Source/WebCore/loader/ImageLoader.cpp - platform/external/webkit - Git at Google

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * Library General Public License for more details.
  *
  * You should have received a copy of the GNU Library General Public License
  * along with this library; see the file COPYING.LIB.  If not, write to
  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  * Boston, MA 02110-1301, USA.
  */

 #include "config.h"
 #include "ImageLoader.h"

 #include "CachedImage.h"
 #include "CachedResourceLoader.h"
 #include "Document.h"
 #include "Element.h"
 #include "HTMLNames.h"
 #include "HTMLObjectElement.h"
 #include "RenderImage.h"

 #if ENABLE(SVG)
 #include "RenderSVGImage.h"
 #endif
 #if ENABLE(VIDEO)
 #include "RenderVideo.h"
 #endif

 #if !ASSERT_DISABLED
 // ImageLoader objects are allocated as members of other objects, so generic pointer check would always fail.
 namespace WTF {

 template<> struct ValueCheck<WebCore::ImageLoader*> {
     typedef WebCore::ImageLoader* TraitType;
     static void checkConsistency(const WebCore::ImageLoader* p)
     {
         if (!p)
             return;
         ASSERT(p->element());
         ValueCheck<WebCore::Element*>::checkConsistency(p->element());
     }
 };

 }
 #endif

 namespace WebCore {

 class ImageEventSender {
     WTF_MAKE_NONCOPYABLE(ImageEventSender); WTF_MAKE_FAST_ALLOCATED;
 public:
     ImageEventSender(const AtomicString& eventType);

     void dispatchEventSoon(ImageLoader*);
     void cancelEvent(ImageLoader*);

     void dispatchPendingEvents();

 #if !ASSERT_DISABLED
     bool hasPendingEvents(ImageLoader* loader) { return m_dispatchSoonList.find(loader) != notFound; }
 #endif

 private:
     void timerFired(Timer<ImageEventSender>*);

     AtomicString m_eventType;
     Timer<ImageEventSender> m_timer;
     Vector<ImageLoader*> m_dispatchSoonList;
     Vector<ImageLoader*> m_dispatchingList;
 };

 static ImageEventSender& beforeLoadEventSender()
 {
     DEFINE_STATIC_LOCAL(ImageEventSender, sender, (eventNames().beforeloadEvent));
     return sender;
 }

 static ImageEventSender& loadEventSender()
 {
     DEFINE_STATIC_LOCAL(ImageEventSender, sender, (eventNames().loadEvent));
     return sender;
 }

 ImageLoader::ImageLoader(Element* element)
     : m_element(element)
     , m_image(0)
     , m_firedBeforeLoad(true)
     , m_firedLoad(true)
     , m_imageComplete(true)
     , m_loadManually(false)
 {
 }

 ImageLoader::~ImageLoader()
 {
     if (m_image)
         m_image->removeClient(this);

     ASSERT(!m_firedBeforeLoad || !beforeLoadEventSender().hasPendingEvents(this));
     if (!m_firedBeforeLoad)
         beforeLoadEventSender().cancelEvent(this);

     ASSERT(!m_firedLoad || !loadEventSender().hasPendingEvents(this));
     if (!m_firedLoad)
         loadEventSender().cancelEvent(this);
 }

 void ImageLoader::setImage(CachedImage* newImage)
 {
     ASSERT(m_failedLoadURL.isEmpty());
     CachedImage* oldImage = m_image.get();
     if (newImage != oldImage) {
         m_image = newImage;
         if (!m_firedBeforeLoad) {
             beforeLoadEventSender().cancelEvent(this);
             m_firedBeforeLoad = true;
         }
         if (!m_firedLoad) {
             loadEventSender().cancelEvent(this);
             m_firedLoad = true;
         }
         m_imageComplete = true;
         if (newImage)
             newImage->addClient(this);
         if (oldImage)
             oldImage->removeClient(this);
     }

     if (RenderImageResource* imageResource = renderImageResource())
         imageResource->resetAnimation();
 }

 void ImageLoader::updateFromElement()
 {
     // If we're not making renderers for the page, then don't load images.  We don't want to slow
     // down the raw HTML parsing case by loading images we don't intend to display.
     Document* document = m_element->document();
     if (!document->renderer())
         return;

     AtomicString attr = m_element->getAttribute(m_element->imageSourceAttributeName());

     if (attr == m_failedLoadURL)
         return;

     // Do not load any image if the 'src' attribute is missing or if it is
     // an empty string referring to a local file. The latter condition is
     // a quirk that preserves old behavior that Dashboard widgets
     // need (<rdar://problem/5994621>).
     CachedImage* newImage = 0;
     if (!(attr.isNull() || (attr.isEmpty() && document->baseURI().isLocalFile()))) {
         if (m_loadManually) {
             bool autoLoadOtherImages = document->cachedResourceLoader()->autoLoadImages();
             document->cachedResourceLoader()->setAutoLoadImages(false);
             newImage = new CachedImage(sourceURI(attr));
             newImage->setLoading(true);
             newImage->setOwningCachedResourceLoader(document->cachedResourceLoader());
             document->cachedResourceLoader()->m_documentResources.set(newImage->url(), newImage);
             document->cachedResourceLoader()->setAutoLoadImages(autoLoadOtherImages);
         } else
             newImage = document->cachedResourceLoader()->requestImage(sourceURI(attr));

         // If we do not have an image here, it means that a cross-site
         // violation occurred.
         m_failedLoadURL = !newImage ? attr : AtomicString();
     }

     CachedImage* oldImage = m_image.get();
     if (newImage != oldImage) {
         if (!m_firedBeforeLoad)
             beforeLoadEventSender().cancelEvent(this);
         if (!m_firedLoad)
             loadEventSender().cancelEvent(this);

         m_image = newImage;
         m_firedBeforeLoad = !newImage;
         m_firedLoad = !newImage;
         m_imageComplete = !newImage;

         if (newImage) {
             newImage->addClient(this);
             if (!m_element->document()->hasListenerType(Document::BEFORELOAD_LISTENER))
                 dispatchPendingBeforeLoadEvent();
             else
                 beforeLoadEventSender().dispatchEventSoon(this);
         }
         if (oldImage)
             oldImage->removeClient(this);
     }

     if (RenderImageResource* imageResource = renderImageResource())
         imageResource->resetAnimation();
 }

 void ImageLoader::updateFromElementIgnoringPreviousError()
 {
     // Clear previous error.
     m_failedLoadURL = AtomicString();
     updateFromElement();
 }

 void ImageLoader::notifyFinished(CachedResource*)
 {
     ASSERT(m_failedLoadURL.isEmpty());

     m_imageComplete = true;
     if (haveFiredBeforeLoadEvent())
         updateRenderer();

     if (m_firedLoad)
         return;

     loadEventSender().dispatchEventSoon(this);
 }

 RenderImageResource* ImageLoader::renderImageResource()
 {
     RenderObject* renderer = m_element->renderer();

     if (!renderer)
         return 0;

     if (renderer->isImage())
         return toRenderImage(renderer)->imageResource();

 #if ENABLE(SVG)
     if (renderer->isSVGImage())
         return toRenderSVGImage(renderer)->imageResource();
 #endif

 #if ENABLE(VIDEO)
     if (renderer->isVideo())
         return toRenderVideo(renderer)->imageResource();
 #endif

     return 0;
 }

 void ImageLoader::updateRenderer()
 {
     RenderImageResource* imageResource = renderImageResource();

     if (!imageResource)
         return;

     // Only update the renderer if it doesn't have an image or if what we have
     // is a complete image.  This prevents flickering in the case where a dynamic
     // change is happening between two images.
     CachedImage* cachedImage = imageResource->cachedImage();
     if (m_image != cachedImage && (m_imageComplete || !cachedImage))
         imageResource->setCachedImage(m_image.get());
 }

 void ImageLoader::dispatchPendingBeforeLoadEvent()
 {
     if (m_firedBeforeLoad)
         return;
     if (!m_image)
         return;
     if (!m_element->document()->attached())
         return;
     m_firedBeforeLoad = true;
     if (m_element->dispatchBeforeLoadEvent(m_image->url())) {
         updateRenderer();
         return;
     }
     if (m_image) {
         m_image->removeClient(this);
         m_image = 0;
     }
     loadEventSender().cancelEvent(this);

     if (m_element->hasTagName(HTMLNames::objectTag))
         static_cast<HTMLObjectElement*>(m_element)->renderFallbackContent();
 }

 void ImageLoader::dispatchPendingLoadEvent()
 {
     if (m_firedLoad)
         return;
     if (!m_image)
         return;
     if (!m_element->document()->attached())
         return;
     m_firedLoad = true;
     dispatchLoadEvent();
 }

 void ImageLoader::dispatchPendingBeforeLoadEvents()
 {
     beforeLoadEventSender().dispatchPendingEvents();
 }

 void ImageLoader::dispatchPendingLoadEvents()
 {
     loadEventSender().dispatchPendingEvents();
 }

 void ImageLoader::elementWillMoveToNewOwnerDocument()
 {
     setImage(0);
 }

 ImageEventSender::ImageEventSender(const AtomicString& eventType)
     : m_eventType(eventType)
     , m_timer(this, &ImageEventSender::timerFired)
 {
 }

 void ImageEventSender::dispatchEventSoon(ImageLoader* loader)
 {
     m_dispatchSoonList.append(loader);
     if (!m_timer.isActive())
         m_timer.startOneShot(0);
 }

 void ImageEventSender::cancelEvent(ImageLoader* loader)
 {
     // Remove instances of this loader from both lists.
     // Use loops because we allow multiple instances to get into the lists.
     size_t size = m_dispatchSoonList.size();
     for (size_t i = 0; i < size; ++i) {
         if (m_dispatchSoonList[i] == loader)
             m_dispatchSoonList[i] = 0;
     }
     size = m_dispatchingList.size();
     for (size_t i = 0; i < size; ++i) {
         if (m_dispatchingList[i] == loader)
             m_dispatchingList[i] = 0;
     }
     if (m_dispatchSoonList.isEmpty())
         m_timer.stop();
 }

 void ImageEventSender::dispatchPendingEvents()
 {
     // Need to avoid re-entering this function; if new dispatches are
     // scheduled before the parent finishes processing the list, they
     // will set a timer and eventually be processed.
     if (!m_dispatchingList.isEmpty())
         return;

     m_timer.stop();

     m_dispatchSoonList.checkConsistency();

     m_dispatchingList.swap(m_dispatchSoonList);
     size_t size = m_dispatchingList.size();
     for (size_t i = 0; i < size; ++i) {
         if (ImageLoader* loader = m_dispatchingList[i]) {
             if (m_eventType == eventNames().beforeloadEvent)
                 loader->dispatchPendingBeforeLoadEvent();
             else
                 loader->dispatchPendingLoadEvent();
         }
     }
     m_dispatchingList.clear();
 }

 void ImageEventSender::timerFired(Timer<ImageEventSender>*)
 {
     dispatchPendingEvents();
 }

 }
	/*
	* Copyright (C) 1999 Lars Knoll (knoll@kde.org)
	* (C) 1999 Antti Koivisto (koivisto@kde.org)
	* Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010 Apple Inc. All rights reserved.
	*
	* This library is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Library General Public
	* License as published by the Free Software Foundation; either
	* version 2 of the License, or (at your option) any later version.
	*
	* This library is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* Library General Public License for more details.
	*
	* You should have received a copy of the GNU Library General Public License
	* along with this library; see the file COPYING.LIB. If not, write to
	* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
	* Boston, MA 02110-1301, USA.
	*/

	#include "config.h"
	#include "ImageLoader.h"

	#include "CachedImage.h"
	#include "CachedResourceLoader.h"
	#include "Document.h"
	#include "Element.h"
	#include "HTMLNames.h"
	#include "HTMLObjectElement.h"
	#include "RenderImage.h"

	#if ENABLE(SVG)
	#include "RenderSVGImage.h"
	#endif
	#if ENABLE(VIDEO)
	#include "RenderVideo.h"
	#endif

	#if !ASSERT_DISABLED
	// ImageLoader objects are allocated as members of other objects, so generic pointer check would always fail.
	namespace WTF {

	template<> struct ValueCheck<WebCore::ImageLoader*> {
	typedef WebCore::ImageLoader* TraitType;
	static void checkConsistency(const WebCore::ImageLoader* p)
	{
	if (!p)
	return;
	ASSERT(p->element());
	ValueCheck<WebCore::Element*>::checkConsistency(p->element());
	}
	};

	}
	#endif

	namespace WebCore {

	class ImageEventSender {
	WTF_MAKE_NONCOPYABLE(ImageEventSender); WTF_MAKE_FAST_ALLOCATED;
	public:
	ImageEventSender(const AtomicString& eventType);

	void dispatchEventSoon(ImageLoader*);
	void cancelEvent(ImageLoader*);

	void dispatchPendingEvents();

	#if !ASSERT_DISABLED
	bool hasPendingEvents(ImageLoader* loader) { return m_dispatchSoonList.find(loader) != notFound; }
	#endif

	private:
	void timerFired(Timer<ImageEventSender>*);

	AtomicString m_eventType;
	Timer<ImageEventSender> m_timer;
	Vector<ImageLoader*> m_dispatchSoonList;
	Vector<ImageLoader*> m_dispatchingList;
	};

	static ImageEventSender& beforeLoadEventSender()
	{
	DEFINE_STATIC_LOCAL(ImageEventSender, sender, (eventNames().beforeloadEvent));
	return sender;
	}

	static ImageEventSender& loadEventSender()
	{
	DEFINE_STATIC_LOCAL(ImageEventSender, sender, (eventNames().loadEvent));
	return sender;
	}

	ImageLoader::ImageLoader(Element* element)
	: m_element(element)
	, m_image(0)
	, m_firedBeforeLoad(true)
	, m_firedLoad(true)
	, m_imageComplete(true)
	, m_loadManually(false)
	{
	}

	ImageLoader::~ImageLoader()
	{
	if (m_image)
	m_image->removeClient(this);

	ASSERT(!m_firedBeforeLoad \|\| !beforeLoadEventSender().hasPendingEvents(this));
	if (!m_firedBeforeLoad)
	beforeLoadEventSender().cancelEvent(this);

	ASSERT(!m_firedLoad \|\| !loadEventSender().hasPendingEvents(this));
	if (!m_firedLoad)
	loadEventSender().cancelEvent(this);
	}

	void ImageLoader::setImage(CachedImage* newImage)
	{
	ASSERT(m_failedLoadURL.isEmpty());
	CachedImage* oldImage = m_image.get();
	if (newImage != oldImage) {
	m_image = newImage;
	if (!m_firedBeforeLoad) {
	beforeLoadEventSender().cancelEvent(this);
	m_firedBeforeLoad = true;
	}
	if (!m_firedLoad) {
	loadEventSender().cancelEvent(this);
	m_firedLoad = true;
	}
	m_imageComplete = true;
	if (newImage)
	newImage->addClient(this);
	if (oldImage)
	oldImage->removeClient(this);
	}

	if (RenderImageResource* imageResource = renderImageResource())
	imageResource->resetAnimation();
	}

	void ImageLoader::updateFromElement()
	{
	// If we're not making renderers for the page, then don't load images. We don't want to slow
	// down the raw HTML parsing case by loading images we don't intend to display.
	Document* document = m_element->document();
	if (!document->renderer())
	return;

	AtomicString attr = m_element->getAttribute(m_element->imageSourceAttributeName());

	if (attr == m_failedLoadURL)
	return;

	// Do not load any image if the 'src' attribute is missing or if it is
	// an empty string referring to a local file. The latter condition is
	// a quirk that preserves old behavior that Dashboard widgets
	// need (<rdar://problem/5994621>).
	CachedImage* newImage = 0;
	if (!(attr.isNull() \|\| (attr.isEmpty() && document->baseURI().isLocalFile()))) {
	if (m_loadManually) {
	bool autoLoadOtherImages = document->cachedResourceLoader()->autoLoadImages();
	document->cachedResourceLoader()->setAutoLoadImages(false);
	newImage = new CachedImage(sourceURI(attr));
	newImage->setLoading(true);
	newImage->setOwningCachedResourceLoader(document->cachedResourceLoader());
	document->cachedResourceLoader()->m_documentResources.set(newImage->url(), newImage);
	document->cachedResourceLoader()->setAutoLoadImages(autoLoadOtherImages);
	} else
	newImage = document->cachedResourceLoader()->requestImage(sourceURI(attr));

	// If we do not have an image here, it means that a cross-site
	// violation occurred.
	m_failedLoadURL = !newImage ? attr : AtomicString();
	}

	CachedImage* oldImage = m_image.get();
	if (newImage != oldImage) {
	if (!m_firedBeforeLoad)
	beforeLoadEventSender().cancelEvent(this);
	if (!m_firedLoad)
	loadEventSender().cancelEvent(this);

	m_image = newImage;
	m_firedBeforeLoad = !newImage;
	m_firedLoad = !newImage;
	m_imageComplete = !newImage;

	if (newImage) {
	newImage->addClient(this);
	if (!m_element->document()->hasListenerType(Document::BEFORELOAD_LISTENER))
	dispatchPendingBeforeLoadEvent();
	else
	beforeLoadEventSender().dispatchEventSoon(this);
	}
	if (oldImage)
	oldImage->removeClient(this);
	}

	if (RenderImageResource* imageResource = renderImageResource())
	imageResource->resetAnimation();
	}

	void ImageLoader::updateFromElementIgnoringPreviousError()
	{
	// Clear previous error.
	m_failedLoadURL = AtomicString();
	updateFromElement();
	}

	void ImageLoader::notifyFinished(CachedResource*)
	{
	ASSERT(m_failedLoadURL.isEmpty());

	m_imageComplete = true;
	if (haveFiredBeforeLoadEvent())
	updateRenderer();

	if (m_firedLoad)
	return;

	loadEventSender().dispatchEventSoon(this);
	}

	RenderImageResource* ImageLoader::renderImageResource()
	{
	RenderObject* renderer = m_element->renderer();

	if (!renderer)
	return 0;

	if (renderer->isImage())
	return toRenderImage(renderer)->imageResource();

	#if ENABLE(SVG)
	if (renderer->isSVGImage())
	return toRenderSVGImage(renderer)->imageResource();
	#endif

	#if ENABLE(VIDEO)
	if (renderer->isVideo())
	return toRenderVideo(renderer)->imageResource();
	#endif

	return 0;
	}

	void ImageLoader::updateRenderer()
	{
	RenderImageResource* imageResource = renderImageResource();

	if (!imageResource)
	return;

	// Only update the renderer if it doesn't have an image or if what we have
	// is a complete image. This prevents flickering in the case where a dynamic
	// change is happening between two images.
	CachedImage* cachedImage = imageResource->cachedImage();
	if (m_image != cachedImage && (m_imageComplete \|\| !cachedImage))
	imageResource->setCachedImage(m_image.get());
	}

	void ImageLoader::dispatchPendingBeforeLoadEvent()
	{
	if (m_firedBeforeLoad)
	return;
	if (!m_image)
	return;
	if (!m_element->document()->attached())
	return;
	m_firedBeforeLoad = true;
	if (m_element->dispatchBeforeLoadEvent(m_image->url())) {
	updateRenderer();
	return;
	}
	if (m_image) {
	m_image->removeClient(this);
	m_image = 0;
	}
	loadEventSender().cancelEvent(this);

	if (m_element->hasTagName(HTMLNames::objectTag))
	static_cast<HTMLObjectElement*>(m_element)->renderFallbackContent();
	}

	void ImageLoader::dispatchPendingLoadEvent()
	{
	if (m_firedLoad)
	return;
	if (!m_image)
	return;
	if (!m_element->document()->attached())
	return;
	m_firedLoad = true;
	dispatchLoadEvent();
	}

	void ImageLoader::dispatchPendingBeforeLoadEvents()
	{
	beforeLoadEventSender().dispatchPendingEvents();
	}

	void ImageLoader::dispatchPendingLoadEvents()
	{
	loadEventSender().dispatchPendingEvents();
	}

	void ImageLoader::elementWillMoveToNewOwnerDocument()
	{
	setImage(0);
	}

	ImageEventSender::ImageEventSender(const AtomicString& eventType)
	: m_eventType(eventType)
	, m_timer(this, &ImageEventSender::timerFired)
	{
	}

	void ImageEventSender::dispatchEventSoon(ImageLoader* loader)
	{
	m_dispatchSoonList.append(loader);
	if (!m_timer.isActive())
	m_timer.startOneShot(0);
	}

	void ImageEventSender::cancelEvent(ImageLoader* loader)
	{
	// Remove instances of this loader from both lists.
	// Use loops because we allow multiple instances to get into the lists.
	size_t size = m_dispatchSoonList.size();
	for (size_t i = 0; i < size; ++i) {
	if (m_dispatchSoonList[i] == loader)
	m_dispatchSoonList[i] = 0;
	}
	size = m_dispatchingList.size();
	for (size_t i = 0; i < size; ++i) {
	if (m_dispatchingList[i] == loader)
	m_dispatchingList[i] = 0;
	}
	if (m_dispatchSoonList.isEmpty())
	m_timer.stop();
	}

	void ImageEventSender::dispatchPendingEvents()
	{
	// Need to avoid re-entering this function; if new dispatches are
	// scheduled before the parent finishes processing the list, they
	// will set a timer and eventually be processed.
	if (!m_dispatchingList.isEmpty())
	return;

	m_timer.stop();

	m_dispatchSoonList.checkConsistency();

	m_dispatchingList.swap(m_dispatchSoonList);
	size_t size = m_dispatchingList.size();
	for (size_t i = 0; i < size; ++i) {
	if (ImageLoader* loader = m_dispatchingList[i]) {
	if (m_eventType == eventNames().beforeloadEvent)
	loader->dispatchPendingBeforeLoadEvent();
	else
	loader->dispatchPendingLoadEvent();
	}
	}
	m_dispatchingList.clear();
	}

	void ImageEventSender::timerFired(Timer<ImageEventSender>*)
	{
	dispatchPendingEvents();
	}

	}