platform_system_core/init/interprocess_fifo.h
Bart Van Assche 1693f420d4 init: Introduce class InterprocessFifo
Prepare for introducing a second interprocess communication channel by
introducing the class InterprocessFifo. Stop using std::unique_ptr<> for
holding the pipe file descriptors. Handle EOF consistently.

Bug: 213617178
Change-Id: Ic0cf18d3d8ea61b8ee17e64de8a9df2736e26728
Signed-off-by: Bart Van Assche <bvanassche@google.com>
2022-10-25 06:56:50 -07:00

52 lines
1.6 KiB
C++

/*
* Copyright (C) 2022 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 <array>
#include <android-base/result.h>
namespace android {
namespace init {
// A FIFO for inter-process communication that uses a Unix pipe internally.
class InterprocessFifo {
public:
template <typename T>
using Result = ::android::base::Result<T>;
InterprocessFifo() noexcept;
InterprocessFifo(const InterprocessFifo& orig) noexcept = delete;
InterprocessFifo(InterprocessFifo&& orig) noexcept;
InterprocessFifo& operator=(const InterprocessFifo& orig) noexcept = delete;
InterprocessFifo& operator=(InterprocessFifo&& orig) noexcept = delete;
~InterprocessFifo() noexcept;
void CloseReadFd() noexcept;
void CloseWriteFd() noexcept;
void Close() noexcept;
Result<void> Initialize() noexcept;
Result<void> Write(uint8_t byte) noexcept;
Result<uint8_t> Read() noexcept;
private:
static void CloseFd(int& fd) noexcept;
std::array<int, 2> fds_;
};
} // namespace init
} // namespace android