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