82 lines
2.3 KiB
C++
82 lines
2.3 KiB
C++
/*
|
|
* Copyright 2020-2022 CM4all GmbH
|
|
* All rights reserved.
|
|
*
|
|
* author: Max Kellermann <mk@cm4all.com>
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
*
|
|
* - Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
*
|
|
* - Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the
|
|
* distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
|
|
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
|
|
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
|
|
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
|
|
* OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "io/FileDescriptor.hxx"
|
|
|
|
#include <liburing.h>
|
|
|
|
namespace Uring {
|
|
|
|
/**
|
|
* Low-level C++ wrapper for a `struct io_uring`. It provides simple
|
|
* wrappers to liburing functions and throws std::system_error on
|
|
* errors.
|
|
*/
|
|
class Ring {
|
|
struct io_uring ring;
|
|
|
|
public:
|
|
Ring(unsigned entries, unsigned flags);
|
|
|
|
~Ring() noexcept {
|
|
io_uring_queue_exit(&ring);
|
|
}
|
|
|
|
Ring(const Ring &) = delete;
|
|
Ring &operator=(const Ring &) = delete;
|
|
|
|
FileDescriptor GetFileDescriptor() const noexcept {
|
|
return FileDescriptor(ring.ring_fd);
|
|
}
|
|
|
|
struct io_uring_sqe *GetSubmitEntry() noexcept {
|
|
return io_uring_get_sqe(&ring);
|
|
}
|
|
|
|
void Submit();
|
|
|
|
struct io_uring_cqe *WaitCompletion();
|
|
|
|
/**
|
|
* @return a completion queue entry or nullptr on EAGAIN
|
|
*/
|
|
struct io_uring_cqe *PeekCompletion();
|
|
|
|
void SeenCompletion(struct io_uring_cqe &cqe) noexcept {
|
|
io_uring_cqe_seen(&ring, &cqe);
|
|
}
|
|
};
|
|
|
|
} // namespace Uring
|