Revert 148069 and 148060 to see if they were responsible for a perf regression

Source/WebCore/loader/SubresourceLoader.cpp

+/*
+ * Copyright (C) 2006, 2007, 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1.  Redistributions of source code must retain the above copyright
+ *     notice, this list of conditions and the following disclaimer. 
+ * 2.  Redistributions in binary form must reproduce the above copyright
+ *     notice, this list of conditions and the following disclaimer in the
+ *     documentation and/or other materials provided with the distribution. 
+ * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ *     its contributors may be used to endorse or promote products derived
+ *     from this software without specific prior written permission. 
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+#include "SubresourceLoader.h"
+
+#include "CachedResourceLoader.h"
+#include "Document.h"
+#include "DocumentLoader.h"
+#include "Frame.h"
+#include "FrameLoader.h"
+#include "Logging.h"
+#include "MemoryCache.h"
+#include "ResourceBuffer.h"
+#include "WebCoreMemoryInstrumentation.h"
+#include <wtf/RefCountedLeakCounter.h>
+#include <wtf/StdLibExtras.h>
+#include <wtf/text/CString.h>
+
+namespace WebCore {
+
+DEFINE_DEBUG_ONLY_GLOBAL(WTF::RefCountedLeakCounter, subresourceLoaderCounter, ("SubresourceLoader"));
+
+SubresourceLoader::SubresourceLoader(Frame* frame, CachedResource* resource, const ResourceLoaderOptions& options)
+    : ResourceLoader(frame, resource, options)
+{
+#ifndef NDEBUG
+    subresourceLoaderCounter.increment();
+#endif
+}
+
+SubresourceLoader::~SubresourceLoader()
+{
+    ASSERT(m_state != Initialized);
+    ASSERT(reachedTerminalState());
+#ifndef NDEBUG
+    subresourceLoaderCounter.decrement();
+#endif
+}
+
+PassRefPtr<SubresourceLoader> SubresourceLoader::create(Frame* frame, CachedResource* resource, const ResourceRequest& request, const ResourceLoaderOptions& options)
+{
+    RefPtr<SubresourceLoader> subloader(adoptRef(new SubresourceLoader(frame, resource, options)));
+    if (!subloader->init(request))
+        return 0;
+    return subloader.release();
+}
+
+bool SubresourceLoader::init(const ResourceRequest& request)
+{
+    if (!ResourceLoader::init(request))
+        return false;
+
+    ASSERT(!reachedTerminalState());
+    m_state = Initialized;
+    m_documentLoader->addSubresourceLoader(this);
+    return true;
+}
+
+void SubresourceLoader::willSendRequest(ResourceRequest& newRequest, const ResourceResponse& redirectResponse)
+{
+    // Store the previous URL because the call to ResourceLoader::willSendRequest will modify it.
+    KURL previousURL = request().url();
+    RefPtr<SubresourceLoader> protect(this);
+
+    ASSERT(!newRequest.isNull());
+    if (!redirectResponse.isNull()) {
+        if (!m_documentLoader->cachedResourceLoader()->canRequest(m_resource->type(), newRequest.url())) {
+            cancel();
+            return;
+        }
+        if (m_resource->type() == CachedResource::ImageResource && m_documentLoader->cachedResourceLoader()->shouldDeferImageLoad(newRequest.url())) {
+            cancel();
+            return;
+        }
+        m_resource->willSendRequest(newRequest, redirectResponse);
+    }
+
+    if (newRequest.isNull() || reachedTerminalState())
+        return;
+
+    ResourceLoader::willSendRequest(newRequest, redirectResponse);
+    if (newRequest.isNull())
+        cancel();
+}
+
+void SubresourceLoader::didReceiveResponse(const ResourceResponse& response)
+{
+    ASSERT(!response.isNull());
+    ASSERT(m_state == Initialized);
+
+    // Reference the object in this method since the additional processing can do
+    // anything including removing the last reference to this object; one example of this is 3266216.
+    RefPtr<SubresourceLoader> protect(this);
+
+    if (m_resource->resourceToRevalidate()) {
+        if (response.httpStatusCode() == 304) {
+            // 304 Not modified / Use local copy
+            // Existing resource is ok, just use it updating the expiration time.
+            m_resource->setResponse(response);
+            memoryCache()->revalidationSucceeded(m_resource, response);
+            if (!reachedTerminalState())
+                ResourceLoader::didReceiveResponse(response);
+            return;
+        }
+        // Did not get 304 response, continue as a regular resource load.
+        memoryCache()->revalidationFailed(m_resource);
+    }
+
+    m_resource->responseReceived(response);
+    if (reachedTerminalState())
+        return;
+    ResourceLoader::didReceiveResponse(response);
+
+    // FIXME: Main resources have a different set of rules for multipart than images do.
+    // Hopefully we can merge those 2 paths.
+    if (response.isMultipart() && m_resource->type() != CachedResource::MainResource) {
+        m_loadingMultipartContent = true;
+
+        // We don't count multiParts in a CachedResourceLoader's request count
+        m_requestCountTracker.clear();
+        if (!m_resource->isImage()) {
+            cancel();
+            return;
+        }
+    }
+
+    RefPtr<ResourceBuffer> buffer = resourceData();
+    if (m_loadingMultipartContent && buffer && buffer->size()) {
+        sendDataToResource(buffer->data(), buffer->size());
+        clearResourceData();
+        // Since a subresource loader does not load multipart sections progressively, data was delivered to the loader all at once.        
+        // After the first multipart section is complete, signal to delegates that this load is "finished" 
+        m_documentLoader->subresourceLoaderFinishedLoadingOnePart(this);
+        didFinishLoadingOnePart(0);
+    }
+
+    checkForHTTPStatusCodeError();
+}
+
+bool SubresourceLoader::checkForHTTPStatusCodeError()
+{
+    if (m_resource->response().httpStatusCode() < 400 || m_resource->shouldIgnoreHTTPStatusCodeErrors())
+        return false;
+
+    m_state = Finishing;
+    m_resource->error(CachedResource::LoadError);
+    cancel();
+    return true;
+}
+
+void SubresourceLoader::didReceiveCachedMetadata(const char* data, int length)
+{
+    ASSERT(m_state == Initialized);
+    ASSERT(!m_resource->resourceToRevalidate());
+    m_resource->setSerializedCachedMetadata(data, length);
+}
+
+void SubresourceLoader::didFinishLoading(double finishTime)
+{
+    if (m_state != Initialized)
+        return;
+    ASSERT(!reachedTerminalState());
+    ASSERT(!m_resource->resourceToRevalidate());
+    ASSERT(!m_resource->errorOccurred());
+    LOG(ResourceLoading, "Received '%s'.", m_resource->url().string().latin1().data());
+
+    RefPtr<SubresourceLoader> protect(this);
+    CachedResourceHandle<CachedResource> protectResource(m_resource);
+    m_state = Finishing;
+    m_resource->setLoadFinishTime(finishTime);
+    m_resource->data(resourceData(), true);
+    m_resource->finish();
+    ResourceLoader::didFinishLoading(finishTime);
+}
+
+void SubresourceLoader::didFail(const ResourceError& error)
+{
+    if (m_state != Initialized)
+        return;
+    ASSERT(!reachedTerminalState());
+    LOG(ResourceLoading, "Failed to load '%s'.\n", m_resource->url().string().latin1().data());
+
+    RefPtr<SubresourceLoader> protect(this);
+    CachedResourceHandle<CachedResource> protectResource(m_resource);
+    m_state = Finishing;
+    if (m_resource->resourceToRevalidate())
+        memoryCache()->revalidationFailed(m_resource);
+    m_resource->setResourceError(error);
+    m_resource->error(CachedResource::LoadError);
+    if (!m_resource->isPreloaded())
+        memoryCache()->remove(m_resource);
+    ResourceLoader::didFail(error);
+}
+
+void SubresourceLoader::releaseResources()
+{
+    ASSERT(!reachedTerminalState());
+    if (m_state != Uninitialized) {
+        m_requestCountTracker.clear();
+        m_documentLoader->cachedResourceLoader()->loadDone(m_resource);
+        if (reachedTerminalState())
+            return;
+        m_resource->stopLoading();
+        m_documentLoader->removeSubresourceLoader(this);
+    }
+    ResourceLoader::releaseResources();
+}
+
+}