Use precaching for more data: urls than just images.

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 208 matching lines @@
         return true;
     if (resource->stillNeedsLoad())
         return true;
     return request.options().synchronousPolicy == RequestSynchronously && resource->isLoading();
 }
 
 // Limit the number of URLs in m_validatedURLs to avoid memory bloat.
 // http://crbug.com/52411
 static const int kMaxValidatedURLsSize = 10000;
 
-void ResourceFetcher::requestLoadStarted(Resource* resource, const FetchRequest& request, ResourceLoadStartType type)
+void ResourceFetcher::requestLoadStarted(Resource* resource, const FetchRequest& request, ResourceLoadStartType type, bool isStaticData)
 {
     if (type == ResourceLoadingFromCache)
         notifyLoadedFromMemoryCache(resource);
 
-    if (request.resourceRequest().url().protocolIsData() || context().hasSubstituteData())
+    if (isStaticData)
         return;
 
     if (type == ResourceLoadingFromCache && !resource->stillNeedsLoad() && !m_validatedURLs.contains(request.resourceRequest().url())) {
         // Resources loaded from memory cache should be reported the first time they're used.
         OwnPtr<ResourceTimingInfo> info = ResourceTimingInfo::create(request.options().initiatorInfo.name, monotonicallyIncreasingTime(), resource->type() == Resource::MainResource);
         populateResourceTiming(info.get(), resource, true);
         m_scheduledResourceTimingReports.append(info.release());
         if (!m_resourceTimingReportTimer.isActive())
             m_resourceTimingReportTimer.startOneShot(0, FROM_HERE);
     }
 
     if (m_validatedURLs.size() >= kMaxValidatedURLsSize) {
         m_validatedURLs.clear();
     }
     m_validatedURLs.add(request.resourceRequest().url());
 }
 
 static PassRefPtr<TraceEvent::ConvertableToTraceFormat> urlForTraceEvent(const KURL& url)
 {
     RefPtr<TracedValue> value = TracedValue::create();
     value->setString("url", url.string());
     return value.release();
 }
 
-ResourcePtr<Resource> ResourceFetcher::requestResource(FetchRequest& request, const ResourceFactory& factory)
+void ResourceFetcher::preCacheData(const FetchRequest& request, const ResourceFactory& factory, const SubstituteData& substituteData)
+{
+    const KURL& url = request.resourceRequest().url();
+    ASSERT(url.protocolIsData() || substituteData.isValid());
+    if ((factory.type() == Resource::MainResource && !substituteData.isValid()) || factory.type() == Resource::Raw || factory.type() == Resource::Media)
+        return;
+
+    const String cacheIdentifier = getCacheIdentifier();
+    if (Resource* oldResource = memoryCache()->resourceForURL(url, cacheIdentifier)) {
+        if (!substituteData.isValid())
+            return;
+        memoryCache()->remove(oldResource);
+    }
+
+    WebString mimetype;
+    WebString charset;
+    RefPtr<SharedBuffer> data;
+    if (substituteData.isValid()) {
+        mimetype = substituteData.mimeType();
+        charset = substituteData.textEncoding();
+        data = substituteData.content();
+    } else {
+        data = PassRefPtr<SharedBuffer>(Platform::current()->parseDataURL(url, mimetype, charset));
+        if (!data)
+            return;
+    }
+    ResourceResponse response(url, mimetype, data->size(), charset, String());
+    response.setHTTPStatusCode(200);
+    response.setHTTPStatusText("OK");
+
+    ResourcePtr<Resource> resource = factory.create(request.resourceRequest(), request.charset());
+    resource->setNeedsSynchronousCacheHit(substituteData.forceSynchronousLoad());
+    resource->setOptions(request.options());
+    // FIXME: We should provide a body stream here.
+    resource->responseReceived(response, nullptr);
+    resource->setDataBufferingPolicy(BufferData);
+    if (data->size())
+        resource->setResourceBuffer(data);
+    resource->setIdentifier(createUniqueIdentifier());
+    resource->setCacheIdentifier(cacheIdentifier);
+    resource->finish();
+    memoryCache()->add(resource.get());
+    scheduleDocumentResourcesGC();
+}
+
+ResourcePtr<Resource> ResourceFetcher::requestResource(FetchRequest& request, const ResourceFactory& factory, const SubstituteData& substituteData)
 {
     ASSERT(request.options().synchronousPolicy == RequestAsynchronously || factory.type() == Resource::Raw);
 
     context().upgradeInsecureRequest(request);
     context().addClientHintsIfNecessary(request);
     context().addCSPHeaderIfNecessary(factory.type(), request);
 
+    bool isStaticData = request.resourceRequest().url().protocolIsData() || substituteData.isValid();
+    if (isStaticData)
+        preCacheData(request, factory, substituteData);
+
     KURL url = request.resourceRequest().url();
     TRACE_EVENT1("blink", "ResourceFetcher::requestResource", "url", urlForTraceEvent(url));
 
     WTF_LOG(ResourceLoading, "ResourceFetcher::requestResource '%s', charset '%s', priority=%d, forPreload=%u, type=%s", url.elidedString().latin1().data(), request.charset().latin1().data(), request.priority(), request.forPreload(), ResourceTypeName(factory.type()));
 
     // If only the fragment identifiers differ, it is the same resource.
     url = MemoryCache::removeFragmentIdentifierIfNeeded(url);
 
     if (!url.isValid())
         return nullptr;
@@ skipping 14 matching lines @@
             Vector<String> argv;
             argv.append(Resource::resourceTypeToString(factory.type(), request.options().initiatorInfo));
             argv.append(url);
             activityLogger->logEvent("blinkRequestResource", argv.size(), argv.data());
         }
     }
 
     // See if we can use an existing resource from the cache.
     ResourcePtr<Resource> resource = memoryCache()->resourceForURL(url, getCacheIdentifier());
 
-    const RevalidationPolicy policy = determineRevalidationPolicy(factory.type(), request, resource.get());
+    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);
         break;
@@ skipping 50 matching lines @@
             return request.options().synchronousPolicy == RequestSynchronously ? resource : nullptr;
         }
     }
 
     // FIXME: Temporarily leave main resource caching disabled for chromium,
     // see https://bugs.webkit.org/show_bug.cgi?id=107962. Before caching main
     // resources, we should be sure to understand the implications for memory
     // use.
     // Remove main resource from cache to prevent reuse.
     if (factory.type() == Resource::MainResource) {
-        ASSERT(policy != Use || context().hasSubstituteData());
+        ASSERT(policy != Use || substituteData.isValid());
         ASSERT(policy != Revalidate);
         memoryCache()->remove(resource.get());
     }
 
     requestLoadStarted(resource.get(), request, policy == Use ? ResourceLoadingFromCache : ResourceLoadingFromNetwork);
 
     ASSERT(resource->url() == url.string());
     m_documentResources.set(resource->url(), resource);
     return resource;
 }
@@ skipping 91 matching lines @@
     if (resource->isCacheValidator()) {
         const AtomicString& timingAllowOrigin = resource->resourceToRevalidate()->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) const
+ResourceFetcher::RevalidationPolicy ResourceFetcher::determineRevalidationPolicy(Resource::Type type, const FetchRequest& fetchRequest, Resource* existingResource, bool isStaticData) const
 {
     const ResourceRequest& request = fetchRequest.resourceRequest();
 
     if (!existingResource)
         return Load;
 
     // We already have a preload going for this URL.
     if (fetchRequest.forPreload() && existingResource->isPreloaded())
         return Use;
 
     // If the same URL has been loaded as a different type, we need to reload.
     if (existingResource->type() != type) {
         // FIXME: If existingResource is a Preload and the new type is LinkPrefetch
         // We really should discard the new prefetch since the preload has more
         // specific type information! crbug.com/379893
         // fast/dom/HTMLLinkElement/link-and-subresource-test hits this case.
         WTF_LOG(ResourceLoading, "ResourceFetcher::determineRevalidationPolicy reloading due to type mismatch.");
         return Reload;
     }
 
     // Do not load from cache if images are not enabled. The load for this image will be blocked
     // in ImageResource::load.
     if (FetchRequest::DeferredByClient == fetchRequest.defer())
         return Reload;
 
-    // Always use data uris.
-    // FIXME: Extend this to non-images.
-    if (type == Resource::Image && request.url().protocolIsData())
-        return Use;
-
-    // If a main resource was populated from a SubstituteData load, use it.
-    if (type == Resource::MainResource && context().hasSubstituteData())
-        return Use;
-
     if (!existingResource->canReuse(request))
         return Reload;
 
     // Never use cache entries for downloadToFile / useStreamOnResponse
     // requests. The data will be delivered through other paths.
     if (request.downloadToFile() || request.useStreamOnResponse())
         return Reload;
 
+    // If resource was populated from a SubstituteData load or data: url, use it.
+    if (isStaticData)

[Nate Chapin, 2015/08/14 20:48:46]

This needs to come after downloadToFile(), since data urls can require download
too.

+        return Use;
+
     // Certain requests (e.g., XHRs) might have manually set headers that require revalidation.
     // FIXME: In theory, this should be a Revalidate case. In practice, the MemoryCache revalidation path assumes a whole bunch
     // of things about how revalidation works that manual headers violate, so punt to Reload instead.
     if (request.isConditional())
         return Reload;
 
     // Don't reload resources while pasting.
     if (m_allowStaleResources)
         return Use;
 
@@ skipping 538 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
 }
 
 }