deadbeef | 8290ddf | 2017-07-11 16:56:05 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| 3 | * |
| 4 | * Use of this source code is governed by a BSD-style license |
| 5 | * that can be found in the LICENSE file in the root of the source |
| 6 | * tree. An additional intellectual property rights grant can be found |
| 7 | * in the file PATENTS. All contributing project authors may |
| 8 | * be found in the AUTHORS file in the root of the source tree. |
| 9 | */ |
| 10 | |
Mirko Bonadei | 92ea95e | 2017-09-15 06:47:31 +0200 | [diff] [blame^] | 11 | #include "rtc_base/signalthread.h" |
deadbeef | 8290ddf | 2017-07-11 16:56:05 -0700 | [diff] [blame] | 12 | |
Mirko Bonadei | 92ea95e | 2017-09-15 06:47:31 +0200 | [diff] [blame^] | 13 | #include "rtc_base/checks.h" |
deadbeef | 8290ddf | 2017-07-11 16:56:05 -0700 | [diff] [blame] | 14 | |
| 15 | namespace rtc { |
| 16 | |
| 17 | /////////////////////////////////////////////////////////////////////////////// |
| 18 | // SignalThread |
| 19 | /////////////////////////////////////////////////////////////////////////////// |
| 20 | |
| 21 | SignalThread::SignalThread(bool use_socket_server) |
| 22 | : main_(Thread::Current()), |
| 23 | worker_(this, use_socket_server), |
| 24 | state_(kInit), |
| 25 | refcount_(1) { |
| 26 | main_->SignalQueueDestroyed.connect(this, |
| 27 | &SignalThread::OnMainThreadDestroyed); |
| 28 | worker_.SetName("SignalThread", this); |
| 29 | } |
| 30 | |
| 31 | SignalThread::~SignalThread() { |
| 32 | RTC_DCHECK(refcount_ == 0); |
| 33 | } |
| 34 | |
| 35 | bool SignalThread::SetName(const std::string& name, const void* obj) { |
| 36 | EnterExit ee(this); |
| 37 | RTC_DCHECK(main_->IsCurrent()); |
| 38 | RTC_DCHECK(kInit == state_); |
| 39 | return worker_.SetName(name, obj); |
| 40 | } |
| 41 | |
| 42 | void SignalThread::Start() { |
| 43 | EnterExit ee(this); |
| 44 | RTC_DCHECK(main_->IsCurrent()); |
| 45 | if (kInit == state_ || kComplete == state_) { |
| 46 | state_ = kRunning; |
| 47 | OnWorkStart(); |
| 48 | worker_.Start(); |
| 49 | } else { |
| 50 | RTC_NOTREACHED(); |
| 51 | } |
| 52 | } |
| 53 | |
| 54 | void SignalThread::Destroy(bool wait) { |
| 55 | EnterExit ee(this); |
| 56 | RTC_DCHECK(main_->IsCurrent()); |
| 57 | if ((kInit == state_) || (kComplete == state_)) { |
| 58 | refcount_--; |
| 59 | } else if (kRunning == state_ || kReleasing == state_) { |
| 60 | state_ = kStopping; |
| 61 | // OnWorkStop() must follow Quit(), so that when the thread wakes up due to |
| 62 | // OWS(), ContinueWork() will return false. |
| 63 | worker_.Quit(); |
| 64 | OnWorkStop(); |
| 65 | if (wait) { |
| 66 | // Release the thread's lock so that it can return from ::Run. |
| 67 | cs_.Leave(); |
| 68 | worker_.Stop(); |
| 69 | cs_.Enter(); |
| 70 | refcount_--; |
| 71 | } |
| 72 | } else { |
| 73 | RTC_NOTREACHED(); |
| 74 | } |
| 75 | } |
| 76 | |
| 77 | void SignalThread::Release() { |
| 78 | EnterExit ee(this); |
| 79 | RTC_DCHECK(main_->IsCurrent()); |
| 80 | if (kComplete == state_) { |
| 81 | refcount_--; |
| 82 | } else if (kRunning == state_) { |
| 83 | state_ = kReleasing; |
| 84 | } else { |
| 85 | // if (kInit == state_) use Destroy() |
| 86 | RTC_NOTREACHED(); |
| 87 | } |
| 88 | } |
| 89 | |
| 90 | bool SignalThread::ContinueWork() { |
| 91 | EnterExit ee(this); |
| 92 | RTC_DCHECK(worker_.IsCurrent()); |
| 93 | return worker_.ProcessMessages(0); |
| 94 | } |
| 95 | |
| 96 | void SignalThread::OnMessage(Message *msg) { |
| 97 | EnterExit ee(this); |
| 98 | if (ST_MSG_WORKER_DONE == msg->message_id) { |
| 99 | RTC_DCHECK(main_->IsCurrent()); |
| 100 | OnWorkDone(); |
| 101 | bool do_delete = false; |
| 102 | if (kRunning == state_) { |
| 103 | state_ = kComplete; |
| 104 | } else { |
| 105 | do_delete = true; |
| 106 | } |
| 107 | if (kStopping != state_) { |
| 108 | // Before signaling that the work is done, make sure that the worker |
| 109 | // thread actually is done. We got here because DoWork() finished and |
| 110 | // Run() posted the ST_MSG_WORKER_DONE message. This means the worker |
| 111 | // thread is about to go away anyway, but sometimes it doesn't actually |
| 112 | // finish before SignalWorkDone is processed, and for a reusable |
| 113 | // SignalThread this makes an assert in thread.cc fire. |
| 114 | // |
| 115 | // Calling Stop() on the worker ensures that the OS thread that underlies |
| 116 | // the worker will finish, and will be set to null, enabling us to call |
| 117 | // Start() again. |
| 118 | worker_.Stop(); |
| 119 | SignalWorkDone(this); |
| 120 | } |
| 121 | if (do_delete) { |
| 122 | refcount_--; |
| 123 | } |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | SignalThread::Worker::~Worker() { |
| 128 | Stop(); |
| 129 | } |
| 130 | |
| 131 | void SignalThread::Worker::Run() { |
| 132 | parent_->Run(); |
| 133 | } |
| 134 | |
| 135 | void SignalThread::Run() { |
| 136 | DoWork(); |
| 137 | { |
| 138 | EnterExit ee(this); |
| 139 | if (main_) { |
| 140 | main_->Post(RTC_FROM_HERE, this, ST_MSG_WORKER_DONE); |
| 141 | } |
| 142 | } |
| 143 | } |
| 144 | |
| 145 | void SignalThread::OnMainThreadDestroyed() { |
| 146 | EnterExit ee(this); |
| 147 | main_ = nullptr; |
| 148 | } |
| 149 | |
| 150 | bool SignalThread::Worker::IsProcessingMessages() { |
| 151 | return false; |
| 152 | } |
| 153 | |
| 154 | } // namespace rtc |