dbus: Make Bus::GetManagedObjects skip unavailable services.

dbus/object_manager.h

 // Copyright (c) 2013 The Chromium 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 DBUS_OBJECT_MANAGER_H_
 #define DBUS_OBJECT_MANAGER_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 53 matching lines @@
 //       : bus_(bus),
 //         weak_ptr_factory_(this) {
 //     object_manager_ = bus_->GetObjectManager(kServiceName, kManagerPath);
 //     object_manager_->RegisterInterface(kInterface, this);
 //   }
 //
 //   virtual ExampleClient::~ExampleClient() {
 //     object_manager_->UnregisterInterface(kInterface);
 //   }
 //
-// The D-Bus thread manager takes care of issuing the necessary call to
-// GetManagedObjects() after the implementation classes have been set up.
+// This class calls GetManagedObjects() asynchronously after the remote service
+// becomes available and additionally refreshes managed objects after the
+// service stops or restarts.
 //
 // The object manager interface class has one abstract method that must be
 // implemented by the class to create Properties structures on demand. As well
 // as implementing this, you will want to implement a public GetProperties()
 // method.
 //
 // Example:
 //   dbus::PropertySet* CreateProperties(dbus::ObjectProxy* object_proxy,
 //                                       const std::string& interface_name)
 //       override {
@@ skipping 145 matching lines @@
   //
   // BLOCKING CALL.
   void CleanUp();
 
  protected:
   virtual ~ObjectManager();
 
  private:
   friend class base::RefCountedThreadSafe<ObjectManager>;
 
+  // Callback for ObjectProxy::WaitForServiceToBeAvailable() that refreshes
+  // objects when the service becomes initially available if
+  // |signals_are_connected_| is already true.
+  void OnServiceInitiallyAvailable(bool service_is_available);
+
   // Connects the InterfacesAdded and InterfacesRemoved signals and calls
-  // GetManagedObjects. Called from OnSetupMatchRuleAndFilterComplete.
+  // GetManagedObjects if |service_initially_available_| is already true. Called
+  // from OnSetupMatchRuleAndFilterComplete.
   void InitializeObjects();
 
   // Called from the constructor to add a match rule for PropertiesChanged
   // signals on the DBus thread and set up a corresponding filter function.
   bool SetupMatchRuleAndFilter();
 
   // Called on the origin thread once the match rule and filter have been set
   // up. |success| is false, if an error occurred during set up; it's true
   // otherwise.
   void OnSetupMatchRuleAndFilterComplete(bool success);
@@ skipping 66 matching lines @@
 
   Bus* bus_;
   std::string service_name_;
   std::string service_name_owner_;
   std::string match_rule_;
   ObjectPath object_path_;
   ObjectProxy* object_proxy_;
   bool setup_success_;
   bool cleanup_called_;
 
+  // Set to true by OnServiceInitiallyAvailable() once the service becomes
+  // initially available.
+  bool service_initially_available_;
+
+  // Set to true by InitializeObjects() once signals are connected.
+  bool signals_are_connected_;
+
   // Maps the name of an interface to the implementation class used for
   // instantiating PropertySet structures for that interface's properties.
   typedef std::map<std::string, Interface*> InterfaceMap;
   InterfaceMap interface_map_;
 
   // Each managed object consists of a ObjectProxy used to make calls
   // against that object and a collection of D-Bus interface names and their
   // associated PropertySet structures.
   struct Object {
     Object();
@@ skipping 16 matching lines @@
   // Note: This should remain the last member so it'll be destroyed and
   // invalidate its weak pointers before any other members are destroyed.
   base::WeakPtrFactory<ObjectManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ObjectManager);
 };
 
 }  // namespace dbus
 
 #endif  // DBUS_OBJECT_MANAGER_H_