1 // Copyright 2014 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 #include "content/browser/device_sensors/device_inertial_sensor_service.h"
6
7 #include "base/bind.h"
8 #include "base/logging.h"
9 #include "base/memory/singleton.h"
10 #include "content/browser/device_sensors/data_fetcher_shared_memory.h"
11
12 namespace content {
13
DeviceInertialSensorService()14 DeviceInertialSensorService::DeviceInertialSensorService()
15 : num_motion_readers_(0),
16 num_orientation_readers_(0),
17 is_shutdown_(false) {
18 }
19
~DeviceInertialSensorService()20 DeviceInertialSensorService::~DeviceInertialSensorService() {
21 }
22
GetInstance()23 DeviceInertialSensorService* DeviceInertialSensorService::GetInstance() {
24 return Singleton<DeviceInertialSensorService,
25 LeakySingletonTraits<DeviceInertialSensorService> >::get();
26 }
27
AddConsumer(ConsumerType consumer_type)28 void DeviceInertialSensorService::AddConsumer(ConsumerType consumer_type) {
29 if (!ChangeNumberConsumers(consumer_type, 1))
30 return;
31
32 DCHECK(GetNumberConsumers(consumer_type));
33
34 if (!data_fetcher_)
35 data_fetcher_.reset(new DataFetcherSharedMemory);
36 data_fetcher_->StartFetchingDeviceData(consumer_type);
37 }
38
RemoveConsumer(ConsumerType consumer_type)39 void DeviceInertialSensorService::RemoveConsumer(ConsumerType consumer_type) {
40 if (!ChangeNumberConsumers(consumer_type, -1))
41 return;
42
43 if (GetNumberConsumers(consumer_type) == 0)
44 data_fetcher_->StopFetchingDeviceData(consumer_type);
45 }
46
ChangeNumberConsumers(ConsumerType consumer_type,int delta)47 bool DeviceInertialSensorService::ChangeNumberConsumers(
48 ConsumerType consumer_type, int delta) {
49 DCHECK(thread_checker_.CalledOnValidThread());
50 if (is_shutdown_)
51 return false;
52
53 switch (consumer_type) {
54 case CONSUMER_TYPE_MOTION:
55 num_motion_readers_ += delta;
56 DCHECK_GE(num_motion_readers_, 0);
57 return true;
58 case CONSUMER_TYPE_ORIENTATION:
59 num_orientation_readers_ += delta;
60 DCHECK_GE(num_orientation_readers_ , 0);
61 return true;
62 default:
63 NOTREACHED();
64 }
65 return false;
66 }
67
GetNumberConsumers(ConsumerType consumer_type) const68 int DeviceInertialSensorService::GetNumberConsumers(
69 ConsumerType consumer_type) const {
70 switch (consumer_type) {
71 case CONSUMER_TYPE_MOTION:
72 return num_motion_readers_;
73 case CONSUMER_TYPE_ORIENTATION:
74 return num_orientation_readers_;
75 default:
76 NOTREACHED();
77 }
78 return 0;
79 }
80
81 base::SharedMemoryHandle
GetSharedMemoryHandleForProcess(ConsumerType consumer_type,base::ProcessHandle handle)82 DeviceInertialSensorService::GetSharedMemoryHandleForProcess(
83 ConsumerType consumer_type, base::ProcessHandle handle) {
84 DCHECK(thread_checker_.CalledOnValidThread());
85 return data_fetcher_->GetSharedMemoryHandleForProcess(consumer_type, handle);
86 }
87
Shutdown()88 void DeviceInertialSensorService::Shutdown() {
89 data_fetcher_.reset();
90 is_shutdown_ = true;
91 }
92
SetDataFetcherForTesting(DataFetcherSharedMemory * test_data_fetcher)93 void DeviceInertialSensorService::SetDataFetcherForTesting(
94 DataFetcherSharedMemory* test_data_fetcher) {
95 data_fetcher_.reset(test_data_fetcher);
96 }
97
98 } // namespace content
99