Index: base/threading/thread.cc |
diff --git a/base/threading/thread.cc b/base/threading/thread.cc |
index 98610a63c09875878ffceca6417d7af16980ca89..f73113a6353929ab42ebd1d5d3e50acc33f001d4 100644 |
--- a/base/threading/thread.cc |
+++ b/base/threading/thread.cc |
@@ -8,6 +8,7 @@ |
#include "base/bind_helpers.h" |
#include "base/lazy_instance.h" |
#include "base/location.h" |
+#include "base/logging.h" |
#include "base/run_loop.h" |
#include "base/synchronization/waitable_event.h" |
#include "base/third_party/dynamic_annotations/dynamic_annotations.h" |
@@ -28,7 +29,7 @@ namespace { |
// because its Stop method was called. This allows us to catch cases where |
// MessageLoop::QuitWhenIdle() is called directly, which is unexpected when |
// using a Thread to setup and run a MessageLoop. |
-base::LazyInstance<base::ThreadLocalBoolean> lazy_tls_bool = |
+base::LazyInstance<base::ThreadLocalBoolean>::Leaky lazy_tls_bool = |
LAZY_INSTANCE_INITIALIZER; |
} // namespace |
@@ -57,6 +58,10 @@ Thread::Thread(const std::string& name) |
Thread::~Thread() { |
Stop(); |
+ |
+ // ThreadMain() must have returned before this Thread instance is destroyed |
+ // or use-after-frees could ensue. |
+ DCHECK(!thread_main_exited_.get() || thread_main_exited_->IsSet()); |
danakj
2016/07/28 19:07:40
no .get()
gab
2016/07/28 21:40:15
I intentionally added the .get()'s here and below
|
} |
bool Thread::Start() { |
@@ -74,6 +79,8 @@ bool Thread::StartWithOptions(const Options& options) { |
DCHECK(owning_sequence_checker_.CalledOnValidSequencedThread()); |
DCHECK(!message_loop_); |
DCHECK(!IsRunning()); |
+ DCHECK(!stopping_) << "Starting a non-joinable thread a second time? That's " |
+ << "not allowed!"; |
#if defined(OS_WIN) |
DCHECK((com_status_ != STA) || |
(options.message_loop_type == MessageLoop::TYPE_UI)); |
@@ -83,6 +90,14 @@ bool Thread::StartWithOptions(const Options& options) { |
id_event_.Reset(); |
id_ = kInvalidThreadId; |
+ if (!thread_main_exited_.get()) { |
danakj
2016/07/28 19:07:40
no .get()
gab
2016/07/28 21:40:15
Similarly here:
if (!thread_main_exited_)
feels
|
+ thread_main_exited_.reset(new AtomicFlag); |
+ } else { |
+ // It's safe to reset |thread_main_exited_| on sequence when the underlying |
+ // thread isn't running. |
+ thread_main_exited_->UnsafeReset(); |
+ } |
+ |
SetThreadWasQuitProperly(false); |
MessageLoop::Type type = options.message_loop_type; |
@@ -100,8 +115,13 @@ bool Thread::StartWithOptions(const Options& options) { |
// fixed). |
{ |
AutoLock lock(thread_lock_); |
- if (!PlatformThread::CreateWithPriority(options.stack_size, this, &thread_, |
- options.priority)) { |
+ bool success = |
+ options.joinable |
+ ? PlatformThread::CreateWithPriority(options.stack_size, this, |
+ &thread_, options.priority) |
+ : PlatformThread::CreateNonJoinableWithPriority( |
+ options.stack_size, this, options.priority); |
+ if (!success) { |
DLOG(ERROR) << "failed to create thread"; |
message_loop_ = nullptr; |
return false; |
@@ -141,11 +161,12 @@ void Thread::Stop() { |
// DCHECK(owning_sequence_checker_.CalledOnValidSequencedThread()); |
AutoLock lock(thread_lock_); |
+ StopSoon(); |
+ |
+ // Can't join if the |thread_| is either already gone or is non-joinable. |
if (thread_.is_null()) |
return; |
- StopSoon(); |
- |
// Wait for the thread to exit. |
// |
// TODO(darin): Unfortunately, we need to keep |message_loop_| around until |
@@ -170,6 +191,16 @@ void Thread::StopSoon() { |
return; |
stopping_ = true; |
+ |
+ if (using_external_message_loop_) { |
+ // Setting |stopping_| to true above should have been sufficient for this |
+ // thread to be considered "stopped" per it having never set its |running_| |
+ // bit by lack of its own ThreadMain. |
+ DCHECK(!IsRunning()); |
+ message_loop_ = nullptr; |
+ return; |
+ } |
+ |
task_runner()->PostTask( |
FROM_HERE, base::Bind(&Thread::ThreadQuitHelper, Unretained(this))); |
} |
@@ -219,6 +250,18 @@ bool Thread::GetThreadWasQuitProperly() { |
return quit_properly; |
} |
+void Thread::SetMessageLoop(MessageLoop* message_loop) { |
+ DCHECK(owning_sequence_checker_.CalledOnValidSequencedThread()); |
+ |
+ // Setting |message_loop_| should suffice for this thread to be considered |
+ // as "running", until Stop() is invoked. |
+ DCHECK(!IsRunning()); |
+ message_loop_ = message_loop; |
+ DCHECK(IsRunning()); |
+ |
+ using_external_message_loop_ = true; |
+} |
+ |
void Thread::ThreadMain() { |
// First, make GetThreadId() available to avoid deadlocks. It could be called |
// any place in the following thread initialization code. |
@@ -282,6 +325,8 @@ void Thread::ThreadMain() { |
// (The message loop is destructed at the end of this block) |
message_loop_ = nullptr; |
run_loop_ = nullptr; |
+ |
+ thread_main_exited_->Set(); |
} |
void Thread::ThreadQuitHelper() { |