AU: Implement exponential back off for 500 and 503 HTTP response codes.

omaha_request_action.h

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_REQUEST_ACTION_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_REQUEST_ACTION_H__
 
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <fcntl.h>
@@ skipping 109 matching lines @@
   OmahaRequestAction(PrefsInterface* prefs,
                      const OmahaRequestParams& params,
                      OmahaEvent* event,
                      HttpFetcher* http_fetcher);
   virtual ~OmahaRequestAction();
   typedef ActionTraits<OmahaRequestAction>::InputObjectType InputObjectType;
   typedef ActionTraits<OmahaRequestAction>::OutputObjectType OutputObjectType;
   void PerformAction();
   void TerminateProcessing();
 
+  int GetHTTPResponseCode() { return http_fetcher_->http_response_code(); }
+
   // Debugging/logging
   static std::string StaticType() { return "OmahaRequestAction"; }
   std::string Type() const { return StaticType(); }
 
   // Delegate methods (see http_fetcher.h)
   virtual void ReceivedBytes(HttpFetcher *fetcher,
                              const char* bytes, int length);
   virtual void TransferComplete(HttpFetcher *fetcher, bool successful);
 
   // Returns true if this is an Event request, false if it's an UpdateCheck.
@@ skipping 29 matching lines @@
   // are sent to Omaha.
   int ping_active_days_;
   int ping_roll_call_days_;
 
   DISALLOW_COPY_AND_ASSIGN(OmahaRequestAction);
 };
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_OMAHA_REQUEST_ACTION_H__