You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

105 lines
3.0 KiB

/*
* Copyright 2019 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include "common/bind.h"
#include "common/callback.h"
namespace bluetooth {
namespace common {
class IPostableContext {
public:
virtual ~IPostableContext(){};
virtual void Post(OnceClosure closure) = 0;
};
template <typename R, typename... Args>
class ContextualOnceCallback;
// A callback bound to an execution context that can be invoked only once.
template <typename R, typename... Args>
class ContextualOnceCallback<R(Args...)> {
public:
ContextualOnceCallback(common::OnceCallback<R(Args...)>&& callback, IPostableContext* context)
: callback_(std::move(callback)), context_(context) {}
constexpr ContextualOnceCallback() = default;
DISALLOW_COPY_AND_ASSIGN(ContextualOnceCallback);
ContextualOnceCallback(ContextualOnceCallback&&) noexcept = default;
ContextualOnceCallback& operator=(ContextualOnceCallback&&) noexcept = default;
void Invoke(Args... args) {
context_->Post(common::BindOnce(std::move(callback_), std::forward<Args>(args)...));
}
void InvokeIfNotEmpty(Args... args) {
if (context_ != nullptr) {
context_->Post(common::BindOnce(std::move(callback_), std::forward<Args>(args)...));
}
}
bool IsEmpty() {
return context_ == nullptr;
}
private:
common::OnceCallback<R(Args...)> callback_;
IPostableContext* context_;
};
template <typename R, typename... Args>
class ContextualCallback;
// A callback bound to an execution context that can be invoked multiple times.
template <typename R, typename... Args>
class ContextualCallback<R(Args...)> {
public:
ContextualCallback(common::Callback<R(Args...)>&& callback, IPostableContext* context)
: callback_(std::move(callback)), context_(context) {}
constexpr ContextualCallback() = default;
ContextualCallback(const ContextualCallback&) = default;
ContextualCallback& operator=(const ContextualCallback&) = default;
ContextualCallback(ContextualCallback&&) noexcept = default;
ContextualCallback& operator=(ContextualCallback&&) noexcept = default;
void Invoke(Args... args) {
context_->Post(common::BindOnce(callback_, std::forward<Args>(args)...));
}
void InvokeIfNotEmpty(Args... args) {
if (context_ != nullptr) {
context_->Post(common::BindOnce(callback_, std::forward<Args>(args)...));
}
}
bool IsEmpty() {
return context_ == nullptr;
}
private:
common::Callback<R(Args...)> callback_;
IPostableContext* context_;
};
} // namespace common
} // namespace bluetooth