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                 $status = $this->rasterize( $srcPath, $dstPath, $physicalWidth, $physicalHeight, $lang );
 189                 if ( $status === true ) {
 190                         return new ThumbnailImage( $image, $dstUrl, $dstPath, $params );
 191                 } else {
 192                         return $status; // MediaTransformError
 193                 }
 194         }
 195
 196         /**
 197          * Transform an SVG file to PNG
 198          * This function can be called outside of thumbnail contexts
 199          * @param string $srcPath
 200          * @param string $dstPath
 201          * @param string $width
 202          * @param string $height
 203          * @param bool|string $lang Language code of the language to render the SVG in
 204          * @throws MWException
 205          * @return bool|MediaTransformError
 206          */
 207         public function rasterize( $srcPath, $dstPath, $width, $height, $lang = false ) {
 208                 global $wgSVGConverters, $wgSVGConverter, $wgSVGConverterPath;
 209                 $err = false;
 210                 $retval = '';
 211                 if ( isset( $wgSVGConverters[$wgSVGConverter] ) ) {
 212                         if ( is_array( $wgSVGConverters[$wgSVGConverter] ) ) {
 213                                 // This is a PHP callable
 214                                 $func = $wgSVGConverters[$wgSVGConverter][0];
 215                                 $args = array_merge( array( $srcPath, $dstPath, $width, $height, $lang ),
 216                                         array_slice( $wgSVGConverters[$wgSVGConverter], 1 ) );
 217                                 if ( !is_callable( $func ) ) {
 218                                         throw new MWException( "$func is not callable" );
 219                                 }
 220                                 $err = call_user_func_array( $func, $args );
 221                                 $retval = (bool)$err;
 222                         } else {
 223                                 // External command
 224                                 $cmd = str_replace(
 225                                         array( '$path/', '$width', '$height', '$input', '$output' ),
 226                                         array( $wgSVGConverterPath ? wfEscapeShellArg( "$wgSVGConverterPath/" ) : "",
 227                                                 intval( $width ),
 228                                                 intval( $height ),
 229                                                 wfEscapeShellArg( $srcPath ),
 230                                                 wfEscapeShellArg( $dstPath ) ),
 231                                         $wgSVGConverters[$wgSVGConverter]
 232                                 );
 233
 234                                 $env = array();
 235                                 if ( $lang !== false ) {
 236                                         $env['LANG'] = $lang;
 237                                 }
 238
 239                                 wfProfileIn( 'rsvg' );
 240                                 wfDebug( __METHOD__ . ": $cmd\n" );
 241                                 $err = wfShellExecWithStderr( $cmd, $retval, $env );
 242                                 wfProfileOut( 'rsvg' );
 243                         }
 244                 }
 245                 $removed = $this->removeBadFile( $dstPath, $retval );
 246                 if ( $retval != 0 || $removed ) {
 247                         $this->logErrorForExternalProcess( $retval, $err, $cmd );
 248                         return new MediaTransformError( 'thumbnail_error', $width, $height, $err );
 249                 }
 250
 251                 return true;
 252         }
 253
 254         public static function rasterizeImagickExt( $srcPath, $dstPath, $width, $height ) {
 255                 $im = new Imagick( $srcPath );
 256                 $im->setImageFormat( 'png' );
 257                 $im->setBackgroundColor( 'transparent' );
 258                 $im->setImageDepth( 8 );
 259
 260                 if ( !$im->thumbnailImage( intval( $width ), intval( $height ), /* fit */ false ) ) {
 261                         return 'Could not resize image';
 262                 }
 263                 if ( !$im->writeImage( $dstPath ) ) {
 264                         return "Could not write to $dstPath";
 265                 }
 266         }
 267
 268         /**
 269          * @param File $file
 270          * @param string $path Unused
 271          * @param bool|array $metadata
 272          * @return array
 273          */
 274         function getImageSize( $file, $path, $metadata = false ) {
 275                 if ( $metadata === false ) {
 276                         $metadata = $file->getMetaData();
 277                 }
 278                 $metadata = $this->unpackMetaData( $metadata );
 279
 280                 if ( isset( $metadata['width'] ) && isset( $metadata['height'] ) ) {
 281                         return array( $metadata['width'], $metadata['height'], 'SVG',
 282                                 "width=\"{$metadata['width']}\" height=\"{$metadata['height']}\"" );
 283                 } else { // error
 284                         return array( 0, 0, 'SVG', "width=\"0\" height=\"0\"" );
 285                 }
 286         }
 287
 288         function getThumbType( $ext, $mime, $params = null ) {
 289                 return array( 'png', 'image/png' );
 290         }
 291
 292         /**
 293          * Subtitle for the image. Different from the base
 294          * class so it can be denoted that SVG's have
 295          * a "nominal" resolution, and not a fixed one,
 296          * as well as so animation can be denoted.
 297          *
 298          * @param File $file
 299          * @return string
 300          */
 301         function getLongDesc( $file ) {
 302                 global $wgLang;
 303
 304                 $metadata = $this->unpackMetadata( $file->getMetadata() );
 305                 if ( isset( $metadata['error'] ) ) {
 306                         return wfMessage( 'svg-long-error', $metadata['error']['message'] )->text();
 307                 }
 308
 309                 $size = $wgLang->formatSize( $file->getSize() );
 310
 311                 if ( $this->isAnimatedImage( $file ) ) {
 312                         $msg = wfMessage( 'svg-long-desc-animated' );
 313                 } else {
 314                         $msg = wfMessage( 'svg-long-desc' );
 315                 }
 316
 317                 $msg->numParams( $file->getWidth(), $file->getHeight() )->params( $size );
 318
 319                 return $msg->parse();
 320         }
 321
 322         /**
 323          * @param File $file
 324          * @param string $filename
 325          * @return string Serialised metadata
 326          */
 327         function getMetadata( $file, $filename ) {
 328                 $metadata = array( 'version' => self::SVG_METADATA_VERSION );
 329                 try {
 330                         $metadata += SVGMetadataExtractor::getMetadata( $filename );
 331                 } catch ( MWException $e ) { // @todo SVG specific exceptions
 332                         // File not found, broken, etc.
 333                         $metadata['error'] = array(
 334                                 'message' => $e->getMessage(),
 335                                 'code' => $e->getCode()
 336                         );
 337                         wfDebug( __METHOD__ . ': ' . $e->getMessage() . "\n" );
 338                 }
 339
 340                 return serialize( $metadata );
 341         }
 342
 343         function unpackMetadata( $metadata ) {
 344                 wfSuppressWarnings();
 345                 $unser = unserialize( $metadata );
 346                 wfRestoreWarnings();
 347                 if ( isset( $unser['version'] ) && $unser['version'] == self::SVG_METADATA_VERSION ) {
 348                         return $unser;
 349                 } else {
 350                         return false;
 351                 }
 352         }
 353
 354         function getMetadataType( $image ) {
 355                 return 'parsed-svg';
 356         }
 357
 358         function isMetadataValid( $image, $metadata ) {
 359                 $meta = $this->unpackMetadata( $metadata );
 360                 if ( $meta === false ) {
 361                         return self::METADATA_BAD;
 362                 }
 363                 if ( !isset( $meta['originalWidth'] ) ) {
 364                         // Old but compatible
 365                         return self::METADATA_COMPATIBLE;
 366                 }
 367
 368                 return self::METADATA_GOOD;
 369         }
 370
 371         protected function visibleMetadataFields() {
 372                 $fields = array( 'objectname', 'imagedescription' );
 373
 374                 return $fields;
 375         }
 376
 377         /**
 378          * @param File $file
 379          * @return array|bool
 380          */
 381         function formatMetadata( $file ) {
 382                 $result = array(
 383                         'visible' => array(),
 384                         'collapsed' => array()
 385                 );
 386                 $metadata = $file->getMetadata();
 387                 if ( !$metadata ) {
 388                         return false;
 389                 }
 390                 $metadata = $this->unpackMetadata( $metadata );
 391                 if ( !$metadata || isset( $metadata['error'] ) ) {
 392                         return false;
 393                 }
 394
 395                 /* @todo Add a formatter
 396                 $format = new FormatSVG( $metadata );
 397                 $formatted = $format->getFormattedData();
 398                 */
 399
 400                 // Sort fields into visible and collapsed
 401                 $visibleFields = $this->visibleMetadataFields();
 402
 403                 $showMeta = false;
 404                 foreach ( $metadata as $name => $value ) {
 405                         $tag = strtolower( $name );
 406                         if ( isset( self::$metaConversion[$tag] ) ) {
 407                                 $tag = strtolower( self::$metaConversion[$tag] );
 408                         } else {
 409                                 // Do not output other metadata not in list
 410                                 continue;
 411                         }
 412                         $showMeta = true;
 413                         self::addMeta( $result,
 414                                 in_array( $tag, $visibleFields ) ? 'visible' : 'collapsed',
 415                                 'exif',
 416                                 $tag,
 417                                 $value
 418                         );
 419                 }
 420
 421                 return $showMeta ? $result : false;
 422         }
 423
 424         /**
 425          * @param string $name Parameter name
 426          * @param mixed $value Parameter value
 427          * @return bool Validity
 428          */
 429         function validateParam( $name, $value ) {
 430                 if ( in_array( $name, array( 'width', 'height' ) ) ) {
 431                         // Reject negative heights, widths
 432                         return ( $value > 0 );
 433                 } elseif ( $name == 'lang' ) {
 434                         // Validate $code
 435                         if ( $value === '' || !Language::isValidBuiltinCode( $value ) ) {
 436                                 wfDebug( "Invalid user language code\n" );
 437
 438                                 return false;
 439                         }
 440
 441                         return true;
 442                 }
 443
 444                 // Only lang, width and height are acceptable keys
 445                 return false;
 446         }
 447
 448         /**
 449          * @param array $params name=>value pairs of parameters
 450          * @return string Filename to use
 451          */
 452         function makeParamString( $params ) {
 453                 $lang = '';
 454                 if ( isset( $params['lang'] ) && $params['lang'] !== 'en' ) {
 455                         $params['lang'] = mb_strtolower( $params['lang'] );
 456                         $lang = "lang{$params['lang']}-";
 457                 }
 458                 if ( !isset( $params['width'] ) ) {
 459                         return false;
 460                 }
 461
 462                 return "$lang{$params['width']}px";
 463         }
 464
 465         function parseParamString( $str ) {
 466                 $m = false;
 467                 if ( preg_match( '/^lang([a-z]+(?:-[a-z]+)*)-(\d+)px$/', $str, $m ) ) {
 468                         return array( 'width' => array_pop( $m ), 'lang' => $m[1] );
 469                 } elseif ( preg_match( '/^(\d+)px$/', $str, $m ) ) {
 470                         return array( 'width' => $m[1], 'lang' => 'en' );
 471                 } else {
 472                         return false;
 473                 }
 474         }
 475
 476         function getParamMap() {
 477                 return array( 'img_lang' => 'lang', 'img_width' => 'width' );
 478         }
 479
 480         /**
 481          * @param array $params
 482          * @return array
 483          */
 484         function getScriptParams( $params ) {
 485                 $scriptParams = array( 'width' => $params['width'] );
 486                 if ( isset( $params['lang'] ) ) {
 487                         $scriptParams['lang'] = $params['lang'];
 488                 }
 489
 490                 return $scriptParams;
 491         }
 492
 493         public function getCommonMetaArray( File $file ) {
 494                 $metadata = $file->getMetadata();
 495                 if ( !$metadata ) {
 496                         return array();
 497                 }
 498                 $metadata = $this->unpackMetadata( $metadata );
 499                 if ( !$metadata || isset( $metadata['error'] ) ) {
 500                         return array();
 501                 }
 502                 $stdMetadata = array();
 503                 foreach ( $metadata as $name => $value ) {
 504                         $tag = strtolower( $name );
 505                         if ( $tag === 'originalwidth' || $tag === 'originalheight' ) {
 506                                 // Skip these. In the exif metadata stuff, it is assumed these
 507                                 // are measured in px, which is not the case here.
 508                                 continue;
 509                         }
 510                         if ( isset( self::$metaConversion[$tag] ) ) {
 511                                 $tag = self::$metaConversion[$tag];
 512                                 $stdMetadata[$tag] = $value;
 513                         }
 514                 }
 515
 516                 return $stdMetadata;
 517         }
 518 }