zircon/experimental/syscalls/fifo.test.fidl

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// !!! THIS FILE IS NOT YET USED !!!
// See //zircon/system/public/zircon/syscalls.banjo.
// !!! THIS FILE IS NOT YET USED !!!

library zz;

[Transport="Syscall"]
protocol Fifo {
    /// Create a fifo.
    [Out1="handle<fifo>:acquire",
     Out2="handle<fifo>:acquire"]
    Create(usize elem_count, usize elem_size, uint32 options) ->
        (status status, handle<fifo> out0, handle<fifo> out1);

    // TODO(scottmg): Size of |data| is tricky here! In particular it's a
    // elem_size * count large as if it were data<T> where sizeof(T) == elem_size.
    /// Read data from a fifo.
    [In0="handle<fifo>:rights=READ",
     In2="mutable<vector<byte>>",
     Out1="optional<usize>"]
    Read(handle<fifo> handle, usize elem_size, vector<byte> data) ->
        (status status, usize actual_count);

    // TODO(scottmg): Same as above for size of |data|.
    /// Write data to a fifo.
    [In0="handle<fifo>:rights=WRITE",
     Out1="optional<usize>"]
    Write(handle<fifo> handle, usize elem_size, vector<byte> data) ->
        (status status, usize actual_count);
};