blob: 05894ab182c444e1dda5a57a44a3fe230428584c [file] [log] [blame]
// Copyright (c) 2012 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 <memory>
#include <utility>
#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/callback.h"
#include "base/callback_helpers.h"
#include "base/logging.h"
#include "base/post_task_and_reply_with_result_internal.h"
#include "base/task_runner.h"
namespace base {
// When you have these methods
// R DoWorkAndReturn();
// void Callback(const R& result);
// and want to call them in a PostTaskAndReply kind of fashion where the
// result of DoWorkAndReturn is passed to the Callback, you can use
// PostTaskAndReplyWithResult as in this example:
// PostTaskAndReplyWithResult(
// target_thread_.task_runner(),
// BindOnce(&DoWorkAndReturn),
// BindOnce(&Callback));
// Though RepeatingCallback is convertible to OnceCallback, we need a
// CallbackType template since we can not use template deduction and object
// conversion at once on the overload resolution.
// TODO( Update all callers of the RepeatingCallback version
// to use OnceCallback and remove the CallbackType template.
template <template <typename> class CallbackType,
typename TaskReturnType,
typename ReplyArgType,
typename = EnableIfIsBaseCallback<CallbackType>>
bool PostTaskAndReplyWithResult(TaskRunner* task_runner,
const Location& from_here,
CallbackType<TaskReturnType()> task,
CallbackType<void(ReplyArgType)> reply) {
// std::unique_ptr used to avoid the need of a default constructor.
auto* result = new std::unique_ptr<TaskReturnType>();
return task_runner->PostTaskAndReply(
BindOnce(&internal::ReturnAsParamAdapter<TaskReturnType>, std::move(task),
BindOnce(&internal::ReplyAdapter<TaskReturnType, ReplyArgType>,
std::move(reply), Owned(result)));
} // namespace base