[WIP] WebFonts cache-aware timeout adaption

third_party/WebKit/Source/platform/network/ResourceRequest.cpp

 /*
  * Copyright (C) 2003, 2006 Apple Computer, Inc.  All rights reserved.
  * Copyright (C) 2009, 2012 Google 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
@@ skipping 70 matching lines @@
   setFetchRequestMode(data->m_fetchRequestMode);
   setFetchCredentialsMode(data->m_fetchCredentialsMode);
   setFetchRedirectMode(data->m_fetchRedirectMode);
   setLoFiState(data->m_loFiState);
   m_referrerPolicy = data->m_referrerPolicy;
   m_didSetHTTPReferrer = data->m_didSetHTTPReferrer;
   m_checkForBrowserSideNavigation = data->m_checkForBrowserSideNavigation;
   m_uiStartTime = data->m_uiStartTime;
   m_isExternalRequest = data->m_isExternalRequest;
   m_inputPerfMetricReportPolicy = data->m_inputPerfMetricReportPolicy;
+  m_isCacheAwareLoadingActivated = data->m_isCacheAwareLoadingActivated;
+  m_savedCachePolicy = data->m_savedCachePolicy;
   m_redirectStatus = data->m_redirectStatus;
 }
 
 ResourceRequest::ResourceRequest(const ResourceRequest&) = default;
 
 ResourceRequest& ResourceRequest::operator=(const ResourceRequest&) = default;
 
 std::unique_ptr<CrossThreadResourceRequestData> ResourceRequest::copyData()
     const {
   std::unique_ptr<CrossThreadResourceRequestData> data =
@@ skipping 28 matching lines @@
   data->m_fetchRequestMode = m_fetchRequestMode;
   data->m_fetchCredentialsMode = m_fetchCredentialsMode;
   data->m_fetchRedirectMode = m_fetchRedirectMode;
   data->m_loFiState = m_loFiState;
   data->m_referrerPolicy = m_referrerPolicy;
   data->m_didSetHTTPReferrer = m_didSetHTTPReferrer;
   data->m_checkForBrowserSideNavigation = m_checkForBrowserSideNavigation;
   data->m_uiStartTime = m_uiStartTime;
   data->m_isExternalRequest = m_isExternalRequest;
   data->m_inputPerfMetricReportPolicy = m_inputPerfMetricReportPolicy;
+  data->m_isCacheAwareLoadingActivated = m_isCacheAwareLoadingActivated;
+  data->m_savedCachePolicy = m_savedCachePolicy;
   data->m_redirectStatus = m_redirectStatus;
   return data;
 }
 
 bool ResourceRequest::isEmpty() const {
   return m_url.isEmpty();
 }
 
 bool ResourceRequest::isNull() const {
   return m_url.isNull();
@@ skipping 13 matching lines @@
 
   m_url.setUser(String());
   m_url.setPass(String());
 }
 
 WebCachePolicy ResourceRequest::getCachePolicy() const {
   return m_cachePolicy;
 }
 
 void ResourceRequest::setCachePolicy(WebCachePolicy cachePolicy) {
-  m_cachePolicy = cachePolicy;
+  // TODO(shaochuan): This may be called after cache-aware loading is activated,
+  // deactivate if cache policy is set to unsupported value. Remove after cache
+  // policy is only set before cache-aware loading activation. crbug.com/632580
+  if (m_isCacheAwareLoadingActivated &&
+      !isCacheAwareLoadingSupported(cachePolicy))
+    deactivateCacheAwareLoading();
+
+  if (m_isCacheAwareLoadingActivated)
+    m_savedCachePolicy = cachePolicy;
+  else
+    m_cachePolicy = cachePolicy;
 }
 
 double ResourceRequest::timeoutInterval() const {
   return m_timeoutInterval;
 }
 
 void ResourceRequest::setTimeoutInterval(double timoutIntervalSeconds) {
   m_timeoutInterval = timoutIntervalSeconds;
 }
 
@@ skipping 202 matching lines @@
 
 bool ResourceRequest::cacheControlContainsNoStore() const {
   return cacheControlHeader().containsNoStore;
 }
 
 bool ResourceRequest::hasCacheValidatorFields() const {
   return !m_httpHeaderFields.get(HTTPNames::Last_Modified).isEmpty() ||
          !m_httpHeaderFields.get(HTTPNames::ETag).isEmpty();
 }
 
+bool ResourceRequest::isCacheAwareLoadingSupported(WebCachePolicy cachePolicy) {
+  switch (cachePolicy) {
+    case WebCachePolicy::BypassingCache:
+    case WebCachePolicy::ReturnCacheDataDontLoad:
+      return false;
+    case WebCachePolicy::UseProtocolCachePolicy:
+    case WebCachePolicy::ValidatingCacheData:
+    case WebCachePolicy::ReturnCacheDataElseLoad:
+      break;
+  }
+  return true;
+}
+
+void ResourceRequest::mayActivateCacheAwareLoading() {
+  DCHECK(!m_isCacheAwareLoadingActivated);
+  if (!isCacheAwareLoadingSupported(m_cachePolicy))
+    return;
+
+  m_savedCachePolicy = m_cachePolicy;
+  // TODO(shaochuan): Stale data may be retrieved with this flag. Switch to new
+  // flag to load from disk cache with validation when available in net.
+  // crbug.com/652649
+  m_cachePolicy = WebCachePolicy::ReturnCacheDataDontLoad;
+  m_isCacheAwareLoadingActivated = true;
+}
+
+void ResourceRequest::deactivateCacheAwareLoading() {
+  DCHECK(m_isCacheAwareLoadingActivated);
+  m_cachePolicy = m_savedCachePolicy;
+  m_isCacheAwareLoadingActivated = false;
+}
+
 void ResourceRequest::initialize(const KURL& url) {
   m_url = url;
   m_cachePolicy = WebCachePolicy::UseProtocolCachePolicy;
   m_timeoutInterval = s_defaultTimeoutInterval;
   m_httpMethod = HTTPNames::GET;
   m_allowStoredCredentials = true;
   m_reportUploadProgress = false;
   m_reportRawHeaders = false;
   m_hasUserGesture = false;
   m_downloadToFile = false;
@@ skipping 12 matching lines @@
   m_fetchRedirectMode = WebURLRequest::FetchRedirectModeFollow;
   m_referrerPolicy = ReferrerPolicyDefault;
   m_loFiState = WebURLRequest::LoFiUnspecified;
   m_didSetHTTPReferrer = false;
   m_checkForBrowserSideNavigation = true;
   m_uiStartTime = 0;
   m_isExternalRequest = false;
   m_inputPerfMetricReportPolicy = InputToLoadPerfMetricReportPolicy::NoReport;
   m_redirectStatus = RedirectStatus::NoRedirect;
   m_requestorOrigin = SecurityOrigin::createUnique();
+  m_isCacheAwareLoadingActivated = false;
+  m_savedCachePolicy = WebCachePolicy::UseProtocolCachePolicy;
 }
 
 }  // namespace blink