Don't duplicate ResourceRequests and ResourceLoaderOptions on ResourceLoader

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 749 matching lines @@
         // it is a font that defers actually loading until the font is required. On the other hand,
         // a Resource can have a non-null ResourceLoader* but have isLoading() return false in a narrow window
         // during completion, because we set loading to false before notifying ResourceClients, but don't
         // clear the ResourceLoader pointer until the stack unwinds. If, inside the ResourceClient callbacks,
         // an event fires synchronously and an event handler re-requests the resource, we can reach this point
         // while not loading but having a ResourceLoader.
         if (existingResource->isLoading() || existingResource->loader())
             return Use;
     }
 
+    // Don't try to reuse an in-progress async request for a new sync request.
+    if (fetchRequest.options().synchronousPolicy == RequestSynchronously && existingResource->isLoading())

[hiroshige, 2016/03/10 00:24:38]

This doesn't Reload in non-RawResource cases, because Use might be returned at
Line 767.
XSLStyleSheetResource::fetchSynchronously() seems the only case? where
RequestSynchronously is used with XSLStyleSheet.
Shouldn't this case have higher (or highest) priority, because ResourceLoader
otherwise fails by ASSERT()?

[Nate Chapin, 2016/03/10 18:46:01]

Bumped priority up so that the only higher priority Use cases are preloading
(not relevant for XSL stylesheets or raw resources) and static data (where no
ResourceLoader is created).

+        return Reload;
+
     // CachePolicyReload always reloads
     if (cachePolicy == CachePolicyReload) {
         WTF_LOG(ResourceLoading, "ResourceFetcher::determineRevalidationPolicy reloading due to CachePolicyReload.");
         return Reload;
     }
 
     // We'll try to reload the resource if it failed last time.
     if (existingResource->errorOccurred()) {
         WTF_LOG(ResourceLoading, "ResourceFetcher::determineRevalidationPolicye reloading due to resource being in the error state");
         return Reload;
@@ skipping 71 matching lines @@
     // TODO(japhet): Once oilpan ships, the const auto&
     // can be replaced with a Resource*. Also, null checking
     // the resource probably won't be necesssary.
     for (const auto& documentResource : m_documentResources) {
         Resource* resource = documentResource.value.get();
         if (resource && resource->getType() == Resource::Image && resource->stillNeedsLoad() && !clientDefersImage(resource->url()))
             const_cast<Resource*>(resource)->load(this, defaultResourceOptions());
     }
 }
 
-void ResourceFetcher::redirectReceived(Resource* resource, const ResourceResponse& redirectResponse)
-{
-    ResourceTimingInfoMap::iterator it = m_resourceTimingInfoMap.find(resource);
-    if (it != m_resourceTimingInfoMap.end())
-        it->value->addRedirect(redirectResponse);
-}
-
 void ResourceFetcher::didLoadResource(Resource* resource)
 {
     context().didLoadResource(resource);
 }
 
 int ResourceFetcher::requestCount() const
 {
     return m_loaders ? m_loaders->size() : 0;
 }
 
@@ skipping 93 matching lines @@
 }
 
 void ResourceFetcher::didFailLoading(const Resource* resource, const ResourceError& error)
 {
     TRACE_EVENT_ASYNC_END0("blink.net", "Resource", resource);
     willTerminateResourceLoader(resource->loader());
     bool isInternalRequest = resource->options().initiatorInfo.name == FetchInitiatorTypeNames::internal;
     context().dispatchDidFail(resource->identifier(), error, isInternalRequest);
 }
 
-void ResourceFetcher::willSendRequest(unsigned long identifier, ResourceRequest& request, const ResourceResponse& redirectResponse, const FetchInitiatorInfo& initiatorInfo)
-{
-    context().dispatchWillSendRequest(identifier, request, redirectResponse, initiatorInfo);
-}
-
 void ResourceFetcher::didReceiveResponse(const Resource* resource, const ResourceResponse& response)
 {
     // If the response is fetched via ServiceWorker, the original URL of the response could be different from the URL of the request.
     // We check the URL not to load the resources which are forbidden by the page CSP.
     // https://w3c.github.io/webappsec-csp/#should-block-response
     if (response.wasFetchedViaServiceWorker()) {
         const KURL& originalURL = response.originalURLViaServiceWorker();
         if (!originalURL.isEmpty() && !context().allowResponse(resource->getType(), resource->resourceRequest(), originalURL, resource->options())) {
             resource->loader()->cancel();
             bool isInternalRequest = resource->options().initiatorInfo.name == FetchInitiatorTypeNames::internal;
@@ skipping 21 matching lines @@
 
 void ResourceFetcher::subresourceLoaderFinishedLoadingOnePart(ResourceLoader* loader)
 {
     if (!m_nonBlockingLoaders)
         m_nonBlockingLoaders = ResourceLoaderSet::create();
     m_nonBlockingLoaders->add(loader);
     m_loaders->remove(loader);
     didLoadResource(loader->cachedResource());
 }
 
-void ResourceFetcher::didInitializeResourceLoader(ResourceLoader* loader)
+void ResourceFetcher::willStartLoadingResource(Resource* resource, ResourceLoader* loader, ResourceRequest& request)
 {
     if (loader->cachedResource()->shouldBlockLoadEvent()) {
         if (!m_loaders)
             m_loaders = ResourceLoaderSet::create();
         m_loaders->add(loader);
     } else {
         if (!m_nonBlockingLoaders)
             m_nonBlockingLoaders = ResourceLoaderSet::create();
         m_nonBlockingLoaders->add(loader);
     }
+
+    context().willStartLoadingResource(request);
+    storeResourceTimingInitiatorInformation(resource);
+    TRACE_EVENT_ASYNC_BEGIN2("blink.net", "Resource", resource, "url", resource->url().getString().ascii(), "priority", resource->resourceRequest().priority());
+
+    context().dispatchWillSendRequest(resource->identifier(), request, ResourceResponse(), resource->options().initiatorInfo);
 }
 
 void ResourceFetcher::willTerminateResourceLoader(ResourceLoader* loader)
 {
     if (m_loaders && m_loaders->contains(loader))
         m_loaders->remove(loader);
     else if (m_nonBlockingLoaders && m_nonBlockingLoaders->contains(loader))
         m_nonBlockingLoaders->remove(loader);
     else
         ASSERT_NOT_REACHED();
 }
 
-void ResourceFetcher::willStartLoadingResource(Resource* resource, ResourceRequest& request)
-{
-    context().willStartLoadingResource(request);
-    storeResourceTimingInitiatorInformation(resource);
-    TRACE_EVENT_ASYNC_BEGIN2("blink.net", "Resource", resource, "url", resource->url().getString().ascii(), "priority", resource->resourceRequest().priority());
-}
-
 void ResourceFetcher::stopFetching()
 {
     if (m_nonBlockingLoaders)
         m_nonBlockingLoaders->cancelAll();
     if (m_loaders)
         m_loaders->cancelAll();
 }
 
 bool ResourceFetcher::isFetching() const
 {
     return m_loaders && !m_loaders->isEmpty();
 }
 
 void ResourceFetcher::setDefersLoading(bool defers)
 {
     if (m_loaders)
         m_loaders->setAllDefersLoading(defers);
     if (m_nonBlockingLoaders)
         m_nonBlockingLoaders->setAllDefersLoading(defers);
 }
 
 bool ResourceFetcher::defersLoading() const
 {
     return context().defersLoading();
 }
 
-bool ResourceFetcher::canAccessRedirect(Resource* resource, ResourceRequest& newRequest, const ResourceResponse& redirectResponse, ResourceLoaderOptions& options)

[Nate Chapin, 2016/03/09 22:35:54]

I'm not sure whether it's better to merge canAccessRedirect() in to
willFollowRedirect() or to leave it as a private helper.

+static bool isManualRedirectFetchRequest(const ResourceRequest& request)
 {
-    if (!context().canRequest(resource->getType(), newRequest, newRequest.url(), options, resource->isUnusedPreload(), FetchRequest::UseDefaultOriginRestrictionForType))
-        return false;
-    if (options.corsEnabled == IsCORSEnabled) {
-        SecurityOrigin* sourceOrigin = options.securityOrigin.get();
-        if (!sourceOrigin)
-            sourceOrigin = context().securityOrigin();
+    return request.fetchRedirectMode() == WebURLRequest::FetchRedirectModeManual && request.requestContext() == WebURLRequest::RequestContextFetch;
+}
 
-        String errorMessage;
-        StoredCredentials withCredentials = resource->lastResourceRequest().allowStoredCredentials() ? AllowStoredCredentials : DoNotAllowStoredCredentials;
-        if (!CrossOriginAccessControl::handleRedirect(sourceOrigin, newRequest, redirectResponse, withCredentials, options, errorMessage)) {
-            resource->setCORSFailed();
-            context().addConsoleMessage(errorMessage);
+bool ResourceFetcher::willFollowRedirect(Resource* resource, ResourceRequest& newRequest, const ResourceResponse& redirectResponse)
+{
+    if (!isManualRedirectFetchRequest(resource->resourceRequest())) {
+        if (!context().canRequest(resource->getType(), newRequest, newRequest.url(), resource->options(), resource->isUnusedPreload(), FetchRequest::UseDefaultOriginRestrictionForType))
             return false;
+        if (resource->options().corsEnabled == IsCORSEnabled) {
+            SecurityOrigin* sourceOrigin = resource->options().securityOrigin.get();
+            if (!sourceOrigin)
+                sourceOrigin = context().securityOrigin();
+
+            String errorMessage;
+            StoredCredentials withCredentials = resource->lastResourceRequest().allowStoredCredentials() ? AllowStoredCredentials : DoNotAllowStoredCredentials;
+            if (!CrossOriginAccessControl::handleRedirect(sourceOrigin, newRequest, redirectResponse, withCredentials, resource->mutableOptions(), errorMessage)) {
+                resource->setCORSFailed();
+                context().addConsoleMessage(errorMessage);
+                return false;
+            }
         }
+        if (resource->getType() == Resource::Image && shouldDeferImageLoad(newRequest.url()))
+            return false;
     }
-    if (resource->getType() == Resource::Image && shouldDeferImageLoad(newRequest.url()))
-        return false;
+
+    ResourceTimingInfoMap::iterator it = m_resourceTimingInfoMap.find(resource);
+    if (it != m_resourceTimingInfoMap.end())
+        it->value->addRedirect(redirectResponse);
+    context().dispatchWillSendRequest(resource->identifier(), newRequest, redirectResponse, resource->options().initiatorInfo);
     return true;
 }
 
 void ResourceFetcher::updateAllImageResourcePriorities()
 {
     if (!m_loaders)
         return;
 
     TRACE_EVENT0("blink", "ResourceLoadPriorityOptimizer::updateAllImageResourcePriorities");
     for (const auto& loader : m_loaders->hashSet()) {
@@ skipping 128 matching lines @@
     visitor->trace(m_loaders);
     visitor->trace(m_nonBlockingLoaders);
 #if ENABLE(OILPAN)
     visitor->trace(m_documentResources);
     visitor->trace(m_preloads);
     visitor->trace(m_resourceTimingInfoMap);
 #endif
 }
 
 } // namespace blink