(bug 27508) SVGMetadataExtractor takes too much resources on huge svg's. Change it...

[lhc/web/wiklou.git] / includes / media / SVGMetadataExtractor.php

diff --git a/includes/media/SVGMetadataExtractor.php b/includes/media/SVGMetadataExtractor.php
index 967d671..b5c8df1 100644 (file)
--- a/includes/media/SVGMetadataExtractor.php
+++ b/includes/media/SVGMetadataExtractor.php
@@ -47,13 +47,40 @@ class SVGReader {
         * @param $source String: URI from which to read
         */
        function __construct( $source ) {
+               global $wgSVGMetadataCutoff;
                $this->reader = new XMLReader();
-               $this->reader->open( $source, null, LIBXML_NOERROR | LIBXML_NOWARNING );
+
+               // Don't use $file->getSize() since file object passed to SVGHandler::getMetadata is bogus.
+               $size = filesize( $source );
+               if ( $size === false ) {
+                       throw new MWException( "Error getting filesize of SVG." );
+               } 
+
+               if ( $size > $wgSVGMetadataCutoff ) {
+                       $this->debug( "SVG is $size bytes, which is bigger than $wgSVGMetadataCutoff. Truncating." );
+                       $contents = file_get_contents( $source, false, null, -1, $wgSVGMetadataCutoff );
+                       if ($contents === false) {
+                               throw new MWException( 'Error reading SVG file.' );
+                       }
+                       $this->reader->XML( $contents, null, LIBXML_NOERROR | LIBXML_NOWARNING );
+               } else {
+                       $this->reader->open( $source, null, LIBXML_NOERROR | LIBXML_NOWARNING );
+               }
 
                $this->metadata['width'] = self::DEFAULT_WIDTH;
                $this->metadata['height'] = self::DEFAULT_HEIGHT;
 
-               $this->read();
+               // Because we cut off the end of the svg making an invalid one. Complicated
+               // try catch thing to make sure warnings get restored. Seems like there should
+               // be a better way.
+               wfSuppressWarnings();
+               try {
+                       $this->read();
+               } catch( Exception $e ) {
+                       wfRestoreWarnings();
+                       throw $e;
+               }
+               wfRestoreWarnings();
        }
 
        /*
@@ -83,7 +110,6 @@ class SVGReader {
 
                $exitDepth =  $this->reader->depth;
                $keepReading = $this->reader->read();
-               $skip = false;
                while ( $keepReading ) {
                        $tag = $this->reader->name;
                        $type = $this->reader->nodeType;
@@ -100,17 +126,15 @@ class SVGReader {
                                $this->readXml( $tag, 'metadata' );
                        } elseif ( $tag !== '#text' ) {
                                $this->debug( "Unhandled top-level XML tag $tag" );
-                               $this->animateFilter( $tag );
-                               //$skip = true;
-                       }
 
-                       if ($skip) {
-                               $keepReading = $this->reader->next();
-                               $skip = false;
-                               $this->debug( "Skip" );
-                       } else {
-                               $keepReading = $this->reader->read();
+                               if ( !isset( $this->metadata['animated'] ) ) {
+                                       // Recurse into children of current tag, looking for animation.
+                                       $this->animateFilter( $tag );
+                               }
                        }
+
+                       // Goto next element, which is sibling of current (Skip children).
+                       $keepReading = $this->reader->next();
                }
 
                $this->reader->close();
@@ -134,7 +158,7 @@ class SVGReader {
                        if( $this->reader->name == $name && $this->reader->nodeType == XmlReader::END_ELEMENT ) {
                                break;
                        } elseif( $this->reader->nodeType == XmlReader::TEXT ){
-                               $this->metadata[$metafield] = $this->reader->value;
+                               $this->metadata[$metafield] = trim( $this->reader->value );
                        }
                        $keepReading = $this->reader->read();
                }