversion[$tag] );
 455                         } else {
 456                                 // Do not output other metadata not in list
 457                                 continue;
 458                         }
 459                         $showMeta = true;
 460                         self::addMeta( $result,
 461                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 462                                 'exif',
 463                                 $tag,
 464                                 $value
 465                         );
 466                 }
 467
 468                 return $showMeta ? $result : false;
 469         }
 470
 471         /**
 472          * @param string $name Parameter name
 473          * @param mixed $value Parameter value
 474          * @return bool Validity
 475          */
 476         public function validateParam( $name, $value ) {
 477                 if ( in_array( $name, [ 'width', 'height' ] ) ) {
 478                         // Reject negative heights, widths
 479                         return ( $value > 0 );
 480                 } elseif ( $name == 'lang' ) {
 481                         // Validate $code
 482                         if ( $value === '' || !Language::isValidBuiltInCode( $value ) ) {
 483                                 wfDebug( "Invalid user language code\n" );
 484
 485                                 return false;
 486                         }
 487
 488                         return true;
 489                 }
 490
 491                 // Only lang, width and height are acceptable keys
 492                 return false;
 493         }
 494
 495         /**
 496          * @param array $params Name=>value pairs of parameters
 497          * @return string Filename to use
 498          */
 499         public function makeParamString( $params ) {
 500                 $lang = '';
 501                 if ( isset( $params['lang'] ) && $params['lang'] !== 'en' ) {
 502                         $params['lang'] = strtolower( $params['lang'] );
 503                         $lang = "lang{$params['lang']}-";
 504                 }
 505                 if ( !isset( $params['width'] ) ) {
 506                         return false;
 507                 }
 508
 509                 return "$lang{$params['width']}px";
 510         }
 511
 512         public function parseParamString( $str ) {
 513                 $m = false;
 514                 if ( preg_match( '/^lang([a-z]+(?:-[a-z]+)*)-(\d+)px$/', $str, $m ) ) {
 515                         return [ 'width' => array_pop( $m ), 'lang' => $m[1] ];
 516                 } elseif ( preg_match( '/^(\d+)px$/', $str, $m ) ) {
 517                         return [ 'width' => $m[1], 'lang' => 'en' ];
 518                 } else {
 519                         return false;
 520                 }
 521         }
 522
 523         public function getParamMap() {
 524                 return [ 'img_lang' => 'lang', 'img_width' => 'width' ];
 525         }
 526
 527         /**
 528          * @param array $params
 529          * @return array
 530          */
 531         function getScriptParams( $params ) {
 532                 $scriptParams = [ 'width' => $params['width'] ];
 533                 if ( isset( $params['lang'] ) ) {
 534                         $scriptParams['lang'] = $params['lang'];
 535                 }
 536
 537                 return $scriptParams;
 538         }
 539
 540         public function getCommonMetaArray( File $file ) {
 541                 $metadata = $file->getMetadata();
 542                 if ( !$metadata ) {
 543                         return [];
 544                 }
 545                 $metadata = $this->unpackMetadata( $metadata );
 546                 if ( !$metadata || isset( $metadata['error'] ) ) {
 547                         return [];
 548                 }
 549                 $stdMetadata = [];
 550                 foreach ( $metadata as $name => $value ) {
 551                         $tag = strtolower( $name );
 552                         if ( $tag === 'originalwidth' || $tag === 'originalheight' ) {
 553                                 // Skip these. In the exif metadata stuff, it is assumed these
 554                                 // are measured in px, which is not the case here.
 555                                 continue;
 556                         }
 557                         if ( isset( self::$metaConversion[$tag] ) ) {
 558                                 $tag = self::$metaConversion[$tag];
 559                                 $stdMetadata[$tag] = $value;
 560                         }
 561                 }
 562
 563                 return $stdMetadata;
 564         }
 565 }