blob: 46b0376b587341c8f5da81fb423a28c2a29aaa17 [file] [log] [blame]
use {AsyncRead, AsyncWrite};
use futures::{Async, Poll};
use std::{fmt, io};
/// A simple wrapper type which allows types that only implement
/// `std::io::Read` or `std::io::Write` to be used in contexts which expect
/// an `AsyncRead` or `AsyncWrite`.
/// If these types issue an error with the kind `io::ErrorKind::WouldBlock`,
/// it is expected that they will notify the current task on readiness.
/// Synchronous `std` types should not issue errors of this kind and
/// are safe to use in this context. However, using these types with
/// `AllowStdIo` will cause the event loop to block, so they should be used
/// with care.
#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
pub struct AllowStdIo<T>(T);
impl<T> AllowStdIo<T> {
/// Creates a new `AllowStdIo` from an existing IO object.
pub fn new(io: T) -> Self {
/// Returns a reference to the contained IO object.
pub fn get_ref(&self) -> &T {
/// Returns a mutable reference to the contained IO object.
pub fn get_mut(&mut self) -> &mut T {
&mut self.0
/// Consumes self and returns the contained IO object.
pub fn into_inner(self) -> T {
impl<T> io::Write for AllowStdIo<T> where T: io::Write {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
fn flush(&mut self) -> io::Result<()> {
fn write_all(&mut self, buf: &[u8]) -> io::Result<()> {
fn write_fmt(&mut self, fmt: fmt::Arguments) -> io::Result<()> {
impl<T> AsyncWrite for AllowStdIo<T> where T: io::Write {
fn shutdown(&mut self) -> Poll<(), io::Error> {
impl<T> io::Read for AllowStdIo<T> where T: io::Read {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
// TODO: implement the `initializer` fn when it stabilizes.
// See rust-lang/rust #42788
fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
fn read_to_string(&mut self, buf: &mut String) -> io::Result<usize> {
fn read_exact(&mut self, buf: &mut [u8]) -> io::Result<()> {
impl<T> AsyncRead for AllowStdIo<T> where T: io::Read {
// TODO: override prepare_uninitialized_buffer once `Read::initializer` is stable.
// See rust-lang/rust #42788