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use crate::future::poll_fn;
use crate::io::{AsyncRead, AsyncWrite, PollEvented};
use crate::net::unix::split::{split, ReadHalf, WriteHalf};
use crate::net::unix::ucred::{self, UCred};
use std::convert::TryFrom;
use std::fmt;
use std::io::{self, Read, Write};
use std::mem::MaybeUninit;
use std::net::Shutdown;
use std::os::unix::io::{AsRawFd, RawFd};
use std::os::unix::net::{self, SocketAddr};
use std::path::Path;
use std::pin::Pin;
use std::task::{Context, Poll};
cfg_uds! {
/// A structure representing a connected Unix socket.
///
/// This socket can be connected directly with `UnixStream::connect` or accepted
/// from a listener with `UnixListener::incoming`. Additionally, a pair of
/// anonymous Unix sockets can be created with `UnixStream::pair`.
pub struct UnixStream {
io: PollEvented<mio_uds::UnixStream>,
}
}
impl UnixStream {
/// Connects to the socket named by `path`.
///
/// This function will create a new Unix socket and connect to the path
/// specified, associating the returned stream with the default event loop's
/// handle.
pub async fn connect<P>(path: P) -> io::Result<UnixStream>
where
P: AsRef<Path>,
{
let stream = mio_uds::UnixStream::connect(path)?;
let stream = UnixStream::new(stream)?;
poll_fn(|cx| stream.io.poll_write_ready(cx)).await?;
Ok(stream)
}
/// Consumes a `UnixStream` in the standard library and returns a
/// nonblocking `UnixStream` from this crate.
///
/// The returned stream will be associated with the given event loop
/// specified by `handle` and is ready to perform I/O.
///
/// # Panics
///
/// This function panics if thread-local runtime is not set.
///
/// The runtime is usually set implicitly when this function is called
/// from a future driven by a tokio runtime, otherwise runtime can be set
/// explicitly with [`Handle::enter`](crate::runtime::Handle::enter) function.
pub fn from_std(stream: net::UnixStream) -> io::Result<UnixStream> {
let stream = mio_uds::UnixStream::from_stream(stream)?;
let io = PollEvented::new(stream)?;
Ok(UnixStream { io })
}
/// Creates an unnamed pair of connected sockets.
///
/// This function will create a pair of interconnected Unix sockets for
/// communicating back and forth between one another. Each socket will
/// be associated with the default event loop's handle.
pub fn pair() -> io::Result<(UnixStream, UnixStream)> {
let (a, b) = mio_uds::UnixStream::pair()?;
let a = UnixStream::new(a)?;
let b = UnixStream::new(b)?;
Ok((a, b))
}
pub(crate) fn new(stream: mio_uds::UnixStream) -> io::Result<UnixStream> {
let io = PollEvented::new(stream)?;
Ok(UnixStream { io })
}
/// Returns the socket address of the local half of this connection.
pub fn local_addr(&self) -> io::Result<SocketAddr> {
self.io.get_ref().local_addr()
}
/// Returns the socket address of the remote half of this connection.
pub fn peer_addr(&self) -> io::Result<SocketAddr> {
self.io.get_ref().peer_addr()
}
/// Returns effective credentials of the process which called `connect` or `pair`.
pub fn peer_cred(&self) -> io::Result<UCred> {
ucred::get_peer_cred(self)
}
/// Returns the value of the `SO_ERROR` option.
pub fn take_error(&self) -> io::Result<Option<io::Error>> {
self.io.get_ref().take_error()
}
/// Shuts down the read, write, or both halves of this connection.
///
/// This function will cause all pending and future I/O calls on the
/// specified portions to immediately return with an appropriate value
/// (see the documentation of `Shutdown`).
pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
self.io.get_ref().shutdown(how)
}
/// Split a `UnixStream` into a read half and a write half, which can be used
/// to read and write the stream concurrently.
pub fn split(&mut self) -> (ReadHalf<'_>, WriteHalf<'_>) {
split(self)
}
}
impl TryFrom<UnixStream> for mio_uds::UnixStream {
type Error = io::Error;
/// Consumes value, returning the mio I/O object.
///
/// See [`PollEvented::into_inner`] for more details about
/// resource deregistration that happens during the call.
///
/// [`PollEvented::into_inner`]: crate::io::PollEvented::into_inner
fn try_from(value: UnixStream) -> Result<Self, Self::Error> {
value.io.into_inner()
}
}
impl TryFrom<net::UnixStream> for UnixStream {
type Error = io::Error;
/// Consumes stream, returning the tokio I/O object.
///
/// This is equivalent to
/// [`UnixStream::from_std(stream)`](UnixStream::from_std).
fn try_from(stream: net::UnixStream) -> io::Result<Self> {
Self::from_std(stream)
}
}
impl AsyncRead for UnixStream {
unsafe fn prepare_uninitialized_buffer(&self, _: &mut [MaybeUninit<u8>]) -> bool {
false
}
fn poll_read(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &mut [u8],
) -> Poll<io::Result<usize>> {
self.poll_read_priv(cx, buf)
}
}
impl AsyncWrite for UnixStream {
fn poll_write(
self: Pin<&mut Self>,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
self.poll_write_priv(cx, buf)
}
fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
Poll::Ready(Ok(()))
}
fn poll_shutdown(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
self.shutdown(std::net::Shutdown::Write)?;
Poll::Ready(Ok(()))
}
}
impl UnixStream {
// == Poll IO functions that takes `&self` ==
//
// They are not public because (taken from the doc of `PollEvented`):
//
// While `PollEvented` is `Sync` (if the underlying I/O type is `Sync`), the
// caller must ensure that there are at most two tasks that use a
// `PollEvented` instance concurrently. One for reading and one for writing.
// While violating this requirement is "safe" from a Rust memory model point
// of view, it will result in unexpected behavior in the form of lost
// notifications and tasks hanging.
pub(crate) fn poll_read_priv(
&self,
cx: &mut Context<'_>,
buf: &mut [u8],
) -> Poll<io::Result<usize>> {
ready!(self.io.poll_read_ready(cx, mio::Ready::readable()))?;
match self.io.get_ref().read(buf) {
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
self.io.clear_read_ready(cx, mio::Ready::readable())?;
Poll::Pending
}
x => Poll::Ready(x),
}
}
pub(crate) fn poll_write_priv(
&self,
cx: &mut Context<'_>,
buf: &[u8],
) -> Poll<io::Result<usize>> {
ready!(self.io.poll_write_ready(cx))?;
match self.io.get_ref().write(buf) {
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
self.io.clear_write_ready(cx)?;
Poll::Pending
}
x => Poll::Ready(x),
}
}
}
impl fmt::Debug for UnixStream {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
self.io.get_ref().fmt(f)
}
}
impl AsRawFd for UnixStream {
fn as_raw_fd(&self) -> RawFd {
self.io.get_ref().as_raw_fd()
}
}