From aba9219e5c74e1841932bc15e38e4c83f99f23ee Mon Sep 17 00:00:00 2001
From: "tommi@webrtc.org" <tommi@webrtc.org>
Date: Mon, 16 Mar 2015 16:05:50 +0000
Subject: [PATCH] Change ThreadPosix to use an auto-reset event instead of
 manual reset now that we know the problem we had with EventWrapper::Wait was
 simply a bug in the EventWrapper.  Also removing |started_| since we can just
 check the thread_ instead.

R=pbos@webrtc.org
BUG=4413

Review URL: https://webrtc-codereview.appspot.com/47539004

Cr-Commit-Position: refs/heads/master@{#8738}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8738 4adac7df-926f-26a2-2b94-8c16560cd09d
---
 webrtc/system_wrappers/source/thread_posix.cc | 12 +++++-------
 webrtc/system_wrappers/source/thread_posix.h  |  1 -
 webrtc/video_engine/vie_capturer.cc           |  4 +---
 webrtc/video_engine/vie_channel.cc            | 19 ++++---------------
 4 files changed, 10 insertions(+), 26 deletions(-)

diff --git a/webrtc/system_wrappers/source/thread_posix.cc b/webrtc/system_wrappers/source/thread_posix.cc
index 84ed52d168..bbf3b982e7 100644
--- a/webrtc/system_wrappers/source/thread_posix.cc
+++ b/webrtc/system_wrappers/source/thread_posix.cc
@@ -62,6 +62,7 @@ int ConvertToSystemPriority(ThreadPriority priority, int min_prio,
   return low_prio;
 }
 
+// static
 void* ThreadPosix::StartThread(void* param) {
   static_cast<ThreadPosix*>(param)->Run();
   return 0;
@@ -72,8 +73,7 @@ ThreadPosix::ThreadPosix(ThreadRunFunction func, ThreadObj obj,
     : run_function_(func),
       obj_(obj),
       prio_(prio),
-      started_(false),
-      stop_event_(true, false),
+      stop_event_(false, false),
       name_(thread_name ? thread_name : "webrtc"),
       thread_(0) {
   DCHECK(name_.length() < kThreadMaxNameLength);
@@ -91,25 +91,23 @@ ThreadPosix::~ThreadPosix() {
 // here.
 bool ThreadPosix::Start() {
   DCHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(!thread_) << "Thread already started?";
 
   ThreadAttributes attr;
   // Set the stack stack size to 1M.
   pthread_attr_setstacksize(&attr, 1024 * 1024);
-
   CHECK_EQ(0, pthread_create(&thread_, &attr, &StartThread, this));
-  started_ = true;
   return true;
 }
 
 bool ThreadPosix::Stop() {
   DCHECK(thread_checker_.CalledOnValidThread());
-  if (!started_)
+  if (!thread_)
     return true;
 
   stop_event_.Set();
   CHECK_EQ(0, pthread_join(thread_, nullptr));
-  started_ = false;
-  stop_event_.Reset();
+  thread_ = 0;
 
   return true;
 }
diff --git a/webrtc/system_wrappers/source/thread_posix.h b/webrtc/system_wrappers/source/thread_posix.h
index c1cf8b5815..746984ffbf 100644
--- a/webrtc/system_wrappers/source/thread_posix.h
+++ b/webrtc/system_wrappers/source/thread_posix.h
@@ -42,7 +42,6 @@ class ThreadPosix : public ThreadWrapper {
   ThreadRunFunction const run_function_;
   void* const obj_;
   ThreadPriority prio_;
-  bool started_;
   rtc::Event stop_event_;
   const std::string name_;
 
diff --git a/webrtc/video_engine/vie_capturer.cc b/webrtc/video_engine/vie_capturer.cc
index 379ae2ab61..867369c1d8 100644
--- a/webrtc/video_engine/vie_capturer.cc
+++ b/webrtc/video_engine/vie_capturer.cc
@@ -88,9 +88,7 @@ ViECapturer::ViECapturer(int capture_id,
       overuse_detector_(
           new OveruseFrameDetector(Clock::GetRealTimeClock(),
                                    cpu_overuse_metrics_observer_.get())) {
-  if (!capture_thread_.Start()) {
-    assert(false);
-  }
+  capture_thread_.Start();
   module_process_thread_.RegisterModule(overuse_detector_.get());
 }
 
diff --git a/webrtc/video_engine/vie_channel.cc b/webrtc/video_engine/vie_channel.cc
index bbf5d535ad..d1bcf74fff 100644
--- a/webrtc/video_engine/vie_channel.cc
+++ b/webrtc/video_engine/vie_channel.cc
@@ -1842,16 +1842,7 @@ int32_t ViEChannel::StartDecodeThread() {
   decode_thread_ = ThreadWrapper::CreateThread(ChannelDecodeThreadFunction,
                                                    this, kHighestPriority,
                                                    "DecodingThread");
-  if (!decode_thread_) {
-    return -1;
-  }
-
-  if (decode_thread_->Start() == false) {
-    delete decode_thread_;
-    decode_thread_ = NULL;
-    LOG(LS_ERROR) << "Could not start decode thread.";
-    return -1;
-  }
+  decode_thread_->Start();
   return 0;
 }
 
@@ -1862,12 +1853,10 @@ int32_t ViEChannel::StopDecodeThread() {
 
   vcm_->TriggerDecoderShutdown();
 
-  if (decode_thread_->Stop()) {
-    delete decode_thread_;
-  } else {
-    assert(false && "could not stop decode thread");
-  }
+  decode_thread_->Stop();
+  delete decode_thread_;
   decode_thread_ = NULL;
+
   return 0;
 }