Threaded data provider: Support main thread data notifications (Blink side)

Source/core/html/parser/HTMLDocumentParser.cpp

Index: Source/core/html/parser/HTMLDocumentParser.cpp
diff --git a/Source/core/html/parser/HTMLDocumentParser.cpp b/Source/core/html/parser/HTMLDocumentParser.cpp
index 5e89dc7c97a5cbb5cd0efdcf1bac319f77b55eb2..f2d863d4adb9bcd08937d37e84eaa7c5a68a3a1e 100644
--- a/Source/core/html/parser/HTMLDocumentParser.cpp
+++ b/Source/core/html/parser/HTMLDocumentParser.cpp
@@ -75,10 +75,11 @@ static HTMLTokenizer::State tokenizerStateForContextElement(Element* contextElem
     return HTMLTokenizer::DataState;
 }
 
-class ParserDataReceiver : public blink::WebThreadedDataReceiver {
+class ParserDataReceiver : public WebThreadedDataReceiver {
 public:
-    explicit ParserDataReceiver(WeakPtr<BackgroundHTMLParser> backgroundParser)
+    explicit ParserDataReceiver(WeakPtr<BackgroundHTMLParser> backgroundParser, WeakPtrWillBeRawPtr<Document> document)
         : m_backgroundParser(backgroundParser)
+        , m_document(document)
     {
     }
 
@@ -98,8 +99,17 @@ public:
         return nullptr;
     }
 
+    virtual bool needsMainthreadDataCopy() override final { return InspectorInstrumentation::hasFrontends(); }
+    virtual void acceptMainthreadDataNotification(const char* data, int dataLength, int encodedDataLength) override final
+    {

[kouhei (in TOK), 2014/11/18 04:49:55]

please add ASSERT(isMainThread());

+        ASSERT(!data || m_needMainthreadDataCopy);
+        if (m_document.get())
+            m_document.get()->loader()->acceptDataFromThreadedReceiver(data, dataLength, encodedDataLength);
+    }
+
 private:
     WeakPtr<BackgroundHTMLParser> m_backgroundParser;
+    WeakPtrWillBeRawPtr<Document> m_document;

[kouhei (in TOK), 2014/11/18 04:49:55]

This would not work on Oilpan, as RawPtr is not nuked when Document is
destructed.
I'm not sure how to solve this though...

haraken: Do you have any ideas?

[haraken, 2014/11/18 04:57:27]

Can't this simply be a RefPtr?

In the first place, I don't understand why Document::contextDocument() returns a
WeakPtrWillBeRawPtr. It's error-prone to pass WeakPtr around, so I think
Document::contextDocument() should just return a Document*. It looks like almost
all call sites of Document::contextDocument() are interested in a Document*
pointer, not WeakPtr<Document>.

 };
 
 HTMLDocumentParser::HTMLDocumentParser(HTMLDocument& document, bool reportErrors)
@@ -722,7 +732,7 @@ void HTMLDocumentParser::startBackgroundParser()
     // TODO(oysteine): Disabled due to crbug.com/398076 until a full fix can be implemented.
     if (RuntimeEnabledFeatures::threadedParserDataReceiverEnabled()) {

[kouhei (in TOK), 2014/11/18 04:49:55]

I think this is still marked as experimental and not enabled by default.

[oystein (OOO til 10th of July), 2014/11/20 23:24:57]

Yes, I put it behind the flag when we discovered this bug. It should be the only
blocker for the feature.

         if (DocumentLoader* loader = document()->loader())
-            loader->attachThreadedDataReceiver(adoptPtr(new ParserDataReceiver(m_backgroundParser)));
+            loader->attachThreadedDataReceiver(adoptPtr(new ParserDataReceiver(m_backgroundParser, document()->contextDocument())));
     }
 
     OwnPtr<BackgroundHTMLParser::Configuration> config = adoptPtr(new BackgroundHTMLParser::Configuration);