Add HTMLPreloadScanner support for <link rel=preload>

third_party/WebKit/Source/core/html/parser/HTMLPreloadScanner.cpp

 /*
  * Copyright (C) 2008 Apple Inc. All Rights Reserved.
  * Copyright (C) 2009 Torch Mobile, Inc. http://www.torchmobile.com/
  * Copyright (C) 2010 Google Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 26 matching lines @@
 #include "core/fetch/IntegrityMetadata.h"
 #include "core/frame/Settings.h"
 #include "core/frame/SubresourceIntegrity.h"
 #include "core/html/CrossOriginAttribute.h"
 #include "core/html/HTMLImageElement.h"
 #include "core/html/HTMLMetaElement.h"
 #include "core/html/LinkRelAttribute.h"
 #include "core/html/parser/HTMLParserIdioms.h"
 #include "core/html/parser/HTMLSrcsetParser.h"
 #include "core/html/parser/HTMLTokenizer.h"
+#include "core/loader/LinkLoader.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/TraceEvent.h"
 #include "wtf/MainThread.h"
 
 namespace blink {
 
 using namespace HTMLNames;
 
 static bool match(const StringImpl* impl, const QualifiedName& qName)
 {
@@ skipping 52 matching lines @@
     return mediaQueryEvaluator.eval(mediaQueries.get());
 }
 
 class TokenPreloadScanner::StartTagScanner {
     STACK_ALLOCATED();
 public:
     StartTagScanner(const StringImpl* tagImpl, PassRefPtrWillBeRawPtr<MediaValues> mediaValues)
         : m_tagImpl(tagImpl)
         , m_linkIsStyleSheet(false)
         , m_linkIsPreconnect(false)
+        , m_linkIsPreload(false)
         , m_linkIsImport(false)
         , m_matchedMediaAttribute(true)
         , m_inputIsImage(false)
         , m_sourceSize(0)
         , m_sourceSizeSet(false)
         , m_defer(FetchRequest::NoDefer)
         , m_crossOrigin(CrossOriginAttributeNotSet)
         , m_mediaValues(mediaValues)
         , m_referrerPolicySet(false)
         , m_referrerPolicy(ReferrerPolicyDefault)
@@ skipping 46 matching lines @@
         } else if (match(m_tagImpl, imgTag) && !pictureData.sourceURL.isEmpty()) {
             setUrlToLoad(pictureData.sourceURL, AllowURLReplacement);
         }
     }
 
     PassOwnPtr<PreloadRequest> createPreloadRequest(const KURL& predictedBaseURL, const SegmentedString& source, const ClientHintsPreferences& clientHintsPreferences, const PictureData& pictureData, const ReferrerPolicy documentReferrerPolicy)
     {
         PreloadRequest::RequestType requestType = PreloadRequest::RequestTypePreload;
         if (shouldPreconnect())
             requestType = PreloadRequest::RequestTypePreconnect;
+        else if (isLinkRelPreload())
+            requestType = PreloadRequest::RequestTypeLinkRelPreload;
         else if (!shouldPreload() || !m_matchedMediaAttribute)
             return nullptr;
 
         TextPosition position = TextPosition(source.currentLine(), source.currentColumn());
         FetchRequest::ResourceWidth resourceWidth;
         float sourceSize = m_sourceSize;
         bool sourceSizeSet = m_sourceSizeSet;
         if (pictureData.picked) {
             sourceSizeSet = pictureData.sourceSizeSet;
             sourceSize = pictureData.sourceSize;
@@ skipping 58 matching lines @@
     template<typename NameType>
     void processLinkAttribute(const NameType& attributeName, const String& attributeValue)
     {
         // FIXME - Don't set rel/media/crossorigin multiple times.
         if (match(attributeName, hrefAttr)) {
             setUrlToLoad(attributeValue, DisallowURLReplacement);
         } else if (match(attributeName, relAttr)) {
             LinkRelAttribute rel(attributeValue);
             m_linkIsStyleSheet = rel.isStyleSheet() && !rel.isAlternate() && rel.iconType() == InvalidIcon && !rel.isDNSPrefetch();
             m_linkIsPreconnect = rel.isPreconnect();
+            m_linkIsPreload = rel.isLinkPreload();
             m_linkIsImport = rel.isImport();
         } else if (match(attributeName, mediaAttr)) {
             m_matchedMediaAttribute = mediaAttributeMatches(*m_mediaValues, attributeValue);
         } else if (match(attributeName, crossoriginAttr)) {
             setCrossOrigin(attributeValue);
+        } else if (match(attributeName, asAttr)) {
+            m_asAttributeValue = attributeValue;
         }
     }
 
     template<typename NameType>
     void processInputAttribute(const NameType& attributeName, const String& attributeValue)
     {
         // FIXME - Don't set type multiple times.
         if (match(attributeName, srcAttr))
             setUrlToLoad(attributeValue, DisallowURLReplacement);
         else if (match(attributeName, typeAttr))
@@ skipping 68 matching lines @@
     Resource::Type resourceType() const
     {
         if (match(m_tagImpl, scriptTag))
             return Resource::Script;
         if (match(m_tagImpl, imgTag) || match(m_tagImpl, videoTag) || (match(m_tagImpl, inputTag) && m_inputIsImage))
             return Resource::Image;
         if (match(m_tagImpl, linkTag) && m_linkIsStyleSheet)
             return Resource::CSSStyleSheet;
         if (m_linkIsPreconnect)
             return Resource::Raw;
+        if (m_linkIsPreload)
+            return LinkLoader::getTypeFromAsAttribute(m_asAttributeValue, nullptr);
         if (match(m_tagImpl, linkTag) && m_linkIsImport)
             return Resource::ImportResource;
         ASSERT_NOT_REACHED();
         return Resource::Raw;
     }
 
     bool shouldPreconnect() const
     {
         return match(m_tagImpl, linkTag) && m_linkIsPreconnect && !m_urlToLoad.isEmpty();
     }
 
+    bool isLinkRelPreload() const
+    {
+        return match(m_tagImpl, linkTag) && m_linkIsPreload && !m_urlToLoad.isEmpty();
+    }
+
     bool shouldPreload() const
     {
         if (m_urlToLoad.isEmpty())
             return false;
-        if (match(m_tagImpl, linkTag) && !m_linkIsStyleSheet && !m_linkIsImport)
+        if (match(m_tagImpl, linkTag) && !m_linkIsStyleSheet && !m_linkIsImport && !m_linkIsPreload)
             return false;
         if (match(m_tagImpl, inputTag) && !m_inputIsImage)
             return false;
         return true;
     }
     void setCrossOrigin(const String& corsSetting)
     {
         m_crossOrigin = crossOriginAttributeValue(corsSetting);
     }
 
     void setDefer(FetchRequest::DeferOption defer)
     {
         m_defer = defer;
 
     }
 
     bool defer() const
     {
         return m_defer;
     }
 
     const StringImpl* m_tagImpl;
     String m_urlToLoad;
     ImageCandidate m_srcsetImageCandidate;
     String m_charset;
     bool m_linkIsStyleSheet;
     bool m_linkIsPreconnect;
+    bool m_linkIsPreload;
     bool m_linkIsImport;
     bool m_matchedMediaAttribute;
     bool m_inputIsImage;
     String m_imgSrcUrl;
     String m_srcsetAttributeValue;
+    String m_asAttributeValue;
     float m_sourceSize;
     bool m_sourceSizeSet;
     FetchRequest::DeferOption m_defer;
     CrossOriginAttributeValue m_crossOrigin;
     RefPtrWillBeMember<MediaValues> m_mediaValues;
     bool m_referrerPolicySet;
     ReferrerPolicy m_referrerPolicy;
     IntegrityMetadataSet m_integrityMetadata;
 };
 
@@ skipping 245 matching lines @@
     else
         mediaValues = MediaValuesCached::create(*document);
     ASSERT(mediaValues->isSafeToSendToAnotherThread());
     defaultViewportMinWidth = document->viewportDefaultMinWidth();
     viewportMetaZeroValuesQuirk = document->settings() && document->settings()->viewportMetaZeroValuesQuirk();
     viewportMetaEnabled = document->settings() && document->settings()->viewportMetaEnabled();
     referrerPolicy = ReferrerPolicyDefault;
 }
 
 }