blob: 07456e12d5f69d9fe025c6fabdccce5dcee2dbd7 [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 "base/basictypes.h"
#include "base/callback_forward.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/shared_memory.h"
#include "base/memory/singleton.h"
#include "base/threading/thread_checker.h"
#include "content/browser/device_sensors/device_sensors_consts.h"
#include "content/common/content_export.h"
namespace content {
class DataFetcherSharedMemory;
// Owns the data fetcher for Device Motion and Orientation and keeps track of
// the number of consumers currently using the data. The data fetcher is stopped
// when there are no consumers.
class CONTENT_EXPORT DeviceInertialSensorService {
// Returns the DeviceInertialSensorService singleton.
static DeviceInertialSensorService* GetInstance();
// Increments the number of users of the provider. The Provider is running
// when there's > 0 users, and is paused when the count drops to 0.
// Must be called on the I/O thread.
void AddConsumer(ConsumerType consumer_type);
// Removes a consumer. Should be matched with an AddConsumer call.
// Must be called on the I/O thread.
void RemoveConsumer(ConsumerType cosumer_type);
// Returns the shared memory handle of the device motion data duplicated
// into the given process.
base::SharedMemoryHandle GetSharedMemoryHandleForProcess(
ConsumerType consumer_type, base::ProcessHandle handle);
// Stop/join with the background polling thread in |provider_|.
void Shutdown();
// Injects a custom data fetcher for testing purposes. This class takes
// ownership of the injected object.
void SetDataFetcherForTesting(DataFetcherSharedMemory* test_data_fetcher);
friend struct base::DefaultSingletonTraits<DeviceInertialSensorService>;
virtual ~DeviceInertialSensorService();
bool ChangeNumberConsumers(ConsumerType consumer_type, int delta);
int GetNumberConsumers(ConsumerType consumer_type) const;
int num_light_readers_;
int num_motion_readers_;
int num_orientation_readers_;
int num_orientation_absolute_readers_;
bool is_shutdown_;
scoped_ptr<DataFetcherSharedMemory> data_fetcher_;
base::ThreadChecker thread_checker_;
} // namespace content