blob: 1fa75e9f7daa1c191129aedee38c9803176ba7a1 (
plain)
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
|
// Copyright (c) 2012 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 "chrome/common/worker_thread_ticker.h"
#include <algorithm>
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/logging.h"
#include "base/message_loop/message_loop.h"
#include "base/threading/thread.h"
WorkerThreadTicker::WorkerThreadTicker(int tick_interval)
: timer_thread_("worker_thread_ticker"),
is_running_(false),
tick_interval_(base::TimeDelta::FromMilliseconds(tick_interval)) {
}
WorkerThreadTicker::~WorkerThreadTicker() {
Stop();
}
bool WorkerThreadTicker::RegisterTickHandler(Callback *tick_handler) {
DCHECK(tick_handler);
base::AutoLock lock(lock_);
// You cannot change the list of handlers when the timer is running.
// You need to call Stop first.
if (IsRunning())
return false;
tick_handler_list_.push_back(tick_handler);
return true;
}
bool WorkerThreadTicker::UnregisterTickHandler(Callback *tick_handler) {
DCHECK(tick_handler);
base::AutoLock lock(lock_);
// You cannot change the list of handlers when the timer is running.
// You need to call Stop first.
if (IsRunning()) {
return false;
}
TickHandlerListType::iterator index = std::remove(tick_handler_list_.begin(),
tick_handler_list_.end(),
tick_handler);
if (index == tick_handler_list_.end()) {
return false;
}
tick_handler_list_.erase(index, tick_handler_list_.end());
return true;
}
bool WorkerThreadTicker::Start() {
// Do this in a lock because we don't want 2 threads to
// call Start at the same time
base::AutoLock lock(lock_);
if (IsRunning())
return false;
if (!timer_thread_.Start())
return false;
is_running_ = true;
ScheduleTimerTask();
return true;
}
bool WorkerThreadTicker::Stop() {
// Do this in a lock because we don't want 2 threads to
// call Stop at the same time
base::AutoLock lock(lock_);
if (!IsRunning())
return false;
is_running_ = false;
timer_thread_.Stop();
return true;
}
void WorkerThreadTicker::ScheduleTimerTask() {
timer_thread_.message_loop()->PostDelayedTask(
FROM_HERE,
base::Bind(&WorkerThreadTicker::TimerTask, base::Unretained(this)),
tick_interval_);
}
void WorkerThreadTicker::TimerTask() {
// When the ticker is running, the handler list CANNOT be modified.
// So we can do the enumeration safely without a lock
const TickHandlerListType& handlers = tick_handler_list_;
for (TickHandlerListType::const_iterator i = handlers.begin();
i != handlers.end(); ++i) {
(*i)->OnTick();
}
ScheduleTimerTask();
}
|
