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
|
/*
* libjingle
* Copyright 2004--2009, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "talk/base/signalthread.h"
#include "talk/base/common.h"
namespace talk_base {
///////////////////////////////////////////////////////////////////////////////
// SignalThread
///////////////////////////////////////////////////////////////////////////////
SignalThread::SignalThread()
: main_(Thread::Current()),
worker_(this),
state_(kInit),
refcount_(1) {
main_->SignalQueueDestroyed.connect(this,
&SignalThread::OnMainThreadDestroyed);
worker_.SetName("SignalThread", this);
}
SignalThread::~SignalThread() {
ASSERT(refcount_ == 0);
}
bool SignalThread::SetName(const std::string& name, const void* obj) {
EnterExit ee(this);
ASSERT(main_->IsCurrent());
ASSERT(kInit == state_);
return worker_.SetName(name, obj);
}
bool SignalThread::SetPriority(ThreadPriority priority) {
EnterExit ee(this);
ASSERT(main_->IsCurrent());
ASSERT(kInit == state_);
return worker_.SetPriority(priority);
}
void SignalThread::Start() {
EnterExit ee(this);
ASSERT(main_->IsCurrent());
if (kInit == state_ || kComplete == state_) {
state_ = kRunning;
OnWorkStart();
worker_.Start();
} else {
ASSERT(false);
}
}
void SignalThread::Destroy(bool wait) {
EnterExit ee(this);
ASSERT(main_->IsCurrent());
if ((kInit == state_) || (kComplete == state_)) {
refcount_--;
} else if (kRunning == state_ || kReleasing == state_) {
state_ = kStopping;
// OnWorkStop() must follow Quit(), so that when the thread wakes up due to
// OWS(), ContinueWork() will return false.
worker_.Quit();
OnWorkStop();
if (wait) {
// Release the thread's lock so that it can return from ::Run.
cs_.Leave();
worker_.Stop();
cs_.Enter();
refcount_--;
}
} else {
ASSERT(false);
}
}
void SignalThread::Release() {
EnterExit ee(this);
ASSERT(main_->IsCurrent());
if (kComplete == state_) {
refcount_--;
} else if (kRunning == state_) {
state_ = kReleasing;
} else {
// if (kInit == state_) use Destroy()
ASSERT(false);
}
}
bool SignalThread::ContinueWork() {
EnterExit ee(this);
ASSERT(worker_.IsCurrent());
return worker_.ProcessMessages(0);
}
void SignalThread::OnMessage(Message *msg) {
EnterExit ee(this);
if (ST_MSG_WORKER_DONE == msg->message_id) {
ASSERT(main_->IsCurrent());
OnWorkDone();
bool do_delete = false;
if (kRunning == state_) {
state_ = kComplete;
} else {
do_delete = true;
}
if (kStopping != state_) {
// Before signaling that the work is done, make sure that the worker
// thread actually is done. We got here because DoWork() finished and
// Run() posted the ST_MSG_WORKER_DONE message. This means the worker
// thread is about to go away anyway, but sometimes it doesn't actually
// finish before SignalWorkDone is processed, and for a reusable
// SignalThread this makes an assert in thread.cc fire.
//
// Calling Stop() on the worker ensures that the OS thread that underlies
// the worker will finish, and will be set to NULL, enabling us to call
// Start() again.
worker_.Stop();
SignalWorkDone(this);
}
if (do_delete) {
refcount_--;
}
}
}
void SignalThread::Run() {
DoWork();
{
EnterExit ee(this);
if (main_) {
main_->Post(this, ST_MSG_WORKER_DONE);
}
}
}
void SignalThread::OnMainThreadDestroyed() {
EnterExit ee(this);
main_ = NULL;
}
} // namespace talk_base
|
