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/*
* Copyright 2004 The WebRTC Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/base/signalthread.h"
#include "webrtc/base/common.h"
namespace rtc {
///////////////////////////////////////////////////////////////////////////////
// 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_--;
}
}
}
SignalThread::Worker::~Worker() {
Stop();
}
void SignalThread::Worker::Run() {
parent_->Run();
}
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 rtc
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