blob: c19cdf4778b289b9c994261ceb5dfc4d63a42585 [file] [log] [blame]
// Copyright 2016 The Chromium Authors
// 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 "third_party/abseil-cpp/absl/base/attributes.h"
namespace base {
namespace {
base::AtomicSequenceNumber g_sequence_token_generator;
base::AtomicSequenceNumber g_task_token_generator;
ABSL_CONST_INIT thread_local SequenceToken current_sequence_token;
ABSL_CONST_INIT thread_local TaskToken current_task_token;
} // 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() {
return current_sequence_token;
}
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() {
return current_task_token;
}
ScopedSetSequenceTokenForCurrentThread::ScopedSetSequenceTokenForCurrentThread(
const SequenceToken& sequence_token)
// The lambdas here exist because invalid tokens don't compare equal, so
// passing invalid sequence/task tokens as the third args to AutoReset
// constructors doesn't work.
: sequence_token_resetter_(&current_sequence_token,
[&sequence_token]() {
DCHECK(!current_sequence_token.IsValid());
return sequence_token;
}()),
task_token_resetter_(&current_task_token, [] {
DCHECK(!current_task_token.IsValid());
return TaskToken::Create();
}()) {}
ScopedSetSequenceTokenForCurrentThread::
~ScopedSetSequenceTokenForCurrentThread() = default;
} // namespace base