1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
// Copyright 2015 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/metronome_client.h"
#include "base/bind.h"
#include "base/rand_util.h"
#include "base/command_line.h"
#include "base/logging.h"
#include "base/memory/weak_ptr.h"
#include "base/observer_list.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "chromeos/chromeos_switches.h"
#include "dbus/bus.h"
#include "dbus/message.h"
#include "dbus/object_path.h"
#include "dbus/object_proxy.h"
// TODO(benchan): Move these DBus constants to system_api.
namespace metronome {
const char kMetronomeInterface[] = "org.chromium.Metronome";
const char kMetronomeServiceName[] = "org.chromium.Metronome";
const char kMetronomeServicePath[] = "/org/chromium/Metronome";
const char kTimestampUpdatedSignal[] = "TimestampUpdated";
} // namespace metronome
namespace chromeos {
namespace {
////////////////////////////////////////////////////////////////////////////////
// The MetronomeClient implementation.
class MetronomeClientImpl : public MetronomeClient {
public:
MetronomeClientImpl()
: proxy_(nullptr), signal_connected_(false), weak_ptr_factory_(this) {}
~MetronomeClientImpl() override {}
// MetronomeClient:
void AddObserver(Observer* observer) override;
void RemoveObserver(Observer* observer) override;
protected:
// DBusClient:
void Init(dbus::Bus* bus) override;
private:
// Handles TimestampUpdated signal and notifies |observers_|.
void OnTimestampUpdated(dbus::Signal* signal);
// Handles the result of signal connection setup.
void OnSignalConnected(const std::string& interface,
const std::string& signal,
bool succeeded);
dbus::ObjectProxy* proxy_;
// True when |proxy_| has been connected.
bool signal_connected_;
// List of observers interested in event notifications from us.
ObserverList<Observer> observers_;
// Note: This should remain the last member so it'll be destroyed and
// invalidate its weak pointers before any other members are destroyed.
base::WeakPtrFactory<MetronomeClientImpl> weak_ptr_factory_;
DISALLOW_COPY_AND_ASSIGN(MetronomeClientImpl);
};
void MetronomeClientImpl::AddObserver(Observer* observer) {
DCHECK(observer);
if (!signal_connected_) {
signal_connected_ = true;
proxy_->ConnectToSignal(metronome::kMetronomeInterface,
metronome::kTimestampUpdatedSignal,
base::Bind(&MetronomeClientImpl::OnTimestampUpdated,
weak_ptr_factory_.GetWeakPtr()),
base::Bind(&MetronomeClientImpl::OnSignalConnected,
weak_ptr_factory_.GetWeakPtr()));
}
observers_.AddObserver(observer);
}
void MetronomeClientImpl::RemoveObserver(Observer* observer) {
DCHECK(observer);
observers_.RemoveObserver(observer);
}
void MetronomeClientImpl::Init(dbus::Bus* bus) {
proxy_ =
bus->GetObjectProxy(metronome::kMetronomeServiceName,
dbus::ObjectPath(metronome::kMetronomeServicePath));
}
void MetronomeClientImpl::OnTimestampUpdated(dbus::Signal* signal) {
dbus::MessageReader reader(signal);
uint64 beacon_timestamp = 0;
uint64 local_timestamp = 0;
if (!reader.PopUint64(&beacon_timestamp) ||
!reader.PopUint64(&local_timestamp)) {
LOG(ERROR) << "Invalid signal: " << signal->ToString();
return;
}
FOR_EACH_OBSERVER(Observer, observers_,
OnTimestampUpdated(beacon_timestamp, local_timestamp));
}
void MetronomeClientImpl::OnSignalConnected(const std::string& interface,
const std::string& signal,
bool succeeded) {
LOG_IF(ERROR, !succeeded) << "Connect to " << interface << " " << signal
<< " failed.";
}
////////////////////////////////////////////////////////////////////////////////
// A fake implementation of MetronomeClient. It does not provide true
// synchronization and only exists to exercise the interfaces.
class MetronomeClientFakeImpl : public MetronomeClient {
public:
MetronomeClientFakeImpl()
: random_offset_(base::RandInt(-1000000, 1000000)) {}
~MetronomeClientFakeImpl() override { beacon_timer_.Stop(); }
// MetronomeClient:
void AddObserver(Observer* observer) override {
DCHECK(observer);
observers_.AddObserver(observer);
}
void RemoveObserver(Observer* observer) override {
DCHECK(observer);
observers_.RemoveObserver(observer);
}
// DBusClient:
void Init(dbus::Bus* bus) override {
beacon_timer_.Start(FROM_HERE,
base::TimeDelta::FromMilliseconds(1000),
this,
&MetronomeClientFakeImpl::UpdateBeacon);
}
private:
void UpdateBeacon() {
base::Time now_time = base::Time::Now();
base::TimeTicks now_ticks = base::TimeTicks::Now();
uint64 fake_beacon_timestamp = now_time.ToInternalValue() +
base::RandInt(-1000, 1000);
uint64 fake_local_timestamp = now_ticks.ToInternalValue() + random_offset_ +
base::RandInt(-1000, 1000);
FOR_EACH_OBSERVER(
Observer, observers_,
OnTimestampUpdated(fake_beacon_timestamp, fake_local_timestamp));
}
int64 random_offset_;
base::RepeatingTimer<MetronomeClientFakeImpl> beacon_timer_;
// List of observers interested in event notifications from us.
ObserverList<Observer> observers_;
DISALLOW_COPY_AND_ASSIGN(MetronomeClientFakeImpl);
};
////////////////////////////////////////////////////////////////////////////////
// A stub implementation of MetronomeClient. It allows unit tests to complete.
class MetronomeClientStubImpl : public MetronomeClient {
public:
MetronomeClientStubImpl() {}
~MetronomeClientStubImpl() override {}
// MetronomeClient:
void AddObserver(Observer* observer) override {}
void RemoveObserver(Observer* observer) override {}
// DBusClient:
void Init(dbus::Bus* bus) override {}
private:
DISALLOW_COPY_AND_ASSIGN(MetronomeClientStubImpl);
};
} // namespace
////////////////////////////////////////////////////////////////////////////////
MetronomeClient::MetronomeClient() {
}
MetronomeClient::~MetronomeClient() {
}
// static
MetronomeClient* MetronomeClient::Create(DBusClientImplementationType type) {
if (type == REAL_DBUS_CLIENT_IMPLEMENTATION)
return new MetronomeClientImpl();
DCHECK_EQ(STUB_DBUS_CLIENT_IMPLEMENTATION, type);
if (base::CommandLine::ForCurrentProcess()->HasSwitch(
switches::kTestMetronomeTimer)) {
return new MetronomeClientFakeImpl();
}
return new MetronomeClientStubImpl();
}
} // namespace chromeos
|
