blob: aecf705697db8d2257e4fb072076962d31c02f6a [file] [log] [blame]
// Copyright 2014 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 <memory>
#include "base/macros.h"
#include "base/threading/thread_checker.h"
#include "mojo/public/cpp/bindings/binding_set.h"
#include "mojo/public/cpp/bindings/interface_ptr_set.h"
#include "services/device/public/mojom/time_zone_monitor.mojom.h"
template <class T>
class scoped_refptr;
namespace base {
class SequencedTaskRunner;
namespace device {
// TimeZoneMonitor watches the system time zone, and notifies renderers
// when it changes. Some renderer code caches the system time zone, so
// this notification is necessary to inform such code that cached
// timezone data may have become invalid. Due to sandboxing, it is not
// possible for renderer processes to monitor for system time zone
// changes themselves, so this must happen in the browser process.
// Sandboxing also may prevent renderer processes from reading the time
// zone when it does change, so platforms may have to deal with this in
// platform-specific ways:
// - Mac uses a sandbox hole defined in content/renderer/
// - Linux-based platforms use ProxyLocaltimeCallToBrowser in
// content/zygote/ and HandleLocaltime in
// content/browser/renderer_host/ to override
// localtime in renderer processes with custom code that calls
// localtime in the browser process via Chrome IPC.
class TimeZoneMonitor : public device::mojom::TimeZoneMonitor {
// Returns a new TimeZoneMonitor object (likely a subclass) specific to the
// platform. Inject |file_task_runner| to enable running blocking file
// operations on it when necessary.
static std::unique_ptr<TimeZoneMonitor> Create(
scoped_refptr<base::SequencedTaskRunner> file_task_runner);
~TimeZoneMonitor() override;
void Bind(device::mojom::TimeZoneMonitorRequest request);
// Notify all callbacks that the system time zone may have changed.
void NotifyClients();
base::ThreadChecker thread_checker_;
// device::mojom::device::mojom::TimeZoneMonitor:
void AddClient(device::mojom::TimeZoneMonitorClientPtr client) override;
mojo::BindingSet<device::mojom::TimeZoneMonitor> bindings_;
mojo::InterfacePtrSet<device::mojom::TimeZoneMonitorClient> clients_;
} // namespace device