naiveproxy/base/threading/thread_checker_impl.cc
2018-01-28 13:32:06 -05:00

58 lines
1.7 KiB
C++

// Copyright (c) 2011 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/threading/thread_checker_impl.h"
#include "base/threading/thread_task_runner_handle.h"
namespace base {
ThreadCheckerImpl::ThreadCheckerImpl() {
AutoLock auto_lock(lock_);
EnsureAssigned();
}
ThreadCheckerImpl::~ThreadCheckerImpl() = default;
bool ThreadCheckerImpl::CalledOnValidThread() const {
AutoLock auto_lock(lock_);
EnsureAssigned();
// Always return true when called from the task from which this
// ThreadCheckerImpl was assigned to a thread.
if (task_token_ == TaskToken::GetForCurrentThread())
return true;
// If this ThreadCheckerImpl is bound to a valid SequenceToken, it must be
// equal to the current SequenceToken and there must be a registered
// ThreadTaskRunnerHandle. Otherwise, the fact that the current task runs on
// the thread to which this ThreadCheckerImpl is bound is fortuitous.
if (sequence_token_.IsValid() &&
(sequence_token_ != SequenceToken::GetForCurrentThread() ||
!ThreadTaskRunnerHandle::IsSet())) {
return false;
}
return thread_id_ == PlatformThread::CurrentRef();
}
void ThreadCheckerImpl::DetachFromThread() {
AutoLock auto_lock(lock_);
thread_id_ = PlatformThreadRef();
task_token_ = TaskToken();
sequence_token_ = SequenceToken();
}
void ThreadCheckerImpl::EnsureAssigned() const {
lock_.AssertAcquired();
if (!thread_id_.is_null())
return;
thread_id_ = PlatformThread::CurrentRef();
task_token_ = TaskToken::GetForCurrentThread();
sequence_token_ = SequenceToken::GetForCurrentThread();
}
} // namespace base