Source/WebCore/loader/DocumentWriter.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2010. Adam Barth. All rights reserved.
  * Copyright (C) 2016 Apple 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.
  * 2.  Redistributions in binary form must reproduce the above copyright
  *     notice, this list of conditions and the following disclaimer in the
  *     documentation and/or other materials provided with the distribution.
  * 3.  Neither the name of Apple Inc. ("Apple") nor the names of
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "DocumentWriter.h"

 #include "ContentSecurityPolicy.h"
 #include "DOMImplementation.h"
 #include "DOMWindow.h"
 #include "DocumentInlines.h"
 #include "DocumentLoader.h"
 #include "Frame.h"
 #include "FrameLoader.h"
 #include "FrameLoaderClient.h"
 #include "FrameLoaderStateMachine.h"
 #include "FrameView.h"
 #include "MIMETypeRegistry.h"
 #include "PluginDocument.h"
 #include "RawDataDocumentParser.h"
 #include "ScriptController.h"
 #include "ScriptableDocumentParser.h"
 #include "SecurityOrigin.h"
 #include "SecurityOriginPolicy.h"
 #include "SecurityPolicy.h"
 #include "SegmentedString.h"
 #include "Settings.h"
 #include "SinkDocument.h"
 #include "TextResourceDecoder.h"
 #include <wtf/Ref.h>

 namespace WebCore {

 static inline bool canReferToParentFrameEncoding(const Frame* frame, const Frame* parentFrame)
 {
     if (is<XMLDocument>(frame->document()))
         return false;
     return parentFrame && parentFrame->document()->securityOrigin().isSameOriginDomain(frame->document()->securityOrigin());
 }

 // This is only called by ScriptController::executeIfJavaScriptURL
 // and always contains the result of evaluating a javascript: url.
 // This is the <iframe src="javascript:'html'"> case.
 void DocumentWriter::replaceDocumentWithResultOfExecutingJavascriptURL(const String& source, Document* ownerDocument)
 {
     m_frame->loader().stopAllLoaders();

     // If we are in the midst of changing the frame's document, don't execute script
     // that modifies the document further:
     if (m_frame->documentIsBeingReplaced())
         return;

     begin(m_frame->document()->url(), true, ownerDocument);

     setEncoding("UTF-8"_s, IsEncodingUserChosen::No);

     // begin() might fire an unload event, which will result in a situation where no new document has been attached,
     // and the old document has been detached. Therefore, bail out if no document is attached.
     if (!m_frame->document())
         return;

     if (!source.isNull()) {
         if (!m_hasReceivedSomeData) {
             m_hasReceivedSomeData = true;
             m_frame->document()->setCompatibilityMode(DocumentCompatibilityMode::NoQuirksMode);
         }

         if (DocumentParser* parser = m_frame->document()->parser()) {
             auto utf8Source = source.utf8();
             parser->appendBytes(*this, reinterpret_cast<const uint8_t*>(utf8Source.data()), utf8Source.length());
         }
     }

     end();
 }

 void DocumentWriter::clear()
 {
     m_decoder = nullptr;
     m_hasReceivedSomeData = false;
     if (!m_encodingWasChosenByUser)
         m_encoding = String();
 }

 bool DocumentWriter::begin()
 {
     return begin(URL());
 }

 Ref<Document> DocumentWriter::createDocument(const URL& url, ScriptExecutionContextIdentifier documentIdentifier)
 {
     if (!m_frame->loader().stateMachine().isDisplayingInitialEmptyDocument() && m_frame->loader().client().shouldAlwaysUsePluginDocument(m_mimeType))
         return PluginDocument::create(*m_frame, url);
 #if PLATFORM(IOS_FAMILY)
     if (MIMETypeRegistry::isPDFMIMEType(m_mimeType) && (m_frame->isMainFrame() || !m_frame->settings().useImageDocumentForSubframePDF()))
         return SinkDocument::create(*m_frame, url);
 #endif
     if (!m_frame->loader().client().hasHTMLView())
         return Document::createNonRenderedPlaceholder(*m_frame, url);
     return DOMImplementation::createDocument(m_mimeType, m_frame.get(), m_frame->settings(), url, documentIdentifier);
 }

 bool DocumentWriter::begin(const URL& urlReference, bool dispatch, Document* ownerDocument, ScriptExecutionContextIdentifier documentIdentifier)
 {
     // We grab a local copy of the URL because it's easy for callers to supply
     // a URL that will be deallocated during the execution of this function.
     // For example, see <https://bugs.webkit.org/show_bug.cgi?id=66360>.
     URL url = urlReference;

     // Create a new document before clearing the frame, because it may need to
     // inherit an aliased security context.
     Ref<Document> document = createDocument(url, documentIdentifier);

     // If the new document is for a Plugin but we're supposed to be sandboxed from Plugins,
     // then replace the document with one whose parser will ignore the incoming data (bug 39323)
     if (document->isPluginDocument() && document->isSandboxed(SandboxPlugins))
         document = SinkDocument::create(*m_frame, url);

     // FIXME: Do we need to consult the content security policy here about blocked plug-ins?

     bool shouldReuseDefaultView = m_frame->loader().stateMachine().isDisplayingInitialEmptyDocument()
         && m_frame->document()->isSecureTransitionTo(url)
         && (m_frame->window() && !m_frame->window()->wasWrappedWithoutInitializedSecurityOrigin() && m_frame->window()->mayReuseForNavigation());

     if (shouldReuseDefaultView) {
         ASSERT(m_frame->loader().documentLoader());
         if (auto* contentSecurityPolicy = m_frame->loader().documentLoader()->contentSecurityPolicy())
             shouldReuseDefaultView = !(contentSecurityPolicy->sandboxFlags() & SandboxOrigin);
     }

     // Temporarily extend the lifetime of the existing document so that FrameLoader::clear() doesn't destroy it as
     // we need to retain its ongoing set of upgraded requests in new navigation contexts per <http://www.w3.org/TR/upgrade-insecure-requests/>
     // and we may also need to inherit its Content Security Policy below.
     RefPtr<Document> existingDocument = m_frame->document();

     Function<void()> handleDOMWindowCreation = [this, document, shouldReuseDefaultView] {
         if (shouldReuseDefaultView)
             document->takeDOMWindowFrom(*m_frame->document());
         else
             document->createDOMWindow();
     };

     m_frame->loader().clear(document.ptr(), !shouldReuseDefaultView, !shouldReuseDefaultView, true, WTFMove(handleDOMWindowCreation));
     clear();

     // m_frame->loader().clear() might fire unload event which could remove the view of the document.
     // Bail out if document has no view.
     if (!document->view())
         return false;

     if (!shouldReuseDefaultView)
         m_frame->script().updatePlatformScriptObjects();

     m_frame->loader().setOutgoingReferrer(url);
     m_frame->setDocument(document.copyRef());

     if (m_decoder)
         document->setDecoder(m_decoder.get());
     if (ownerDocument) {
         // |document| is the result of evaluating a JavaScript URL.
         document->setCookieURL(ownerDocument->cookieURL());
         document->setSecurityOriginPolicy(ownerDocument->securityOriginPolicy());
         document->setStrictMixedContentMode(ownerDocument->isStrictMixedContentMode());
         document->setCrossOriginEmbedderPolicy(ownerDocument->crossOriginEmbedderPolicy());

         document->setContentSecurityPolicy(makeUnique<ContentSecurityPolicy>(URL { url }, document));
         document->contentSecurityPolicy()->copyStateFrom(ownerDocument->contentSecurityPolicy());
         document->contentSecurityPolicy()->setInsecureNavigationRequestsToUpgrade(ownerDocument->contentSecurityPolicy()->takeNavigationRequestsToUpgrade());
     } else if (existingDocument) {
         if (url.protocolIsData() || url.protocolIsBlob()) {
             document->setContentSecurityPolicy(makeUnique<ContentSecurityPolicy>(URL { url }, document));
             document->contentSecurityPolicy()->copyStateFrom(existingDocument->contentSecurityPolicy());
             document->setCrossOriginEmbedderPolicy(existingDocument->crossOriginEmbedderPolicy());

             // Fix up 'self' for blob: and data:, which is inherited from its embedding document or opener.
             auto* parentFrame = m_frame->tree().parent();
             if (auto* ownerFrame = parentFrame ? parentFrame : m_frame->loader().opener())
                 document->contentSecurityPolicy()->updateSourceSelf(ownerFrame->document()->securityOrigin());
         }
         document->contentSecurityPolicy()->setInsecureNavigationRequestsToUpgrade(existingDocument->contentSecurityPolicy()->takeNavigationRequestsToUpgrade());
     }

     Ref protectedFrame = *m_frame;

     m_frame->loader().didBeginDocument(dispatch);

     document->implicitOpen();

     // We grab a reference to the parser so that we'll always send data to the
     // original parser, even if the document acquires a new parser (e.g., via
     // document.open).
     m_parser = document->parser();

     if (m_frame->view() && m_frame->loader().client().hasHTMLView())
         m_frame->view()->setContentsSize(IntSize());

     m_state = State::Started;
     return true;
 }

 TextResourceDecoder& DocumentWriter::decoder()
 {
     if (!m_decoder) {
         m_decoder = TextResourceDecoder::create(m_mimeType,
             m_frame->settings().defaultTextEncodingName(),
             m_frame->settings().usesEncodingDetector());
         Frame* parentFrame = m_frame->tree().parent();
         // Set the hint encoding to the parent frame encoding only if
         // the parent and the current frames share the security origin.
         // We impose this condition because somebody can make a child frame
         // containing a carefully crafted html/javascript in one encoding
         // that can be mistaken for hintEncoding (or related encoding) by
         // an auto detector. When interpreted in the latter, it could be
         // an attack vector.
         // FIXME: This might be too cautious for non-7bit-encodings and
         // we may consider relaxing this later after testing.
         if (canReferToParentFrameEncoding(m_frame.get(), parentFrame))
             m_decoder->setHintEncoding(parentFrame->document()->decoder());
         if (m_encoding.isEmpty()) {
             if (canReferToParentFrameEncoding(m_frame.get(), parentFrame))
                 m_decoder->setEncoding(parentFrame->document()->textEncoding(), TextResourceDecoder::EncodingFromParentFrame);
         } else {
             m_decoder->setEncoding(m_encoding,
                 m_encodingWasChosenByUser ? TextResourceDecoder::UserChosenEncoding : TextResourceDecoder::EncodingFromHTTPHeader);
         }
         m_frame->document()->setDecoder(m_decoder.get());
     }
     return *m_decoder;
 }

 void DocumentWriter::reportDataReceived()
 {
     ASSERT(m_decoder);
     if (m_hasReceivedSomeData)
         return;
     m_hasReceivedSomeData = true;
     if (m_decoder->encoding().usesVisualOrdering())
         m_frame->document()->setVisuallyOrdered();
     m_frame->document()->resolveStyle(Document::ResolveStyleType::Rebuild);
 }

 void DocumentWriter::addData(const SharedBuffer& data)
 {
     // FIXME: Change these to ASSERT once https://bugs.webkit.org/show_bug.cgi?id=80427 has been resolved.
     RELEASE_ASSERT(m_state != State::NotStarted);
     if (m_state == State::Finished) {
         ASSERT_NOT_REACHED();
         return;
     }
     ASSERT(m_parser);
     m_parser->appendBytes(*this, data.data(), data.size());
 }

 void DocumentWriter::insertDataSynchronously(const String& markup)
 {
     ASSERT(m_state != State::NotStarted);
     ASSERT(m_state != State::Finished);
     ASSERT(m_parser);
     m_parser->insert(markup);
 }

 void DocumentWriter::end()
 {
     ASSERT(m_frame->page());
     ASSERT(m_frame->document());

     // The parser is guaranteed to be released after this point. begin() would
     // have to be called again before we can start writing more data.
     m_state = State::Finished;

     // http://bugs.webkit.org/show_bug.cgi?id=10854
     // The frame's last ref may be removed and it can be deleted by checkCompleted(),
     // so we'll add a protective refcount
     Ref<Frame> protect(*m_frame);

     if (!m_parser)
         return;
     // FIXME: m_parser->finish() should imply m_parser->flush().
     m_parser->flush(*this);
     if (!m_parser)
         return;
     m_parser->finish();
     m_parser = nullptr;
 }

 void DocumentWriter::setEncoding(const String& name, IsEncodingUserChosen isUserChosen)
 {
     m_encoding = name;
     m_encodingWasChosenByUser = isUserChosen == IsEncodingUserChosen::Yes;
 }

 void DocumentWriter::setFrame(Frame& frame)
 {
     m_frame = frame;
 }

 void DocumentWriter::setDocumentWasLoadedAsPartOfNavigation()
 {
     ASSERT(m_parser && !m_parser->isStopped());
     m_parser->setDocumentWasLoadedAsPartOfNavigation();
 }

 } // namespace WebCore
	/*
	* Copyright (C) 2010. Adam Barth. All rights reserved.
	* Copyright (C) 2016 Apple 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.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. Neither the name of Apple Inc. ("Apple") nor the names of
	* its contributors may be used to endorse or promote products derived
	* from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
	* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
	* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
	* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
	* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "DocumentWriter.h"

	#include "ContentSecurityPolicy.h"
	#include "DOMImplementation.h"
	#include "DOMWindow.h"
	#include "DocumentInlines.h"
	#include "DocumentLoader.h"
	#include "Frame.h"
	#include "FrameLoader.h"
	#include "FrameLoaderClient.h"
	#include "FrameLoaderStateMachine.h"
	#include "FrameView.h"
	#include "MIMETypeRegistry.h"
	#include "PluginDocument.h"
	#include "RawDataDocumentParser.h"
	#include "ScriptController.h"
	#include "ScriptableDocumentParser.h"
	#include "SecurityOrigin.h"
	#include "SecurityOriginPolicy.h"
	#include "SecurityPolicy.h"
	#include "SegmentedString.h"
	#include "Settings.h"
	#include "SinkDocument.h"
	#include "TextResourceDecoder.h"
	#include <wtf/Ref.h>

	namespace WebCore {

	static inline bool canReferToParentFrameEncoding(const Frame* frame, const Frame* parentFrame)
	{
	if (is<XMLDocument>(frame->document()))
	return false;
	return parentFrame && parentFrame->document()->securityOrigin().isSameOriginDomain(frame->document()->securityOrigin());
	}

	// This is only called by ScriptController::executeIfJavaScriptURL
	// and always contains the result of evaluating a javascript: url.
	// This is the <iframe src="javascript:'html'"> case.
	void DocumentWriter::replaceDocumentWithResultOfExecutingJavascriptURL(const String& source, Document* ownerDocument)
	{
	m_frame->loader().stopAllLoaders();

	// If we are in the midst of changing the frame's document, don't execute script
	// that modifies the document further:
	if (m_frame->documentIsBeingReplaced())
	return;

	begin(m_frame->document()->url(), true, ownerDocument);

	setEncoding("UTF-8"_s, IsEncodingUserChosen::No);

	// begin() might fire an unload event, which will result in a situation where no new document has been attached,
	// and the old document has been detached. Therefore, bail out if no document is attached.
	if (!m_frame->document())
	return;

	if (!source.isNull()) {
	if (!m_hasReceivedSomeData) {
	m_hasReceivedSomeData = true;
	m_frame->document()->setCompatibilityMode(DocumentCompatibilityMode::NoQuirksMode);
	}

	if (DocumentParser* parser = m_frame->document()->parser()) {
	auto utf8Source = source.utf8();
	parser->appendBytes(this, reinterpret_cast<const uint8_t>(utf8Source.data()), utf8Source.length());
	}
	}

	end();
	}

	void DocumentWriter::clear()
	{
	m_decoder = nullptr;
	m_hasReceivedSomeData = false;
	if (!m_encodingWasChosenByUser)
	m_encoding = String();
	}

	bool DocumentWriter::begin()
	{
	return begin(URL());
	}

	Ref<Document> DocumentWriter::createDocument(const URL& url, ScriptExecutionContextIdentifier documentIdentifier)
	{
	if (!m_frame->loader().stateMachine().isDisplayingInitialEmptyDocument() && m_frame->loader().client().shouldAlwaysUsePluginDocument(m_mimeType))
	return PluginDocument::create(*m_frame, url);
	#if PLATFORM(IOS_FAMILY)
	if (MIMETypeRegistry::isPDFMIMEType(m_mimeType) && (m_frame->isMainFrame() \|\| !m_frame->settings().useImageDocumentForSubframePDF()))
	return SinkDocument::create(*m_frame, url);
	#endif
	if (!m_frame->loader().client().hasHTMLView())
	return Document::createNonRenderedPlaceholder(*m_frame, url);
	return DOMImplementation::createDocument(m_mimeType, m_frame.get(), m_frame->settings(), url, documentIdentifier);
	}

	bool DocumentWriter::begin(const URL& urlReference, bool dispatch, Document* ownerDocument, ScriptExecutionContextIdentifier documentIdentifier)
	{
	// We grab a local copy of the URL because it's easy for callers to supply
	// a URL that will be deallocated during the execution of this function.
	// For example, see <https://bugs.webkit.org/show_bug.cgi?id=66360>.
	URL url = urlReference;

	// Create a new document before clearing the frame, because it may need to
	// inherit an aliased security context.
	Ref<Document> document = createDocument(url, documentIdentifier);

	// If the new document is for a Plugin but we're supposed to be sandboxed from Plugins,
	// then replace the document with one whose parser will ignore the incoming data (bug 39323)
	if (document->isPluginDocument() && document->isSandboxed(SandboxPlugins))
	document = SinkDocument::create(*m_frame, url);

	// FIXME: Do we need to consult the content security policy here about blocked plug-ins?

	bool shouldReuseDefaultView = m_frame->loader().stateMachine().isDisplayingInitialEmptyDocument()
	&& m_frame->document()->isSecureTransitionTo(url)
	&& (m_frame->window() && !m_frame->window()->wasWrappedWithoutInitializedSecurityOrigin() && m_frame->window()->mayReuseForNavigation());

	if (shouldReuseDefaultView) {
	ASSERT(m_frame->loader().documentLoader());
	if (auto* contentSecurityPolicy = m_frame->loader().documentLoader()->contentSecurityPolicy())
	shouldReuseDefaultView = !(contentSecurityPolicy->sandboxFlags() & SandboxOrigin);
	}

	// Temporarily extend the lifetime of the existing document so that FrameLoader::clear() doesn't destroy it as
	// we need to retain its ongoing set of upgraded requests in new navigation contexts per <http://www.w3.org/TR/upgrade-insecure-requests/>
	// and we may also need to inherit its Content Security Policy below.
	RefPtr<Document> existingDocument = m_frame->document();

	Function<void()> handleDOMWindowCreation = [this, document, shouldReuseDefaultView] {
	if (shouldReuseDefaultView)
	document->takeDOMWindowFrom(*m_frame->document());
	else
	document->createDOMWindow();
	};

	m_frame->loader().clear(document.ptr(), !shouldReuseDefaultView, !shouldReuseDefaultView, true, WTFMove(handleDOMWindowCreation));
	clear();

	// m_frame->loader().clear() might fire unload event which could remove the view of the document.
	// Bail out if document has no view.
	if (!document->view())
	return false;

	if (!shouldReuseDefaultView)
	m_frame->script().updatePlatformScriptObjects();

	m_frame->loader().setOutgoingReferrer(url);
	m_frame->setDocument(document.copyRef());

	if (m_decoder)
	document->setDecoder(m_decoder.get());
	if (ownerDocument) {
	// \|document\| is the result of evaluating a JavaScript URL.
	document->setCookieURL(ownerDocument->cookieURL());
	document->setSecurityOriginPolicy(ownerDocument->securityOriginPolicy());
	document->setStrictMixedContentMode(ownerDocument->isStrictMixedContentMode());
	document->setCrossOriginEmbedderPolicy(ownerDocument->crossOriginEmbedderPolicy());

	document->setContentSecurityPolicy(makeUnique<ContentSecurityPolicy>(URL { url }, document));
	document->contentSecurityPolicy()->copyStateFrom(ownerDocument->contentSecurityPolicy());
	document->contentSecurityPolicy()->setInsecureNavigationRequestsToUpgrade(ownerDocument->contentSecurityPolicy()->takeNavigationRequestsToUpgrade());
	} else if (existingDocument) {
	if (url.protocolIsData() \|\| url.protocolIsBlob()) {
	document->setContentSecurityPolicy(makeUnique<ContentSecurityPolicy>(URL { url }, document));
	document->contentSecurityPolicy()->copyStateFrom(existingDocument->contentSecurityPolicy());
	document->setCrossOriginEmbedderPolicy(existingDocument->crossOriginEmbedderPolicy());

	// Fix up 'self' for blob: and data:, which is inherited from its embedding document or opener.
	auto* parentFrame = m_frame->tree().parent();
	if (auto* ownerFrame = parentFrame ? parentFrame : m_frame->loader().opener())
	document->contentSecurityPolicy()->updateSourceSelf(ownerFrame->document()->securityOrigin());
	}
	document->contentSecurityPolicy()->setInsecureNavigationRequestsToUpgrade(existingDocument->contentSecurityPolicy()->takeNavigationRequestsToUpgrade());
	}

	Ref protectedFrame = *m_frame;

	m_frame->loader().didBeginDocument(dispatch);

	document->implicitOpen();

	// We grab a reference to the parser so that we'll always send data to the
	// original parser, even if the document acquires a new parser (e.g., via
	// document.open).
	m_parser = document->parser();

	if (m_frame->view() && m_frame->loader().client().hasHTMLView())
	m_frame->view()->setContentsSize(IntSize());

	m_state = State::Started;
	return true;
	}

	TextResourceDecoder& DocumentWriter::decoder()
	{
	if (!m_decoder) {
	m_decoder = TextResourceDecoder::create(m_mimeType,
	m_frame->settings().defaultTextEncodingName(),
	m_frame->settings().usesEncodingDetector());
	Frame* parentFrame = m_frame->tree().parent();
	// Set the hint encoding to the parent frame encoding only if
	// the parent and the current frames share the security origin.
	// We impose this condition because somebody can make a child frame
	// containing a carefully crafted html/javascript in one encoding
	// that can be mistaken for hintEncoding (or related encoding) by
	// an auto detector. When interpreted in the latter, it could be
	// an attack vector.
	// FIXME: This might be too cautious for non-7bit-encodings and
	// we may consider relaxing this later after testing.
	if (canReferToParentFrameEncoding(m_frame.get(), parentFrame))
	m_decoder->setHintEncoding(parentFrame->document()->decoder());
	if (m_encoding.isEmpty()) {
	if (canReferToParentFrameEncoding(m_frame.get(), parentFrame))
	m_decoder->setEncoding(parentFrame->document()->textEncoding(), TextResourceDecoder::EncodingFromParentFrame);
	} else {
	m_decoder->setEncoding(m_encoding,
	m_encodingWasChosenByUser ? TextResourceDecoder::UserChosenEncoding : TextResourceDecoder::EncodingFromHTTPHeader);
	}
	m_frame->document()->setDecoder(m_decoder.get());
	}
	return *m_decoder;
	}

	void DocumentWriter::reportDataReceived()
	{
	ASSERT(m_decoder);
	if (m_hasReceivedSomeData)
	return;
	m_hasReceivedSomeData = true;
	if (m_decoder->encoding().usesVisualOrdering())
	m_frame->document()->setVisuallyOrdered();
	m_frame->document()->resolveStyle(Document::ResolveStyleType::Rebuild);
	}

	void DocumentWriter::addData(const SharedBuffer& data)
	{
	// FIXME: Change these to ASSERT once https://bugs.webkit.org/show_bug.cgi?id=80427 has been resolved.
	RELEASE_ASSERT(m_state != State::NotStarted);
	if (m_state == State::Finished) {
	ASSERT_NOT_REACHED();
	return;
	}
	ASSERT(m_parser);
	m_parser->appendBytes(*this, data.data(), data.size());
	}

	void DocumentWriter::insertDataSynchronously(const String& markup)
	{
	ASSERT(m_state != State::NotStarted);
	ASSERT(m_state != State::Finished);
	ASSERT(m_parser);
	m_parser->insert(markup);
	}

	void DocumentWriter::end()
	{
	ASSERT(m_frame->page());
	ASSERT(m_frame->document());

	// The parser is guaranteed to be released after this point. begin() would
	// have to be called again before we can start writing more data.
	m_state = State::Finished;

	// http://bugs.webkit.org/show_bug.cgi?id=10854
	// The frame's last ref may be removed and it can be deleted by checkCompleted(),
	// so we'll add a protective refcount
	Ref<Frame> protect(*m_frame);

	if (!m_parser)
	return;
	// FIXME: m_parser->finish() should imply m_parser->flush().
	m_parser->flush(*this);
	if (!m_parser)
	return;
	m_parser->finish();
	m_parser = nullptr;
	}

	void DocumentWriter::setEncoding(const String& name, IsEncodingUserChosen isUserChosen)
	{
	m_encoding = name;
	m_encodingWasChosenByUser = isUserChosen == IsEncodingUserChosen::Yes;
	}

	void DocumentWriter::setFrame(Frame& frame)
	{
	m_frame = frame;
	}

	void DocumentWriter::setDocumentWasLoadedAsPartOfNavigation()
	{
	ASSERT(m_parser && !m_parser->isStopped());
	m_parser->setDocumentWasLoadedAsPartOfNavigation();
	}

	} // namespace WebCore