C++ SubframeLoader类代码示例

// FIXME: This should be unified with HTMLEmbedElement::updateWidget and
// moved down into HTMLPluginImageElement.cpp
void HTMLObjectElement::updateWidget(PluginCreationOption pluginCreationOption)
{
    ASSERT(!renderEmbeddedObject()->isPluginUnavailable());
    ASSERT(needsWidgetUpdate());
    setNeedsWidgetUpdate(false);
    // FIXME: This should ASSERT isFinishedParsingChildren() instead.
    if (!isFinishedParsingChildren())
        return;

    // FIXME: I'm not sure it's ever possible to get into updateWidget during a
    // removal, but just in case we should avoid loading the frame to prevent
    // security bugs.
    if (!SubframeLoadingDisabler::canLoadFrame(this))
        return;

    String url = this->url();
    String serviceType = this->serviceType();

    // FIXME: These should be joined into a PluginParameters class.
    Vector<String> paramNames;
    Vector<String> paramValues;
    parametersForPlugin(paramNames, paramValues, url, serviceType);

    // Note: url is modified above by parametersForPlugin.
    if (!allowedToLoadFrameURL(url))
        return;

    bool fallbackContent = hasFallbackContent();
    renderEmbeddedObject()->setHasFallbackContent(fallbackContent);

    // FIXME: It's sadness that we have this special case here.
    //        See http://trac.webkit.org/changeset/25128 and
    //        plugins/netscape-plugin-setwindow-size.html
    if (pluginCreationOption == CreateOnlyNonNetscapePlugins && wouldLoadAsNetscapePlugin(url, serviceType)) {
        // Ensure updateWidget() is called again during layout to create the Netscape plug-in.
        setNeedsWidgetUpdate(true);
        return;
    }

    RefPtr<HTMLObjectElement> protect(this); // beforeload and plugin loading can make arbitrary DOM mutations.
    bool beforeLoadAllowedLoad = guardedDispatchBeforeLoadEvent(url);
    if (!renderer()) // Do not load the plugin if beforeload removed this element or its renderer.
        return;

    SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
    bool success = beforeLoadAllowedLoad && hasValidClassId() && loader->requestObject(this, url, getNameAttribute(), serviceType, paramNames, paramValues);
    if (!success && fallbackContent)
        renderFallbackContent();
}

// FIXME: This should be unified with HTMLEmbedElement::updateWidget and
// moved down into HTMLPluginImageElement.cpp
void HTMLObjectElement::updateWidget(bool onlyCreateNonNetscapePlugins)
{
    ASSERT(!renderEmbeddedObject()->pluginCrashedOrWasMissing());
    // FIXME: We should ASSERT(needsWidgetUpdate()), but currently
    // FrameView::updateWidget() calls updateWidget(false) without checking if
    // the widget actually needs updating!
    setNeedsWidgetUpdate(false);
    // FIXME: This should ASSERT isFinishedParsingChildren() instead.
    if (!isFinishedParsingChildren())
        return;

    String url = this->url();
    
    // If the object does not specify a MIME type via a type attribute, but does
    // contain a classid attribute, try to map the classid to a MIME type.
    String serviceType = this->serviceType();
    if (serviceType.isEmpty())
        serviceType = serviceTypeForClassId(classId());

    // FIXME: These should be joined into a PluginParameters class.
    Vector<String> paramNames;
    Vector<String> paramValues;
    parametersForPlugin(paramNames, paramValues, url, serviceType);

    // Note: url is modified above by parametersForPlugin.
    if (!allowedToLoadFrameURL(url))
        return;

    bool fallbackContent = hasFallbackContent();
    renderEmbeddedObject()->setHasFallbackContent(fallbackContent);

    if (onlyCreateNonNetscapePlugins && wouldLoadAsNetscapePlugin(url, serviceType))
        return;

    bool beforeLoadAllowedLoad = dispatchBeforeLoadEvent(url);

    // beforeload events can modify the DOM, potentially causing
    // RenderWidget::destroy() to be called.  Ensure we haven't been
    // destroyed before continuing.
    // FIXME: Should this render fallback content?
    if (!renderer())
        return;

    SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
    bool success = beforeLoadAllowedLoad && loader->requestObject(this, url, getAttribute(nameAttr), serviceType, paramNames, paramValues);

    if (!success && fallbackContent)
        renderFallbackContent();
}

// FIXME: This should be unified with HTMLEmbedElement::updateWidget and
// moved down into HTMLPluginImageElement.cpp
void HTMLObjectElement::updateWidget(PluginCreationOption pluginCreationOption)
{
    ASSERT(!renderEmbeddedObject()->pluginCrashedOrWasMissing());
    // FIXME: We should ASSERT(needsWidgetUpdate()), but currently
    // FrameView::updateWidget() calls updateWidget(false) without checking if
    // the widget actually needs updating!
    setNeedsWidgetUpdate(false);
    // FIXME: This should ASSERT isFinishedParsingChildren() instead.
    if (!isFinishedParsingChildren())
        return;
    
    String url = this->url();
    String serviceType = this->serviceType();

    // FIXME: These should be joined into a PluginParameters class.
    Vector<String> paramNames;
    Vector<String> paramValues;
    parametersForPlugin(paramNames, paramValues, url, serviceType);

    // Note: url is modified above by parametersForPlugin.
    if (!allowedToLoadFrameURL(url))
        return;

    bool fallbackContent = hasFallbackContent();
    renderEmbeddedObject()->setHasFallbackContent(fallbackContent);

    if (pluginCreationOption == CreateOnlyNonNetscapePlugins && wouldLoadAsNetscapePlugin(url, serviceType))
        return;

    ASSERT(!m_inBeforeLoadEventHandler);
    m_inBeforeLoadEventHandler = true;
    bool beforeLoadAllowedLoad = dispatchBeforeLoadEvent(url);
    m_inBeforeLoadEventHandler = false;

    // beforeload events can modify the DOM, potentially causing
    // RenderWidget::destroy() to be called.  Ensure we haven't been
    // destroyed before continuing.
    // FIXME: Should this render fallback content?
    if (!renderer())
        return;

    RefPtr<HTMLObjectElement> protect(this); // Loading the plugin might remove us from the document.
    SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
    bool success = beforeLoadAllowedLoad && hasValidClassId() && loader->requestObject(this, url, getAttribute(nameAttr), serviceType, paramNames, paramValues);

    if (!success && fallbackContent)
        renderFallbackContent();
}

// FIXME: This should be unified with HTMLObjectElement::updateWidget and
// moved down into HTMLPluginImageElement.cpp
void HTMLEmbedElement::updateWidget(PluginCreationOption pluginCreationOption)
{
    ASSERT(!renderEmbeddedObject()->pluginCrashedOrWasMissing());
    ASSERT(needsWidgetUpdate());
    setNeedsWidgetUpdate(false);

    if (m_url.isEmpty() && m_serviceType.isEmpty())
        return;

    // Note these pass m_url and m_serviceType to allow better code sharing with
    // <object> which modifies url and serviceType before calling these.
    if (!allowedToLoadFrameURL(m_url))
        return;

    // FIXME: It's sadness that we have this special case here.
    //        See http://trac.webkit.org/changeset/25128 and
    //        plugins/netscape-plugin-setwindow-size.html
    if (pluginCreationOption == CreateOnlyNonNetscapePlugins && wouldLoadAsNetscapePlugin(m_url, m_serviceType)) {
        // Ensure updateWidget() is called again during layout to create the Netscape plug-in.
        setNeedsWidgetUpdate(true);
        return;
    }

    // FIXME: These should be joined into a PluginParameters class.
    Vector<String> paramNames;
    Vector<String> paramValues;
    parametersForPlugin(paramNames, paramValues);

    RefPtr<HTMLEmbedElement> protect(this); // Loading the plugin might remove us from the document.
    bool beforeLoadAllowedLoad = guardedDispatchBeforeLoadEvent(m_url);
    if (!beforeLoadAllowedLoad) {
        if (document()->isPluginDocument()) {
            // Plugins inside plugin documents load differently than other plugins. By the time
            // we are here in a plugin document, the load of the plugin (which is the plugin document's
            // main resource) has already started. We need to explicitly cancel the main resource load here.
            toPluginDocument(document())->cancelManualPluginLoad();
        }
        return;
    }
    if (!renderer()) // Do not load the plugin if beforeload removed this element or its renderer.
        return;

    SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
    // FIXME: beforeLoad could have detached the renderer!  Just like in the <object> case above.
    loader->requestObject(this, m_url, getNameAttribute(), m_serviceType, paramNames, paramValues);
}

// FIXME: This should be unified with HTMLObjectElement::updateWidget and
// moved down into HTMLPluginImageElement.cpp
void HTMLEmbedElement::updateWidget(PluginCreationOption pluginCreationOption)
{
    ASSERT(!renderEmbeddedObject()->pluginCrashedOrWasMissing());
    // FIXME: We should ASSERT(needsWidgetUpdate()), but currently
    // FrameView::updateWidget() calls updateWidget(false) without checking if
    // the widget actually needs updating!
    setNeedsWidgetUpdate(false);

    if (m_url.isEmpty() && m_serviceType.isEmpty())
        return;

    // Note these pass m_url and m_serviceType to allow better code sharing with
    // <object> which modifies url and serviceType before calling these.
    if (!allowedToLoadFrameURL(m_url))
        return;
    // FIXME: It's sadness that we have this special case here.
    //        See http://trac.webkit.org/changeset/25128 and
    //        plugins/netscape-plugin-setwindow-size.html
    if (pluginCreationOption == CreateOnlyNonNetscapePlugins && wouldLoadAsNetscapePlugin(m_url, m_serviceType))
        return;

    // FIXME: These should be joined into a PluginParameters class.
    Vector<String> paramNames;
    Vector<String> paramValues;
    parametersForPlugin(paramNames, paramValues);

    ASSERT(!m_inBeforeLoadEventHandler);
    m_inBeforeLoadEventHandler = true;
    bool beforeLoadAllowedLoad = dispatchBeforeLoadEvent(m_url);
    m_inBeforeLoadEventHandler = false;

    if (!beforeLoadAllowedLoad) {
        if (document()->isPluginDocument()) {
            // Plugins inside plugin documents load differently than other plugins. By the time
            // we are here in a plugin document, the load of the plugin (which is the plugin document's
            // main resource) has already started. We need to explicitly cancel the main resource load here.
            toPluginDocument(document())->cancelManualPluginLoad();
        }
        return;
    }

    SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
    // FIXME: beforeLoad could have detached the renderer!  Just like in the <object> case above.
    loader->requestObject(this, m_url, getAttribute(nameAttr), m_serviceType, paramNames, paramValues);
}

// FIXME: This function should not deal with url or serviceType!
void HTMLObjectElement::parametersForPlugin(Vector<String>& paramNames, Vector<String>& paramValues, String& url, String& serviceType)
{
    HashSet<StringImpl*, CaseFoldingHash> uniqueParamNames;
    String urlParameter;
    
    // Scan the PARAM children and store their name/value pairs.
    // Get the URL and type from the params if we don't already have them.
    for (Node* child = firstChild(); child; child = child->nextSibling()) {
        if (!child->hasTagName(paramTag))
            continue;

        HTMLParamElement* p = static_cast<HTMLParamElement*>(child);
        String name = p->name();
        if (name.isEmpty())
            continue;

        uniqueParamNames.add(name.impl());
        paramNames.append(p->name());
        paramValues.append(p->value());

        // FIXME: url adjustment does not belong in this function.
        if (url.isEmpty() && urlParameter.isEmpty() && (equalIgnoringCase(name, "src") || equalIgnoringCase(name, "movie") || equalIgnoringCase(name, "code") || equalIgnoringCase(name, "url")))
            urlParameter = stripLeadingAndTrailingHTMLSpaces(p->value());
        // FIXME: serviceType calculation does not belong in this function.
        if (serviceType.isEmpty() && equalIgnoringCase(name, "type")) {
            serviceType = p->value();
            size_t pos = serviceType.find(";");
            if (pos != notFound)
                serviceType = serviceType.left(pos);
        }
    }
    
    // When OBJECT is used for an applet via Sun's Java plugin, the CODEBASE attribute in the tag
    // points to the Java plugin itself (an ActiveX component) while the actual applet CODEBASE is
    // in a PARAM tag. See <http://java.sun.com/products/plugin/1.2/docs/tags.html>. This means
    // we have to explicitly suppress the tag's CODEBASE attribute if there is none in a PARAM,
    // else our Java plugin will misinterpret it. [4004531]
    String codebase;
    if (MIMETypeRegistry::isJavaAppletMIMEType(serviceType)) {
        codebase = "codebase";
        uniqueParamNames.add(codebase.impl()); // pretend we found it in a PARAM already
    }
    
    // Turn the attributes of the <object> element into arrays, but don't override <param> values.
    if (hasAttributes()) {
        for (unsigned i = 0; i < attributeCount(); ++i) {
            Attribute* it = attributeItem(i);
            const AtomicString& name = it->name().localName();
            if (!uniqueParamNames.contains(name.impl())) {
                paramNames.append(name.string());
                paramValues.append(it->value().string());
            }
        }
    }
    
    mapDataParamToSrc(&paramNames, &paramValues);
    
    // HTML5 says that an object resource's URL is specified by the object's data
    // attribute, not by a param element. However, for compatibility, allow the
    // resource's URL to be given by a param named "src", "movie", "code" or "url"
    // if we know that resource points to a plug-in.
    if (url.isEmpty() && !urlParameter.isEmpty()) {
        SubframeLoader* loader = document()->frame()->loader()->subframeLoader();
        if (loader->resourceWillUsePlugin(urlParameter, serviceType, shouldPreferPlugInsForImages()))
            url = urlParameter;
    }
}