1 // Copyright 2013 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_orientation/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_orientation/data_fetcher_shared_memory.h"
11 #include "content/public/browser/render_process_host.h"
12
13 namespace content {
14
DeviceInertialSensorService()15 DeviceInertialSensorService::DeviceInertialSensorService()
16 : num_motion_readers_(0),
17 num_orientation_readers_(0),
18 is_shutdown_(false) {
19 }
20
~DeviceInertialSensorService()21 DeviceInertialSensorService::~DeviceInertialSensorService() {
22 }
23
GetInstance()24 DeviceInertialSensorService* DeviceInertialSensorService::GetInstance() {
25 return Singleton<DeviceInertialSensorService,
26 LeakySingletonTraits<DeviceInertialSensorService> >::get();
27 }
28
AddConsumer(ConsumerType consumer_type)29 void DeviceInertialSensorService::AddConsumer(ConsumerType consumer_type) {
30 if (!ChangeNumberConsumers(consumer_type, 1))
31 return;
32
33 DCHECK(GetNumberConsumers(consumer_type));
34
35 if (!data_fetcher_)
36 data_fetcher_.reset(new DataFetcherSharedMemory);
37 data_fetcher_->StartFetchingDeviceData(consumer_type);
38 }
39
RemoveConsumer(ConsumerType consumer_type)40 void DeviceInertialSensorService::RemoveConsumer(ConsumerType consumer_type) {
41 if (!ChangeNumberConsumers(consumer_type, -1))
42 return;
43
44 if (GetNumberConsumers(consumer_type) == 0)
45 data_fetcher_->StopFetchingDeviceData(consumer_type);
46 }
47
ChangeNumberConsumers(ConsumerType consumer_type,int delta)48 bool DeviceInertialSensorService::ChangeNumberConsumers(
49 ConsumerType consumer_type, int delta) {
50 DCHECK(thread_checker_.CalledOnValidThread());
51 if (is_shutdown_)
52 return false;
53
54 switch (consumer_type) {
55 case CONSUMER_TYPE_MOTION:
56 num_motion_readers_ += delta;
57 DCHECK(num_motion_readers_ >= 0);
58 return true;
59 case CONSUMER_TYPE_ORIENTATION:
60 num_orientation_readers_ += delta;
61 DCHECK(num_orientation_readers_ >= 0);
62 return true;
63 default:
64 NOTREACHED();
65 }
66 return false;
67 }
68
GetNumberConsumers(ConsumerType consumer_type) const69 int DeviceInertialSensorService::GetNumberConsumers(
70 ConsumerType consumer_type) const {
71 switch (consumer_type) {
72 case CONSUMER_TYPE_MOTION:
73 return num_motion_readers_;
74 case CONSUMER_TYPE_ORIENTATION:
75 return num_orientation_readers_;
76 default:
77 NOTREACHED();
78 }
79 return 0;
80 }
81
82 base::SharedMemoryHandle
GetSharedMemoryHandleForProcess(ConsumerType consumer_type,base::ProcessHandle handle)83 DeviceInertialSensorService::GetSharedMemoryHandleForProcess(
84 ConsumerType consumer_type, base::ProcessHandle handle) {
85 DCHECK(thread_checker_.CalledOnValidThread());
86 return data_fetcher_->GetSharedMemoryHandleForProcess(consumer_type, handle);
87 }
88
Shutdown()89 void DeviceInertialSensorService::Shutdown() {
90 data_fetcher_.reset();
91 is_shutdown_ = true;
92 }
93
SetDataFetcherForTests(DataFetcherSharedMemory * test_data_fetcher)94 void DeviceInertialSensorService::SetDataFetcherForTests(
95 DataFetcherSharedMemory* test_data_fetcher) {
96 data_fetcher_.reset(test_data_fetcher);
97 }
98
99 } // namespace content
100