Beispiel #1
0
void ApplicationCacheGroup::selectCache(Frame* frame, const URL& passedManifestURL)
{
    ASSERT(frame && frame->page());
    
    if (!frame->settings().offlineWebApplicationCacheEnabled())
        return;
    
    DocumentLoader* documentLoader = frame->loader().documentLoader();
    ASSERT(!documentLoader->applicationCacheHost()->applicationCache());

    if (passedManifestURL.isNull()) {
        selectCacheWithoutManifestURL(frame);        
        return;
    }

    // Don't access anything on disk if private browsing is enabled.
    if (frame->page()->usesEphemeralSession() || !frame->document()->securityOrigin()->canAccessApplicationCache(frame->tree().top().document()->securityOrigin())) {
        postListenerTask(ApplicationCacheHost::CHECKING_EVENT, documentLoader);
        postListenerTask(ApplicationCacheHost::ERROR_EVENT, documentLoader);
        return;
    }

    URL manifestURL(passedManifestURL);
    if (manifestURL.hasFragmentIdentifier())
        manifestURL.removeFragmentIdentifier();

    ApplicationCache* mainResourceCache = documentLoader->applicationCacheHost()->mainResourceApplicationCache();
    
    if (mainResourceCache) {
        if (manifestURL == mainResourceCache->group()->m_manifestURL) {
            // The cache may have gotten obsoleted after we've loaded from it, but before we parsed the document and saw cache manifest.
            if (mainResourceCache->group()->isObsolete())
                return;
            mainResourceCache->group()->associateDocumentLoaderWithCache(documentLoader, mainResourceCache);
            mainResourceCache->group()->update(frame, ApplicationCacheUpdateWithBrowsingContext);
        } else {
            // The main resource was loaded from cache, so the cache must have an entry for it. Mark it as foreign.
            URL resourceURL(documentLoader->responseURL());
            if (resourceURL.hasFragmentIdentifier())
                resourceURL.removeFragmentIdentifier();
            ApplicationCacheResource* resource = mainResourceCache->resourceForURL(resourceURL);
            bool inStorage = resource->storageID();
            resource->addType(ApplicationCacheResource::Foreign);
            if (inStorage)
                frame->page()->applicationCacheStorage().storeUpdatedType(resource, mainResourceCache);

            // Restart the current navigation from the top of the navigation algorithm, undoing any changes that were made
            // as part of the initial load.
            // The navigation will not result in the same resource being loaded, because "foreign" entries are never picked during navigation.
            frame->navigationScheduler().scheduleLocationChange(frame->document(), frame->document()->securityOrigin(), documentLoader->url(), frame->loader().referrer());
        }
        
        return;
    }
    
    // The resource was loaded from the network, check if it is a HTTP/HTTPS GET.    
    const ResourceRequest& request = frame->loader().activeDocumentLoader()->request();

    if (!ApplicationCache::requestIsHTTPOrHTTPSGet(request))
        return;

    // Check that the resource URL has the same scheme/host/port as the manifest URL.
    if (!protocolHostAndPortAreEqual(manifestURL, request.url()))
        return;

    ApplicationCacheGroup* group = frame->page()->applicationCacheStorage().findOrCreateCacheGroup(manifestURL);

    documentLoader->applicationCacheHost()->setCandidateApplicationCacheGroup(group);
    group->m_pendingMasterResourceLoaders.add(documentLoader);
    group->m_downloadingPendingMasterResourceLoadersCount++;

    ASSERT(!group->m_cacheBeingUpdated || group->m_updateStatus != Idle);
    group->update(frame, ApplicationCacheUpdateWithBrowsingContext);
}