AU: Try delta updates first, then full updates

src/platform/update_engine/action_pipe.h

 // Copyright (c) 2009 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_PIPE_H__
 #define CHROMEOS_PLATFORM_UPDATE_ENGINE_PIPE_H__
 
 #include <stdio.h>
 #include <iostream>
 #include <map>
@@ skipping 11 matching lines @@
 // This class serves as a temporary holding area for an object passed out
 // from one Action and into another Action. It's templated so that it may
 // contain any type of object that an Action outputs/inputs. Actions
 // cannot be bonded (i.e., connected with a pipe) if their output/input
 // object types differ (a compiler error will result).
 //
 // An ActionPipe is generally created with the Bond() method and owned by
 // the two Action objects. a shared_ptr is used so that when the last Action
 // pointing to an ActionPipe dies, the ActionPipe dies, too.
 
-using std::map;
-using std::string;
-using std::tr1::shared_ptr;
-
 namespace chromeos_update_engine {
 
 // Used by Actions an InputObjectType or OutputObjectType to specify that
 // for that type, no object is taken/given.
 class NoneType {};
 
 template<typename T>
 class Action;
 
 template<typename ObjectType>
 class ActionPipe {
  public:
   virtual ~ActionPipe() {
     LOG(INFO) << "ActionPipe died";
   }
 
   // This should be called by an Action on its input pipe.
   // Returns a reference to the stored object.
   const ObjectType& contents() const { return contents_; }
 
   // This should be called by an Action on its output pipe.
   // Stores a copy of the passed object in this pipe.
   void set_contents(const ObjectType& contents) { contents_ = contents; }
 
   // Bonds two Actions together with a new ActionPipe. The ActionPipe is
   // jointly owned by the two Actions and will be automatically destroyed
   // when the last Action is destroyed.
   template<typename FromAction, typename ToAction>
   static void Bond(FromAction* from, ToAction* to) {
-    shared_ptr<ActionPipe<ObjectType> > pipe(new ActionPipe<ObjectType>);
+    std::tr1::shared_ptr<ActionPipe<ObjectType> > pipe(
+        new ActionPipe<ObjectType>);
     from->set_out_pipe(pipe);
 
     to->set_in_pipe(pipe);  // If you get an error on this line, then
     // it most likely means that the From object's OutputObjectType is
     // different from the To object's InputObjectType.
   }
 
  private:
   ObjectType contents_;
 
   // The ctor is private. This is because this class should construct itself
   // via the static Bond() method.
   ActionPipe() {}
   DISALLOW_COPY_AND_ASSIGN(ActionPipe);
 };
 
 // Utility function
 template<typename FromAction, typename ToAction>
 void BondActions(FromAction* from, ToAction* to) {
   // TODO(adlr): find something like this that the compiler accepts:
   // COMPILE_ASSERT(typeof(typename FromAction::OutputObjectType) ==
   //                typeof(typename ToAction::InputObjectType),
   //     FromAction_OutputObjectType_doesnt_match_ToAction_InputObjectType);
   ActionPipe<typename FromAction::OutputObjectType>::Bond(from, to);
 }
 
 }  // namespace chromeos_update_engine
 
 #endif  // CHROMEOS_PLATFORM_UPDATE_ENGINE_PIPE_H__