Revalidate using the same Resource, attempt #3

third_party/WebKit/Source/core/fetch/ResourceFetcher.cpp

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller (mueller@kde.org)
     Copyright (C) 2002 Waldo Bastian (bastian@kde.org)
     Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
     Copyright (C) 2009 Torch Mobile Inc. http://www.torchmobile.com/
 
     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
@@ skipping 358 matching lines @@
 
     const RevalidationPolicy policy = determineRevalidationPolicy(factory.type(), request, resource.get(), isStaticData);
     switch (policy) {
     case Reload:
         memoryCache()->remove(resource.get());
         // Fall through
     case Load:
         resource = createResourceForLoading(request, request.charset(), factory);
         break;
     case Revalidate:
-        resource = createResourceForRevalidation(request, resource.get(), factory);
+        initializeRevalidation(request, resource.get());
         break;
     case Use:
         memoryCache()->updateForAccess(resource.get());
         break;
     }
 
     if (!resource)
         return nullptr;
     if (resource->type() != factory.type()) {
         ASSERT(request.forPreload());
@@ skipping 78 matching lines @@
     if (request.cachePolicy() == UseProtocolCachePolicy)
         request.setCachePolicy(context().resourceRequestCachePolicy(request, type));
     if (request.requestContext() == WebURLRequest::RequestContextUnspecified)
         determineRequestContext(request, type);
     if (type == Resource::LinkPrefetch || type == Resource::LinkSubresource)
         request.setHTTPHeaderField("Purpose", "prefetch");
 
     context().addAdditionalRequestHeaders(request, (type == Resource::MainResource) ? FetchMainResource : FetchSubresource);
 }
 
-ResourcePtr<Resource> ResourceFetcher::createResourceForRevalidation(const FetchRequest& request, Resource* resource, const ResourceFactory& factory)
+void ResourceFetcher::initializeRevalidation(const FetchRequest& request, Resource* resource)
 {
     ASSERT(resource);
     ASSERT(memoryCache()->contains(resource));
     ASSERT(resource->isLoaded());
     ASSERT(resource->canUseCacheValidator());
-    ASSERT(!resource->resourceToRevalidate());
+    ASSERT(!resource->isCacheValidator());
     ASSERT(!context().isControlledByServiceWorker());
 
     ResourceRequest revalidatingRequest(resource->resourceRequest());
     revalidatingRequest.clearHTTPReferrer();
     initializeResourceRequest(revalidatingRequest, resource->type());
 
     const AtomicString& lastModified = resource->response().httpHeaderField("Last-Modified");
     const AtomicString& eTag = resource->response().httpHeaderField("ETag");
     if (!lastModified.isEmpty() || !eTag.isEmpty()) {
         ASSERT(context().cachePolicy() != CachePolicyReload);
         if (context().cachePolicy() == CachePolicyRevalidate)
             revalidatingRequest.setHTTPHeaderField("Cache-Control", "max-age=0");
     }
     if (!lastModified.isEmpty())
         revalidatingRequest.setHTTPHeaderField("If-Modified-Since", lastModified);
     if (!eTag.isEmpty())
         revalidatingRequest.setHTTPHeaderField("If-None-Match", eTag);
 
     double stalenessLifetime = resource->stalenessLifetime();
     if (std::isfinite(stalenessLifetime) && stalenessLifetime > 0) {
         revalidatingRequest.setHTTPHeaderField("Resource-Freshness", AtomicString(String::format("max-age=%.0lf,stale-while-revalidate=%.0lf,age=%.0lf", resource->freshnessLifetime(), stalenessLifetime, resource->currentAge())));
     }
 
-    ResourcePtr<Resource> newResource = factory.create(revalidatingRequest, resource->encoding());
-    WTF_LOG(ResourceLoading, "Resource %p created to revalidate %p", newResource.get(), resource);
-
-    newResource->setResourceToRevalidate(resource);
-    newResource->setCacheIdentifier(resource->cacheIdentifier());
-
-    memoryCache()->remove(resource);
-    memoryCache()->add(newResource.get());
-    return newResource;
+    resource->setRevalidatingRequest(revalidatingRequest);
 }
 
 ResourcePtr<Resource> ResourceFetcher::createResourceForLoading(FetchRequest& request, const String& charset, const ResourceFactory& factory)
 {
     const String cacheIdentifier = getCacheIdentifier();
     ASSERT(!memoryCache()->resourceForURL(request.resourceRequest().url(), cacheIdentifier));
 
     WTF_LOG(ResourceLoading, "Loading Resource for '%s'.", request.resourceRequest().url().elidedString().latin1().data());
 
     initializeResourceRequest(request.mutableResourceRequest(), factory.type());
     ResourcePtr<Resource> resource = factory.create(request.resourceRequest(), charset);
     resource->setCacheIdentifier(cacheIdentifier);
 
     memoryCache()->add(resource.get());
     return resource;
 }
 
 void ResourceFetcher::storeResourceTimingInitiatorInformation(Resource* resource)
 {
     if (resource->options().initiatorInfo.name == FetchInitiatorTypeNames::internal)
         return;
 
     OwnPtr<ResourceTimingInfo> info = ResourceTimingInfo::create(resource->options().initiatorInfo.name, monotonicallyIncreasingTime(), resource->type() == Resource::MainResource);
 
     if (resource->isCacheValidator()) {
-        const AtomicString& timingAllowOrigin = resource->resourceToRevalidate()->response().httpHeaderField("Timing-Allow-Origin");
+        const AtomicString& timingAllowOrigin = resource->response().httpHeaderField("Timing-Allow-Origin");
         if (!timingAllowOrigin.isEmpty())
             info->setOriginalTimingAllowOrigin(timingAllowOrigin);
     }
 
     if (resource->type() != Resource::MainResource || context().updateTimingInfoForIFrameNavigation(info.get()))
         m_resourceTimingInfoMap.add(resource, info.release());
 }
 
 ResourceFetcher::RevalidationPolicy ResourceFetcher::determineRevalidationPolicy(Resource::Type type, const FetchRequest& fetchRequest, Resource* existingResource, bool isStaticData) const
 {
@@ skipping 614 matching lines @@
     visitor->trace(m_archiveResourceCollection);
     visitor->trace(m_loaders);
     visitor->trace(m_nonBlockingLoaders);
 #if ENABLE(OILPAN)
     visitor->trace(m_preloads);
     visitor->trace(m_resourceTimingInfoMap);
 #endif
 }
 
 }