// Copyright 2016 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/sequence_token.h" #include "base/atomic_sequence_num.h" #include "base/check_op.h" #include "base/no_destructor.h" #include "base/threading/thread_local.h" namespace base { namespace { base::AtomicSequenceNumber g_sequence_token_generator; base::AtomicSequenceNumber g_task_token_generator; ThreadLocalPointer& GetTlsCurrentSequenceToken() { static base::NoDestructor> instance; return *instance; } ThreadLocalPointer& GetTlsCurrentTaskToken() { static base::NoDestructor> instance; return *instance; } } // namespace bool SequenceToken::operator==(const SequenceToken& other) const { return token_ == other.token_ && IsValid(); } bool SequenceToken::operator!=(const SequenceToken& other) const { return !(*this == other); } bool SequenceToken::IsValid() const { return token_ != kInvalidSequenceToken; } int SequenceToken::ToInternalValue() const { return token_; } SequenceToken SequenceToken::Create() { return SequenceToken(g_sequence_token_generator.GetNext()); } SequenceToken SequenceToken::GetForCurrentThread() { const SequenceToken* current_sequence_token = GetTlsCurrentSequenceToken().Get(); return current_sequence_token ? *current_sequence_token : SequenceToken(); } bool TaskToken::operator==(const TaskToken& other) const { return token_ == other.token_ && IsValid(); } bool TaskToken::operator!=(const TaskToken& other) const { return !(*this == other); } bool TaskToken::IsValid() const { return token_ != kInvalidTaskToken; } TaskToken TaskToken::Create() { return TaskToken(g_task_token_generator.GetNext()); } TaskToken TaskToken::GetForCurrentThread() { const TaskToken* current_task_token = GetTlsCurrentTaskToken().Get(); return current_task_token ? *current_task_token : TaskToken(); } ScopedSetSequenceTokenForCurrentThread::ScopedSetSequenceTokenForCurrentThread( const SequenceToken& sequence_token) : sequence_token_(sequence_token), task_token_(TaskToken::Create()) { DCHECK(!GetTlsCurrentSequenceToken().Get()); DCHECK(!GetTlsCurrentTaskToken().Get()); GetTlsCurrentSequenceToken().Set(&sequence_token_); GetTlsCurrentTaskToken().Set(&task_token_); } ScopedSetSequenceTokenForCurrentThread:: ~ScopedSetSequenceTokenForCurrentThread() { DCHECK_EQ(GetTlsCurrentSequenceToken().Get(), &sequence_token_); DCHECK_EQ(GetTlsCurrentTaskToken().Get(), &task_token_); GetTlsCurrentSequenceToken().Set(nullptr); GetTlsCurrentTaskToken().Set(nullptr); } } // namespace base