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base / sequence_token.cc [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"
namespace base {
namespace internal {
namespace {
base::AtomicSequenceNumber g_sequence_token_generator;
base::AtomicSequenceNumber g_task_token_generator;
constinit thread_local SequenceToken current_sequence_token;
constinit thread_local TaskToken current_task_token;
constinit thread_local bool current_task_is_thread_bound = true;
constinit thread_local bool current_task_is_running_synchronously = false;
} // 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() {
if (!current_sequence_token.IsValid()) {
current_sequence_token = SequenceToken::Create();
DCHECK(current_task_is_thread_bound);
}
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;
}
bool CurrentTaskIsThreadBound() {
return current_task_is_thread_bound;
}
TaskScope::TaskScope(SequenceToken sequence_token,
bool is_single_threaded,
bool is_running_synchronously)
: previous_task_token_(TaskToken::GetForCurrentThread()),
previous_sequence_token_(SequenceToken::GetForCurrentThread()),
previous_task_is_thread_bound_(current_task_is_thread_bound),
previous_task_is_running_synchronously_(
current_task_is_running_synchronously) {
current_task_token = TaskToken::Create();
current_sequence_token = sequence_token;
current_task_is_thread_bound = is_single_threaded;
current_task_is_running_synchronously = is_running_synchronously;
}
TaskScope::~TaskScope() {
current_task_token = previous_task_token_;
current_sequence_token = previous_sequence_token_;
current_task_is_thread_bound = previous_task_is_thread_bound_;
current_task_is_running_synchronously =
previous_task_is_running_synchronously_;
}
} // namespace internal
bool CurrentTaskIsRunningSynchronously() {
return internal::current_task_is_running_synchronously;
}
} // namespace base