Allow cache reuse of some requests with Cache-Control headers

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 296 matching lines @@
 
     return true;
 }
 
 bool ResourceRequest::isConditional() const
 {
     return (m_httpHeaderFields.contains("If-Match")
         || m_httpHeaderFields.contains("If-Modified-Since")
         || m_httpHeaderFields.contains("If-None-Match")
         || m_httpHeaderFields.contains("If-Range")
-        || m_httpHeaderFields.contains("If-Unmodified-Since")
-        || m_httpHeaderFields.contains("Cache-Control"));
+        || m_httpHeaderFields.contains("If-Unmodified-Since"));
+}
+
+
+static const AtomicString& cacheControlHeaderString()
+{
+    DEFINE_STATIC_LOCAL(const AtomicString, cacheControlHeader, ("cache-control", AtomicString::ConstructFromLiteral));
+    return cacheControlHeader;
+}
+
+static const AtomicString& pragmaHeaderString()
+{
+    DEFINE_STATIC_LOCAL(const AtomicString, pragmaHeader, ("pragma", AtomicString::ConstructFromLiteral));
+    return pragmaHeader;
+}
+
+bool ResourceRequest::cacheControlContainsNoCache()
+{
+    if (!m_cacheControlHeader.parsed)
+        m_cacheControlHeader = parseCacheControlDirectives(m_httpHeaderFields.get(cacheControlHeaderString()), m_httpHeaderFields.get(pragmaHeaderString()));
+    return m_cacheControlHeader.containsNoCache;
+}
+
+bool ResourceRequest::cacheControlContainsNoStore()
+{
+    if (!m_cacheControlHeader.parsed)
+        m_cacheControlHeader = parseCacheControlDirectives(m_httpHeaderFields.get(cacheControlHeaderString()), m_httpHeaderFields.get(pragmaHeaderString()));
+    return m_cacheControlHeader.containsNoStore;
+}
+
+bool ResourceRequest::hasCacheValidatorFields()
+{
+    DEFINE_STATIC_LOCAL(const AtomicString, lastModifiedHeader, ("last-modified", AtomicString::ConstructFromLiteral));
+    DEFINE_STATIC_LOCAL(const AtomicString, eTagHeader, ("etag", AtomicString::ConstructFromLiteral));
+    return !m_httpHeaderFields.get(lastModifiedHeader).isEmpty() || !m_httpHeaderFields.get(eTagHeader).isEmpty();
 }
 
 double ResourceRequest::defaultTimeoutInterval()
 {
     return s_defaultTimeoutInterval;
 }
 
 void ResourceRequest::setDefaultTimeoutInterval(double timeoutInterval)
 {
     s_defaultTimeoutInterval = timeoutInterval;
@@ skipping 23 matching lines @@
 // This is used by the loader to control the number of issued parallel load requests.
 unsigned initializeMaximumHTTPConnectionCountPerHost()
 {
     // The chromium network stack already handles limiting the number of
     // parallel requests per host, so there's no need to do it here.  Therefore,
     // this is set to a high value that should never be hit in practice.
     return 10000;
 }
 
 }