chromeos: Don't spam logs with tlsdate D-Bus errors at boot.

chromeos/dbus/system_clock_client.cc

 // 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.
 
 #include "chromeos/dbus/system_clock_client.h"
 
 #include <stdint.h>
 
 #include "base/bind.h"
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "dbus/bus.h"
 #include "dbus/message.h"
 #include "dbus/object_path.h"
 #include "dbus/object_proxy.h"
 #include "third_party/cros_system_api/dbus/service_constants.h"
 
 namespace chromeos {
 
 // The SystemClockClient implementation used in production.
 class SystemClockClientImpl : public SystemClockClient {
  public:
   SystemClockClientImpl()
       : can_set_time_(false),
         can_set_time_initialized_(false),
-        system_clock_proxy_(NULL),
+        system_clock_proxy_(nullptr),
         weak_ptr_factory_(this) {}
 
   ~SystemClockClientImpl() override {}
 
   void AddObserver(Observer* observer) override {
     observers_.AddObserver(observer);
   }
 
   void RemoveObserver(Observer* observer) override {
     observers_.RemoveObserver(observer);
@@ skipping 14 matching lines @@
                                     dbus::ObjectProxy::EmptyResponseCallback());
   }
 
   bool CanSetTime() override { return can_set_time_; }
 
  protected:
   void Init(dbus::Bus* bus) override {
     system_clock_proxy_ = bus->GetObjectProxy(
         system_clock::kSystemClockServiceName,
         dbus::ObjectPath(system_clock::kSystemClockServicePath));
-
-    // Check whether the system clock can be set.
-    GetCanSet();
-
-    // Monitor the D-Bus signal for TimeUpdated changes.
     system_clock_proxy_->ConnectToSignal(
         system_clock::kSystemClockInterface,
         system_clock::kSystemClockUpdated,
         base::Bind(&SystemClockClientImpl::TimeUpdatedReceived,
                    weak_ptr_factory_.GetWeakPtr()),
         base::Bind(&SystemClockClientImpl::TimeUpdatedConnected,
                    weak_ptr_factory_.GetWeakPtr()));
+    system_clock_proxy_->WaitForServiceToBeAvailable(
+        base::Bind(&SystemClockClientImpl::ServiceInitiallyAvailable,
+                   weak_ptr_factory_.GetWeakPtr()));
   }
 
  private:
+  // Called once when the service initially becomes available (or immediately if
+  // it's already available).
+  void ServiceInitiallyAvailable(bool service_is_available) {
+    if (service_is_available)
+      GetCanSet();
+    else
+      LOG(ERROR) << "Failed to wait for D-Bus service availability";
+  }
+
   // Called when a TimeUpdated signal is received.
   void TimeUpdatedReceived(dbus::Signal* signal) {
     VLOG(1) << "TimeUpdated signal received: " << signal->ToString();
     dbus::MessageReader reader(signal);
     FOR_EACH_OBSERVER(Observer, observers_, SystemClockUpdated());
 
     // Check if the system clock can be changed now.
     GetCanSet();
   }
 
@@ skipping 29 matching lines @@
     FOR_EACH_OBSERVER(
         Observer, observers_, SystemClockCanSetTimeChanged(can_set_time));
   }
 
   // Check whether the time can be set.
   void GetCanSet() {
     dbus::MethodCall method_call(system_clock::kSystemClockInterface,
                                  system_clock::kSystemClockCanSet);
     dbus::MessageWriter writer(&method_call);
     system_clock_proxy_->CallMethod(
-        &method_call,
-        dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
+        &method_call, dbus::ObjectProxy::TIMEOUT_USE_DEFAULT,
         base::Bind(&SystemClockClientImpl::OnGetCanSet,
                    weak_ptr_factory_.GetWeakPtr()));
   }
 
   // Whether the time can be set. Value is false until the first
   // CanSetTime response is received.
   bool can_set_time_;
   bool can_set_time_initialized_;
   dbus::ObjectProxy* system_clock_proxy_;
   base::ObserverList<Observer> observers_;
 
   base::WeakPtrFactory<SystemClockClientImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SystemClockClientImpl);
 };
 
-void SystemClockClient::Observer::SystemClockUpdated() {
-}
-
-void SystemClockClient::Observer::SystemClockCanSetTimeChanged(
-    bool can_set_time) {
-}
-
-SystemClockClient::SystemClockClient() {
-}
-
-SystemClockClient::~SystemClockClient() {
-}
-
 // static
 SystemClockClient* SystemClockClient::Create() {
   return new SystemClockClientImpl();
 }
 
+SystemClockClient::SystemClockClient() {}
+
 }  // namespace chromeos