chromeos/dbus/services/liveness_service_provider.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROMEOS_DBUS_SERVICES_LIVENESS_SERVICE_PROVIDER_H_
   6 #define CHROMEOS_DBUS_SERVICES_LIVENESS_SERVICE_PROVIDER_H_
   7
   8 #include <string>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/memory/ref_counted.h"
  13 #include "base/memory/weak_ptr.h"
  14 #include "chromeos/chromeos_export.h"
  15 #include "chromeos/dbus/services/cros_dbus_service.h"
  16 #include "dbus/exported_object.h"
  17
  18 namespace dbus {
  19 class MethodCall;
  20 class Response;
  21 }
  22
  23 namespace chromeos {
  24
  25 // This class exports a "CheckLiveness" D-Bus method that the session manager
  26 // calls periodically to confirm that Chrome's UI thread is responsive to D-Bus
  27 // messages.  It can be tested with the following command:
  28 //
  29 // % dbus-send --system --type=method_call --print-reply
  30 //     --dest=org.chromium.LibCrosService
  31 //     /org/chromium/LibCrosService
  32 //     org.chromium.LibCrosServiceInterface.CheckLiveness
  33 //
  34 // -> method return sender=:1.9 -> dest=:1.27 reply_serial=2
  35 //
  36 // (An empty response should be returned.)
  37 class CHROMEOS_EXPORT LivenessServiceProvider
  38     : public CrosDBusService::ServiceProviderInterface {
  39  public:
  40   LivenessServiceProvider();
  41   ~LivenessServiceProvider() override;
  42
  43   // CrosDBusService::ServiceProviderInterface overrides:
  44   void Start(scoped_refptr<dbus::ExportedObject> exported_object) override;
  45
  46  private:
  47   // Called from ExportedObject when CheckLiveness() is exported as a D-Bus
  48   // method or failed to be exported.
  49   void OnExported(const std::string& interface_name,
  50                   const std::string& method_name,
  51                   bool success);
  52
  53   // Called on UI thread in response to a D-Bus request.
  54   void CheckLiveness(dbus::MethodCall* method_call,
  55                      dbus::ExportedObject::ResponseSender response_sender);
  56
  57   // Keep this last so that all weak pointers will be invalidated at the
  58   // beginning of destruction.
  59   base::WeakPtrFactory<LivenessServiceProvider> weak_ptr_factory_;
  60
  61   DISALLOW_COPY_AND_ASSIGN(LivenessServiceProvider);
  62 };
  63
  64 }  // namespace chromeos
  65
  66 #endif  // CHROMEOS_DBUS_SERVICES_LIVENESS_SERVICE_PROVIDER_H_