//===----------------------------------------------------------------------===//
//
// This source file is part of the SwiftNIO open source project
//
// Copyright (c) 2017-2018 Apple Inc. and the SwiftNIO project authors
// Licensed under Apache License v2.0
//
// See LICENSE.txt for license information
// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
//
// SPDX-License-Identifier: Apache-2.0
//
//===----------------------------------------------------------------------===//

public protocol FileDescriptor {

    /// Will be called with the file descriptor if still open, if not it will
    /// throw an `IOError`.
    ///
    /// The ownership of the file descriptor must not escape the `body` as it's completely managed by the
    /// implementation of the `FileDescriptor` protocol.
    ///
    /// - parameters:
    ///     - body: The closure to execute if the `FileDescriptor` is still open.
    /// - throws: If either the `FileDescriptor` was closed before or the closure throws by itself.
    func withUnsafeFileDescriptor<T>(_ body: (CInt) throws -> T) throws -> T

    /// `true` if this `FileDescriptor` is open (which means it was not closed yet).
    var isOpen: Bool { get }

    /// Close this `FileDescriptor`.
    func close() throws
}