Merging upstream version 1.72.1+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 2332 insertions, 109 deletions

diff --git a/vendor/tokio/src/net/unix/datagram/socket.rs b/vendor/tokio/src/net/unix/datagram/socket.rs
index 2d2177803..c97d101aa 100644
--- a/vendor/tokio/src/net/unix/datagram/socket.rs
+++ b/vendor/tokio/src/net/unix/datagram/socket.rs
@@ -1,10 +1,11 @@
 use crate::io::{Interest, PollEvented, ReadBuf, Ready};
 use crate::net::unix::SocketAddr;
 
-use std::convert::TryFrom;
 use std::fmt;
 use std::io;
 use std::net::Shutdown;
+#[cfg(not(tokio_no_as_fd))]
+use std::os::unix::io::{AsFd, BorrowedFd};
 use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
 use std::os::unix::net;
 use std::path::Path;
@@ -90,13 +91,14 @@ cfg_net_unix! {
     /// # Ok(())
     /// # }
     /// ```
+    #[cfg_attr(docsrs, doc(alias = "uds"))]
     pub struct UnixDatagram {
         io: PollEvented<mio::net::UnixDatagram>,
     }
 }
 
 impl UnixDatagram {
-    /// Wait for any of the requested ready states.
+    /// Waits for any of the requested ready states.
     ///
     /// This function is usually paired with `try_recv()` or `try_send()`. It
     /// can be used to concurrently recv / send to the same socket on a single
@@ -104,7 +106,9 @@ impl UnixDatagram {
     ///
     /// The function may complete without the socket being ready. This is a
     /// false-positive and attempting an operation will return with
-    /// `io::ErrorKind::WouldBlock`.
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
     ///
     /// # Cancel safety
     ///
@@ -169,7 +173,7 @@ impl UnixDatagram {
         Ok(event.ready)
     }
 
-    /// Wait for the socket to become writable.
+    /// Waits for the socket to become writable.
     ///
     /// This function is equivalent to `ready(Interest::WRITABLE)` and is
     /// usually paired with `try_send()` or `try_send_to()`.
@@ -226,7 +230,40 @@ impl UnixDatagram {
         Ok(())
     }
 
-    /// Wait for the socket to become readable.
+    /// Polls for write/send readiness.
+    ///
+    /// If the socket is not currently ready for sending, this method will
+    /// store a clone of the `Waker` from the provided `Context`. When the socket
+    /// becomes ready for sending, `Waker::wake` will be called on the
+    /// waker.
+    ///
+    /// Note that on multiple calls to `poll_send_ready` or `poll_send`, only
+    /// the `Waker` from the `Context` passed to the most recent call is
+    /// scheduled to receive a wakeup. (However, `poll_recv_ready` retains a
+    /// second, independent waker.)
+    ///
+    /// This function is intended for cases where creating and pinning a future
+    /// via [`writable`] is not feasible. Where possible, using [`writable`] is
+    /// preferred, as this supports polling from multiple tasks at once.
+    ///
+    /// # Return value
+    ///
+    /// The function returns:
+    ///
+    /// * `Poll::Pending` if the socket is not ready for writing.
+    /// * `Poll::Ready(Ok(()))` if the socket is ready for writing.
+    /// * `Poll::Ready(Err(e))` if an error is encountered.
+    ///
+    /// # Errors
+    ///
+    /// This function may encounter any standard I/O error except `WouldBlock`.
+    ///
+    /// [`writable`]: method@Self::writable
+    pub fn poll_send_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.io.registration().poll_write_ready(cx).map_ok(|_| ())
+    }
+
+    /// Waits for the socket to become readable.
     ///
     /// This function is equivalent to `ready(Interest::READABLE)` and is usually
     /// paired with `try_recv()`.
@@ -289,6 +326,39 @@ impl UnixDatagram {
         Ok(())
     }
 
+    /// Polls for read/receive readiness.
+    ///
+    /// If the socket is not currently ready for receiving, this method will
+    /// store a clone of the `Waker` from the provided `Context`. When the
+    /// socket becomes ready for reading, `Waker::wake` will be called on the
+    /// waker.
+    ///
+    /// Note that on multiple calls to `poll_recv_ready`, `poll_recv` or
+    /// `poll_peek`, only the `Waker` from the `Context` passed to the most
+    /// recent call is scheduled to receive a wakeup. (However,
+    /// `poll_send_ready` retains a second, independent waker.)
+    ///
+    /// This function is intended for cases where creating and pinning a future
+    /// via [`readable`] is not feasible. Where possible, using [`readable`] is
+    /// preferred, as this supports polling from multiple tasks at once.
+    ///
+    /// # Return value
+    ///
+    /// The function returns:
+    ///
+    /// * `Poll::Pending` if the socket is not ready for reading.
+    /// * `Poll::Ready(Ok(()))` if the socket is ready for reading.
+    /// * `Poll::Ready(Err(e))` if an error is encountered.
+    ///
+    /// # Errors
+    ///
+    /// This function may encounter any standard I/O error except `WouldBlock`.
+    ///
+    /// [`readable`]: method@Self::readable
+    pub fn poll_recv_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.io.registration().poll_read_ready(cx).map_ok(|_| ())
+    }
+
     /// Creates a new `UnixDatagram` bound to the specified path.
     ///
     /// # Examples
@@ -358,13 +428,21 @@ impl UnixDatagram {
     /// Creates new `UnixDatagram` from a `std::os::unix::net::UnixDatagram`.
     ///
     /// This function is intended to be used to wrap a UnixDatagram from the
-    /// standard library in the Tokio equivalent. The conversion assumes
-    /// nothing about the underlying datagram; it is left up to the user to set
-    /// it in non-blocking mode.
+    /// standard library in the Tokio equivalent.
+    ///
+    /// # Notes
+    ///
+    /// The caller is responsible for ensuring that the socker is in
+    /// non-blocking mode. Otherwise all I/O operations on the socket
+    /// will block the thread, which will cause unexpected behavior.
+    /// Non-blocking mode can be set using [`set_nonblocking`].
+    ///
+    /// [`set_nonblocking`]: std::os::unix::net::UnixDatagram::set_nonblocking
     ///
     /// # Panics
     ///
-    /// This function panics if thread-local runtime is not set.
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
     ///
     /// The runtime is usually set implicitly when this function is called
     /// from a future driven by a Tokio runtime, otherwise runtime can be set
@@ -391,30 +469,29 @@ impl UnixDatagram {
     /// # Ok(())
     /// # }
     /// ```
+    #[track_caller]
     pub fn from_std(datagram: net::UnixDatagram) -> io::Result<UnixDatagram> {
         let socket = mio::net::UnixDatagram::from_std(datagram);
         let io = PollEvented::new(socket)?;
         Ok(UnixDatagram { io })
     }
 
-    /// Turn a [`tokio::net::UnixDatagram`] into a [`std::os::unix::net::UnixDatagram`].
+    /// Turns a [`tokio::net::UnixDatagram`] into a [`std::os::unix::net::UnixDatagram`].
     ///
     /// The returned [`std::os::unix::net::UnixDatagram`] will have nonblocking
-    /// mode set as `true`.  Use [`set_nonblocking`] to change the blocking mode
+    /// mode set as `true`. Use [`set_nonblocking`] to change the blocking mode
     /// if needed.
     ///
     /// # Examples
     ///
     /// ```rust,no_run
-    /// use std::error::Error;
-    ///
-    /// #[tokio::main]
-    /// async fn main() -> Result<(), Box<dyn Error>> {
-    ///     let tokio_socket = tokio::net::UnixDatagram::bind("127.0.0.1:0")?;
-    ///     let std_socket = tokio_socket.into_std()?;
-    ///     std_socket.set_nonblocking(false)?;
-    ///     Ok(())
-    /// }
+    /// # use std::error::Error;
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let tokio_socket = tokio::net::UnixDatagram::bind("/path/to/the/socket")?;
+    /// let std_socket = tokio_socket.into_std()?;
+    /// std_socket.set_nonblocking(false)?;
+    /// # Ok(())
+    /// # }
     /// ```
     ///
     /// [`tokio::net::UnixDatagram`]: UnixDatagram
@@ -548,7 +625,7 @@ impl UnixDatagram {
             .await
     }
 
-    /// Try to send a datagram to the peer without waiting.
+    /// Tries to send a datagram to the peer without waiting.
     ///
     /// # Examples
     ///
@@ -592,7 +669,7 @@ impl UnixDatagram {
             .try_io(Interest::WRITABLE, || self.io.send(buf))
     }
 
-    /// Try to send a datagram to the peer without waiting.
+    /// Tries to send a datagram to the peer without waiting.
     ///
     /// # Examples
     ///
@@ -678,7 +755,7 @@ impl UnixDatagram {
             .await
     }
 
-    /// Try to receive a datagram from the peer without waiting.
+    /// Tries to receive a datagram from the peer without waiting.
     ///
     /// # Examples
     ///
@@ -729,7 +806,9 @@ impl UnixDatagram {
     }
 
     cfg_io_util! {
-        /// Try to receive data from the socket without waiting.
+        /// Tries to receive data from the socket without waiting.
+        ///
+        /// This method can be used even if `buf` is uninitialized.
         ///
         /// # Examples
         ///
@@ -778,7 +857,7 @@ impl UnixDatagram {
 
                 // Safety: We trust `UnixDatagram::recv_from` to have filled up `n` bytes in the
                 // buffer.
-                let (n, addr) = (&*self.io).recv_from(dst)?;
+                let (n, addr) = (*self.io).recv_from(dst)?;
 
                 unsafe {
                     buf.advance_mut(n);
@@ -790,9 +869,64 @@ impl UnixDatagram {
             Ok((n, SocketAddr(addr)))
         }
 
-        /// Try to read data from the stream into the provided buffer, advancing the
+        /// Receives from the socket, advances the
+        /// buffer's internal cursor and returns how many bytes were read and the origin.
+        ///
+        /// This method can be used even if `buf` is uninitialized.
+        ///
+        /// # Examples
+        /// ```
+        /// # use std::error::Error;
+        /// # #[tokio::main]
+        /// # async fn main() -> Result<(), Box<dyn Error>> {
+        /// use tokio::net::UnixDatagram;
+        /// use tempfile::tempdir;
+        ///
+        /// // We use a temporary directory so that the socket
+        /// // files left by the bound sockets will get cleaned up.
+        /// let tmp = tempdir()?;
+        ///
+        /// // Bind each socket to a filesystem path
+        /// let tx_path = tmp.path().join("tx");
+        /// let tx = UnixDatagram::bind(&tx_path)?;
+        /// let rx_path = tmp.path().join("rx");
+        /// let rx = UnixDatagram::bind(&rx_path)?;
+        ///
+        /// let bytes = b"hello world";
+        /// tx.send_to(bytes, &rx_path).await?;
+        ///
+        /// let mut buf = Vec::with_capacity(24);
+        /// let (size, addr) = rx.recv_buf_from(&mut buf).await?;
+        ///
+        /// let dgram = &buf[..size];
+        /// assert_eq!(dgram, bytes);
+        /// assert_eq!(addr.as_pathname().unwrap(), &tx_path);
+        ///
+        /// # Ok(())
+        /// # }
+        /// ```
+        pub async fn recv_buf_from<B: BufMut>(&self, buf: &mut B) -> io::Result<(usize, SocketAddr)> {
+            self.io.registration().async_io(Interest::READABLE, || {
+                let dst = buf.chunk_mut();
+                let dst =
+                    unsafe { &mut *(dst as *mut _ as *mut [std::mem::MaybeUninit<u8>] as *mut [u8]) };
+
+                // Safety: We trust `UnixDatagram::recv_from` to have filled up `n` bytes in the
+                // buffer.
+                let (n, addr) = (*self.io).recv_from(dst)?;
+
+                unsafe {
+                    buf.advance_mut(n);
+                }
+                Ok((n,SocketAddr(addr)))
+            }).await
+        }
+
+        /// Tries to read data from the stream into the provided buffer, advancing the
         /// buffer's internal cursor, returning how many bytes were read.
         ///
+        /// This method can be used even if `buf` is uninitialized.
+        ///
         /// # Examples
         ///
         /// ```no_run
@@ -841,7 +975,7 @@ impl UnixDatagram {
 
                 // Safety: We trust `UnixDatagram::recv` to have filled up `n` bytes in the
                 // buffer.
-                let n = (&*self.io).recv(dst)?;
+                let n = (*self.io).recv(dst)?;
 
                 unsafe {
                     buf.advance_mut(n);
@@ -850,6 +984,52 @@ impl UnixDatagram {
                 Ok(n)
             })
         }
+
+        /// Receives data from the socket from the address to which it is connected,
+        /// advancing the buffer's internal cursor, returning how many bytes were read.
+        ///
+        /// This method can be used even if `buf` is uninitialized.
+        ///
+        /// # Examples
+        /// ```
+        /// # use std::error::Error;
+        /// # #[tokio::main]
+        /// # async fn main() -> Result<(), Box<dyn Error>> {
+        /// use tokio::net::UnixDatagram;
+        ///
+        /// // Create the pair of sockets
+        /// let (sock1, sock2) = UnixDatagram::pair()?;
+        ///
+        /// // Since the sockets are paired, the paired send/recv
+        /// // functions can be used
+        /// let bytes = b"hello world";
+        /// sock1.send(bytes).await?;
+        ///
+        /// let mut buff = Vec::with_capacity(24);
+        /// let size = sock2.recv_buf(&mut buff).await?;
+        ///
+        /// let dgram = &buff[..size];
+        /// assert_eq!(dgram, bytes);
+        ///
+        /// # Ok(())
+        /// # }
+        /// ```
+        pub async fn recv_buf<B: BufMut>(&self, buf: &mut B) -> io::Result<usize> {
+            self.io.registration().async_io(Interest::READABLE, || {
+                let dst = buf.chunk_mut();
+                let dst =
+                    unsafe { &mut *(dst as *mut _ as *mut [std::mem::MaybeUninit<u8>] as *mut [u8]) };
+
+                // Safety: We trust `UnixDatagram::recv_from` to have filled up `n` bytes in the
+                // buffer.
+                let n = (*self.io).recv(dst)?;
+
+                unsafe {
+                    buf.advance_mut(n);
+                }
+                Ok(n)
+            }).await
+        }
     }
 
     /// Sends data on the socket to the specified address.
@@ -1091,7 +1271,7 @@ impl UnixDatagram {
         Poll::Ready(Ok(()))
     }
 
-    /// Try to receive data from the socket without waiting.
+    /// Tries to receive data from the socket without waiting.
     ///
     /// # Examples
     ///
@@ -1143,6 +1323,84 @@ impl UnixDatagram {
         Ok((n, SocketAddr(addr)))
     }
 
+    /// Tries to read or write from the socket using a user-provided IO operation.
+    ///
+    /// If the socket is ready, the provided closure is called. The closure
+    /// should attempt to perform IO operation on the socket by manually
+    /// calling the appropriate syscall. If the operation fails because the
+    /// socket is not actually ready, then the closure should return a
+    /// `WouldBlock` error and the readiness flag is cleared. The return value
+    /// of the closure is then returned by `try_io`.
+    ///
+    /// If the socket is not ready, then the closure is not called
+    /// and a `WouldBlock` error is returned.
+    ///
+    /// The closure should only return a `WouldBlock` error if it has performed
+    /// an IO operation on the socket that failed due to the socket not being
+    /// ready. Returning a `WouldBlock` error in any other situation will
+    /// incorrectly clear the readiness flag, which can cause the socket to
+    /// behave incorrectly.
+    ///
+    /// The closure should not perform the IO operation using any of the methods
+    /// defined on the Tokio `UnixDatagram` type, as this will mess with the
+    /// readiness flag and can cause the socket to behave incorrectly.
+    ///
+    /// This method is not intended to be used with combined interests.
+    /// The closure should perform only one type of IO operation, so it should not
+    /// require more than one ready state. This method may panic or sleep forever
+    /// if it is called with a combined interest.
+    ///
+    /// Usually, [`readable()`], [`writable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`readable()`]: UnixDatagram::readable()
+    /// [`writable()`]: UnixDatagram::writable()
+    /// [`ready()`]: UnixDatagram::ready()
+    pub fn try_io<R>(
+        &self,
+        interest: Interest,
+        f: impl FnOnce() -> io::Result<R>,
+    ) -> io::Result<R> {
+        self.io
+            .registration()
+            .try_io(interest, || self.io.try_io(f))
+    }
+
+    /// Reads or writes from the socket using a user-provided IO operation.
+    ///
+    /// The readiness of the socket is awaited and when the socket is ready,
+    /// the provided closure is called. The closure should attempt to perform
+    /// IO operation on the socket by manually calling the appropriate syscall.
+    /// If the operation fails because the socket is not actually ready,
+    /// then the closure should return a `WouldBlock` error. In such case the
+    /// readiness flag is cleared and the socket readiness is awaited again.
+    /// This loop is repeated until the closure returns an `Ok` or an error
+    /// other than `WouldBlock`.
+    ///
+    /// The closure should only return a `WouldBlock` error if it has performed
+    /// an IO operation on the socket that failed due to the socket not being
+    /// ready. Returning a `WouldBlock` error in any other situation will
+    /// incorrectly clear the readiness flag, which can cause the socket to
+    /// behave incorrectly.
+    ///
+    /// The closure should not perform the IO operation using any of the methods
+    /// defined on the Tokio `UnixDatagram` type, as this will mess with the
+    /// readiness flag and can cause the socket to behave incorrectly.
+    ///
+    /// This method is not intended to be used with combined interests.
+    /// The closure should perform only one type of IO operation, so it should not
+    /// require more than one ready state. This method may panic or sleep forever
+    /// if it is called with a combined interest.
+    pub async fn async_io<R>(
+        &self,
+        interest: Interest,
+        mut f: impl FnMut() -> io::Result<R>,
+    ) -> io::Result<R> {
+        self.io
+            .registration()
+            .async_io(interest, || self.io.try_io(&mut f))
+            .await
+    }
+
     /// Returns the local address that this socket is bound to.
     ///
     /// # Examples
@@ -1319,3 +1577,10 @@ impl AsRawFd for UnixDatagram {
         self.io.as_raw_fd()
     }
 }
+
+#[cfg(not(tokio_no_as_fd))]
+impl AsFd for UnixDatagram {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+    }
+}
diff --git a/vendor/tokio/src/net/unix/listener.rs b/vendor/tokio/src/net/unix/listener.rs
index efb9503d4..37a5a4ae4 100644
--- a/vendor/tokio/src/net/unix/listener.rs
+++ b/vendor/tokio/src/net/unix/listener.rs
@@ -1,9 +1,10 @@
 use crate::io::{Interest, PollEvented};
 use crate::net::unix::{SocketAddr, UnixStream};
 
-use std::convert::TryFrom;
 use std::fmt;
 use std::io;
+#[cfg(not(tokio_no_as_fd))]
+use std::os::unix::io::{AsFd, BorrowedFd};
 use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
 use std::os::unix::net;
 use std::path::Path;
@@ -44,6 +45,7 @@ cfg_net_unix! {
     ///     }
     /// }
     /// ```
+    #[cfg_attr(docsrs, doc(alias = "uds"))]
     pub struct UnixListener {
         io: PollEvented<mio::net::UnixListener>,
     }
@@ -54,11 +56,13 @@ impl UnixListener {
     ///
     /// # Panics
     ///
-    /// This function panics if thread-local runtime is not set.
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
     ///
     /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    #[track_caller]
     pub fn bind<P>(path: P) -> io::Result<UnixListener>
     where
         P: AsRef<Path>,
@@ -71,40 +75,62 @@ impl UnixListener {
     /// Creates new `UnixListener` from a `std::os::unix::net::UnixListener `.
     ///
     /// This function is intended to be used to wrap a UnixListener from the
-    /// standard library in the Tokio equivalent. The conversion assumes
-    /// nothing about the underlying listener; it is left up to the user to set
-    /// it in non-blocking mode.
+    /// standard library in the Tokio equivalent.
+    ///
+    /// # Notes
+    ///
+    /// The caller is responsible for ensuring that the listener is in
+    /// non-blocking mode. Otherwise all I/O operations on the listener
+    /// will block the thread, which will cause unexpected behavior.
+    /// Non-blocking mode can be set using [`set_nonblocking`].
+    ///
+    /// [`set_nonblocking`]: std::os::unix::net::UnixListener::set_nonblocking
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::UnixListener;
+    /// use std::os::unix::net::UnixListener as StdUnixListener;
+    /// # use std::error::Error;
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let std_listener = StdUnixListener::bind("/path/to/the/socket")?;
+    /// std_listener.set_nonblocking(true)?;
+    /// let listener = UnixListener::from_std(std_listener)?;
+    /// # Ok(())
+    /// # }
+    /// ```
     ///
     /// # Panics
     ///
-    /// This function panics if thread-local runtime is not set.
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
     ///
     /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    #[track_caller]
     pub fn from_std(listener: net::UnixListener) -> io::Result<UnixListener> {
         let listener = mio::net::UnixListener::from_std(listener);
         let io = PollEvented::new(listener)?;
         Ok(UnixListener { io })
     }
 
-    /// Turn a [`tokio::net::UnixListener`] into a [`std::os::unix::net::UnixListener`].
+    /// Turns a [`tokio::net::UnixListener`] into a [`std::os::unix::net::UnixListener`].
     ///
     /// The returned [`std::os::unix::net::UnixListener`] will have nonblocking mode
-    /// set as `true`.  Use [`set_nonblocking`] to change the blocking mode if needed.
+    /// set as `true`. Use [`set_nonblocking`] to change the blocking mode if needed.
     ///
     /// # Examples
     ///
     /// ```rust,no_run
-    /// use std::error::Error;
-    ///
-    /// #[tokio::main]
-    /// async fn main() -> Result<(), Box<dyn Error>> {
-    ///     let tokio_listener = tokio::net::UnixListener::bind("127.0.0.1:0")?;
-    ///     let std_listener = tokio_listener.into_std()?;
-    ///     std_listener.set_nonblocking(false)?;
-    ///     Ok(())
-    /// }
+    /// # use std::error::Error;
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let tokio_listener = tokio::net::UnixListener::bind("/path/to/the/socket")?;
+    /// let std_listener = tokio_listener.into_std()?;
+    /// std_listener.set_nonblocking(false)?;
+    /// # Ok(())
+    /// # }
     /// ```
     ///
     /// [`tokio::net::UnixListener`]: UnixListener
@@ -184,3 +210,10 @@ impl AsRawFd for UnixListener {
         self.io.as_raw_fd()
     }
 }
+
+#[cfg(not(tokio_no_as_fd))]
+impl AsFd for UnixListener {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+    }
+}
diff --git a/vendor/tokio/src/net/unix/mod.rs b/vendor/tokio/src/net/unix/mod.rs
index c3046f17e..a49b70af3 100644
--- a/vendor/tokio/src/net/unix/mod.rs
+++ b/vendor/tokio/src/net/unix/mod.rs
@@ -1,5 +1,4 @@
-//! Unix domain socket utility types
-
+//! Unix specific network types.
 // This module does not currently provide any public API, but it was
 // unintentionally defined as a public module. Hide it from the documentation
 // instead of changing it to a private module to avoid breakage.
@@ -22,3 +21,17 @@ pub(crate) use stream::UnixStream;
 
 mod ucred;
 pub use ucred::UCred;
+
+pub mod pipe;
+
+/// A type representing process and process group IDs.
+#[allow(non_camel_case_types)]
+pub type uid_t = u32;
+
+/// A type representing user ID.
+#[allow(non_camel_case_types)]
+pub type gid_t = u32;
+
+/// A type representing group ID.
+#[allow(non_camel_case_types)]
+pub type pid_t = i32;
diff --git a/vendor/tokio/src/net/unix/pipe.rs b/vendor/tokio/src/net/unix/pipe.rs
new file mode 100644
index 000000000..188ac68b1
--- /dev/null
+++ b/vendor/tokio/src/net/unix/pipe.rs
@@ -0,0 +1,1222 @@
+//! Unix pipe types.
+
+use crate::io::interest::Interest;
+use crate::io::{AsyncRead, AsyncWrite, PollEvented, ReadBuf, Ready};
+
+use mio::unix::pipe as mio_pipe;
+use std::fs::File;
+use std::io::{self, Read, Write};
+use std::os::unix::fs::{FileTypeExt, OpenOptionsExt};
+#[cfg(not(tokio_no_as_fd))]
+use std::os::unix::io::{AsFd, BorrowedFd};
+use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
+use std::path::Path;
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+cfg_io_util! {
+    use bytes::BufMut;
+}
+
+/// Options and flags which can be used to configure how a FIFO file is opened.
+///
+/// This builder allows configuring how to create a pipe end from a FIFO file.
+/// Generally speaking, when using `OpenOptions`, you'll first call [`new`],
+/// then chain calls to methods to set each option, then call either
+/// [`open_receiver`] or [`open_sender`], passing the path of the FIFO file you
+/// are trying to open. This will give you a [`io::Result`][result] with a pipe
+/// end inside that you can further operate on.
+///
+/// [`new`]: OpenOptions::new
+/// [`open_receiver`]: OpenOptions::open_receiver
+/// [`open_sender`]: OpenOptions::open_sender
+/// [result]: std::io::Result
+///
+/// # Examples
+///
+/// Opening a pair of pipe ends from a FIFO file:
+///
+/// ```no_run
+/// use tokio::net::unix::pipe;
+/// # use std::error::Error;
+///
+/// const FIFO_NAME: &str = "path/to/a/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn Error>> {
+/// let rx = pipe::OpenOptions::new().open_receiver(FIFO_NAME)?;
+/// let tx = pipe::OpenOptions::new().open_sender(FIFO_NAME)?;
+/// # Ok(())
+/// # }
+/// ```
+///
+/// Opening a [`Sender`] on Linux when you are sure the file is a FIFO:
+///
+/// ```ignore
+/// use tokio::net::unix::pipe;
+/// use nix::{unistd::mkfifo, sys::stat::Mode};
+/// # use std::error::Error;
+///
+/// // Our program has exclusive access to this path.
+/// const FIFO_NAME: &str = "path/to/a/new/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn Error>> {
+/// mkfifo(FIFO_NAME, Mode::S_IRWXU)?;
+/// let tx = pipe::OpenOptions::new()
+///     .read_write(true)
+///     .unchecked(true)
+///     .open_sender(FIFO_NAME)?;
+/// # Ok(())
+/// # }
+/// ```
+#[derive(Clone, Debug)]
+pub struct OpenOptions {
+    #[cfg(target_os = "linux")]
+    read_write: bool,
+    unchecked: bool,
+}
+
+impl OpenOptions {
+    /// Creates a blank new set of options ready for configuration.
+    ///
+    /// All options are initially set to `false`.
+    pub fn new() -> OpenOptions {
+        OpenOptions {
+            #[cfg(target_os = "linux")]
+            read_write: false,
+            unchecked: false,
+        }
+    }
+
+    /// Sets the option for read-write access.
+    ///
+    /// This option, when true, will indicate that a FIFO file will be opened
+    /// in read-write access mode. This operation is not defined by the POSIX
+    /// standard and is only guaranteed to work on Linux.
+    ///
+    /// # Examples
+    ///
+    /// Opening a [`Sender`] even if there are no open reading ends:
+    ///
+    /// ```ignore
+    /// use tokio::net::unix::pipe;
+    ///
+    /// let tx = pipe::OpenOptions::new()
+    ///     .read_write(true)
+    ///     .open_sender("path/to/a/fifo");
+    /// ```
+    ///
+    /// Opening a resilient [`Receiver`] i.e. a reading pipe end which will not
+    /// fail with [`UnexpectedEof`] during reading if all writing ends of the
+    /// pipe close the FIFO file.
+    ///
+    /// [`UnexpectedEof`]: std::io::ErrorKind::UnexpectedEof
+    ///
+    /// ```ignore
+    /// use tokio::net::unix::pipe;
+    ///
+    /// let tx = pipe::OpenOptions::new()
+    ///     .read_write(true)
+    ///     .open_receiver("path/to/a/fifo");
+    /// ```
+    #[cfg(target_os = "linux")]
+    #[cfg_attr(docsrs, doc(cfg(target_os = "linux")))]
+    pub fn read_write(&mut self, value: bool) -> &mut Self {
+        self.read_write = value;
+        self
+    }
+
+    /// Sets the option to skip the check for FIFO file type.
+    ///
+    /// By default, [`open_receiver`] and [`open_sender`] functions will check
+    /// if the opened file is a FIFO file. Set this option to `true` if you are
+    /// sure the file is a FIFO file.
+    ///
+    /// [`open_receiver`]: OpenOptions::open_receiver
+    /// [`open_sender`]: OpenOptions::open_sender
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use nix::{unistd::mkfifo, sys::stat::Mode};
+    /// # use std::error::Error;
+    ///
+    /// // Our program has exclusive access to this path.
+    /// const FIFO_NAME: &str = "path/to/a/new/fifo";
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// mkfifo(FIFO_NAME, Mode::S_IRWXU)?;
+    /// let rx = pipe::OpenOptions::new()
+    ///     .unchecked(true)
+    ///     .open_receiver(FIFO_NAME)?;
+    /// # Ok(())
+    /// # }
+    /// ```
+    pub fn unchecked(&mut self, value: bool) -> &mut Self {
+        self.unchecked = value;
+        self
+    }
+
+    /// Creates a [`Receiver`] from a FIFO file with the options specified by `self`.
+    ///
+    /// This function will open the FIFO file at the specified path, possibly
+    /// check if it is a pipe, and associate the pipe with the default event
+    /// loop for reading.
+    ///
+    /// # Errors
+    ///
+    /// If the file type check fails, this function will fail with `io::ErrorKind::InvalidInput`.
+    /// This function may also fail with other standard OS errors.
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn open_receiver<P: AsRef<Path>>(&self, path: P) -> io::Result<Receiver> {
+        let file = self.open(path.as_ref(), PipeEnd::Receiver)?;
+        Receiver::from_file_unchecked(file)
+    }
+
+    /// Creates a [`Sender`] from a FIFO file with the options specified by `self`.
+    ///
+    /// This function will open the FIFO file at the specified path, possibly
+    /// check if it is a pipe, and associate the pipe with the default event
+    /// loop for writing.
+    ///
+    /// # Errors
+    ///
+    /// If the file type check fails, this function will fail with `io::ErrorKind::InvalidInput`.
+    /// If the file is not opened in read-write access mode and the file is not
+    /// currently open for reading, this function will fail with `ENXIO`.
+    /// This function may also fail with other standard OS errors.
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn open_sender<P: AsRef<Path>>(&self, path: P) -> io::Result<Sender> {
+        let file = self.open(path.as_ref(), PipeEnd::Sender)?;
+        Sender::from_file_unchecked(file)
+    }
+
+    fn open(&self, path: &Path, pipe_end: PipeEnd) -> io::Result<File> {
+        let mut options = std::fs::OpenOptions::new();
+        options
+            .read(pipe_end == PipeEnd::Receiver)
+            .write(pipe_end == PipeEnd::Sender)
+            .custom_flags(libc::O_NONBLOCK);
+
+        #[cfg(target_os = "linux")]
+        if self.read_write {
+            options.read(true).write(true);
+        }
+
+        let file = options.open(path)?;
+
+        if !self.unchecked && !is_fifo(&file)? {
+            return Err(io::Error::new(io::ErrorKind::InvalidInput, "not a pipe"));
+        }
+
+        Ok(file)
+    }
+}
+
+impl Default for OpenOptions {
+    fn default() -> OpenOptions {
+        OpenOptions::new()
+    }
+}
+
+#[derive(Clone, Copy, PartialEq, Eq, Debug)]
+enum PipeEnd {
+    Sender,
+    Receiver,
+}
+
+/// Writing end of a Unix pipe.
+///
+/// It can be constructed from a FIFO file with [`OpenOptions::open_sender`].
+///
+/// Opening a named pipe for writing involves a few steps.
+/// Call to [`OpenOptions::open_sender`] might fail with an error indicating
+/// different things:
+///
+/// * [`io::ErrorKind::NotFound`] - There is no file at the specified path.
+/// * [`io::ErrorKind::InvalidInput`] - The file exists, but it is not a FIFO.
+/// * [`ENXIO`] - The file is a FIFO, but no process has it open for reading.
+///   Sleep for a while and try again.
+/// * Other OS errors not specific to opening FIFO files.
+///
+/// Opening a `Sender` from a FIFO file should look like this:
+///
+/// ```no_run
+/// use tokio::net::unix::pipe;
+/// use tokio::time::{self, Duration};
+///
+/// const FIFO_NAME: &str = "path/to/a/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
+/// // Wait for a reader to open the file.
+/// let tx = loop {
+///     match pipe::OpenOptions::new().open_sender(FIFO_NAME) {
+///         Ok(tx) => break tx,
+///         Err(e) if e.raw_os_error() == Some(libc::ENXIO) => {},
+///         Err(e) => return Err(e.into()),
+///     }
+///
+///     time::sleep(Duration::from_millis(50)).await;
+/// };
+/// # Ok(())
+/// # }
+/// ```
+///
+/// On Linux, it is possible to create a `Sender` without waiting in a sleeping
+/// loop. This is done by opening a named pipe in read-write access mode with
+/// `OpenOptions::read_write`. This way, a `Sender` can at the same time hold
+/// both a writing end and a reading end, and the latter allows to open a FIFO
+/// without [`ENXIO`] error since the pipe is open for reading as well.
+///
+/// `Sender` cannot be used to read from a pipe, so in practice the read access
+/// is only used when a FIFO is opened. However, using a `Sender` in read-write
+/// mode **may lead to lost data**, because written data will be dropped by the
+/// system as soon as all pipe ends are closed. To avoid lost data you have to
+/// make sure that a reading end has been opened before dropping a `Sender`.
+///
+/// Note that using read-write access mode with FIFO files is not defined by
+/// the POSIX standard and it is only guaranteed to work on Linux.
+///
+/// ```ignore
+/// use tokio::io::AsyncWriteExt;
+/// use tokio::net::unix::pipe;
+///
+/// const FIFO_NAME: &str = "path/to/a/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
+/// let mut tx = pipe::OpenOptions::new()
+///     .read_write(true)
+///     .open_sender(FIFO_NAME)?;
+///
+/// // Asynchronously write to the pipe before a reader.
+/// tx.write_all(b"hello world").await?;
+/// # Ok(())
+/// # }
+/// ```
+///
+/// [`ENXIO`]: https://docs.rs/libc/latest/libc/constant.ENXIO.html
+#[derive(Debug)]
+pub struct Sender {
+    io: PollEvented<mio_pipe::Sender>,
+}
+
+impl Sender {
+    fn from_mio(mio_tx: mio_pipe::Sender) -> io::Result<Sender> {
+        let io = PollEvented::new_with_interest(mio_tx, Interest::WRITABLE)?;
+        Ok(Sender { io })
+    }
+
+    /// Creates a new `Sender` from a [`File`].
+    ///
+    /// This function is intended to construct a pipe from a [`File`] representing
+    /// a special FIFO file. It will check if the file is a pipe and has write access,
+    /// set it in non-blocking mode and perform the conversion.
+    ///
+    /// # Errors
+    ///
+    /// Fails with `io::ErrorKind::InvalidInput` if the file is not a pipe or it
+    /// does not have write access. Also fails with any standard OS error if it occurs.
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn from_file(mut file: File) -> io::Result<Sender> {
+        if !is_fifo(&file)? {
+            return Err(io::Error::new(io::ErrorKind::InvalidInput, "not a pipe"));
+        }
+
+        let flags = get_file_flags(&file)?;
+        if has_write_access(flags) {
+            set_nonblocking(&mut file, flags)?;
+            Sender::from_file_unchecked(file)
+        } else {
+            Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "not in O_WRONLY or O_RDWR access mode",
+            ))
+        }
+    }
+
+    /// Creates a new `Sender` from a [`File`] without checking pipe properties.
+    ///
+    /// This function is intended to construct a pipe from a File representing
+    /// a special FIFO file. The conversion assumes nothing about the underlying
+    /// file; it is left up to the user to make sure it is opened with write access,
+    /// represents a pipe and is set in non-blocking mode.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::fs::OpenOptions;
+    /// use std::os::unix::fs::{FileTypeExt, OpenOptionsExt};
+    /// # use std::error::Error;
+    ///
+    /// const FIFO_NAME: &str = "path/to/a/fifo";
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let file = OpenOptions::new()
+    ///     .write(true)
+    ///     .custom_flags(libc::O_NONBLOCK)
+    ///     .open(FIFO_NAME)?;
+    /// if file.metadata()?.file_type().is_fifo() {
+    ///     let tx = pipe::Sender::from_file_unchecked(file)?;
+    ///     /* use the Sender */
+    /// }
+    /// # Ok(())
+    /// # }
+    /// ```
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn from_file_unchecked(file: File) -> io::Result<Sender> {
+        let raw_fd = file.into_raw_fd();
+        let mio_tx = unsafe { mio_pipe::Sender::from_raw_fd(raw_fd) };
+        Sender::from_mio(mio_tx)
+    }
+
+    /// Waits for any of the requested ready states.
+    ///
+    /// This function can be used instead of [`writable()`] to check the returned
+    /// ready set for [`Ready::WRITABLE`] and [`Ready::WRITE_CLOSED`] events.
+    ///
+    /// The function may complete without the pipe being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// [`writable()`]: Self::writable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        let event = self.io.registration().readiness(interest).await?;
+        Ok(event.ready)
+    }
+
+    /// Waits for the pipe to become writable.
+    ///
+    /// This function is equivalent to `ready(Interest::WRITABLE)` and is usually
+    /// paired with [`try_write()`].
+    ///
+    /// [`try_write()`]: Self::try_write
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a writing end of a fifo
+    ///     let tx = pipe::OpenOptions::new().open_sender("path/to/a/fifo")?;
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be writable
+    ///         tx.writable().await?;
+    ///
+    ///         // Try to write data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match tx.try_write(b"hello world") {
+    ///             Ok(n) => {
+    ///                 break;
+    ///             }
+    ///             Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    pub async fn writable(&self) -> io::Result<()> {
+        self.ready(Interest::WRITABLE).await?;
+        Ok(())
+    }
+
+    /// Polls for write readiness.
+    ///
+    /// If the pipe is not currently ready for writing, this method will
+    /// store a clone of the `Waker` from the provided `Context`. When the pipe
+    /// becomes ready for writing, `Waker::wake` will be called on the waker.
+    ///
+    /// Note that on multiple calls to `poll_write_ready` or `poll_write`, only
+    /// the `Waker` from the `Context` passed to the most recent call is
+    /// scheduled to receive a wakeup.
+    ///
+    /// This function is intended for cases where creating and pinning a future
+    /// via [`writable`] is not feasible. Where possible, using [`writable`] is
+    /// preferred, as this supports polling from multiple tasks at once.
+    ///
+    /// [`writable`]: Self::writable
+    ///
+    /// # Return value
+    ///
+    /// The function returns:
+    ///
+    /// * `Poll::Pending` if the pipe is not ready for writing.
+    /// * `Poll::Ready(Ok(()))` if the pipe is ready for writing.
+    /// * `Poll::Ready(Err(e))` if an error is encountered.
+    ///
+    /// # Errors
+    ///
+    /// This function may encounter any standard I/O error except `WouldBlock`.
+    pub fn poll_write_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.io.registration().poll_write_ready(cx).map_ok(|_| ())
+    }
+
+    /// Tries to write a buffer to the pipe, returning how many bytes were
+    /// written.
+    ///
+    /// The function will attempt to write the entire contents of `buf`, but
+    /// only part of the buffer may be written. If the length of `buf` is not
+    /// greater than `PIPE_BUF` (an OS constant, 4096 under Linux), then the
+    /// write is guaranteed to be atomic, i.e. either the entire content of
+    /// `buf` will be written or this method will fail with `WouldBlock`. There
+    /// is no such guarantee if `buf` is larger than `PIPE_BUF`.
+    ///
+    /// This function is usually paired with [`writable`].
+    ///
+    /// [`writable`]: Self::writable
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the pipe is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a writing end of a fifo
+    ///     let tx = pipe::OpenOptions::new().open_sender("path/to/a/fifo")?;
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be writable
+    ///         tx.writable().await?;
+    ///
+    ///         // Try to write data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match tx.try_write(b"hello world") {
+    ///             Ok(n) => {
+    ///                 break;
+    ///             }
+    ///             Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    pub fn try_write(&self, buf: &[u8]) -> io::Result<usize> {
+        self.io
+            .registration()
+            .try_io(Interest::WRITABLE, || (&*self.io).write(buf))
+    }
+
+    /// Tries to write several buffers to the pipe, returning how many bytes
+    /// were written.
+    ///
+    /// Data is written from each buffer in order, with the final buffer read
+    /// from possible being only partially consumed. This method behaves
+    /// equivalently to a single call to [`try_write()`] with concatenated
+    /// buffers.
+    ///
+    /// If the total length of buffers is not greater than `PIPE_BUF` (an OS
+    /// constant, 4096 under Linux), then the write is guaranteed to be atomic,
+    /// i.e. either the entire contents of buffers will be written or this
+    /// method will fail with `WouldBlock`. There is no such guarantee if the
+    /// total length of buffers is greater than `PIPE_BUF`.
+    ///
+    /// This function is usually paired with [`writable`].
+    ///
+    /// [`try_write()`]: Self::try_write()
+    /// [`writable`]: Self::writable
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the pipe is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a writing end of a fifo
+    ///     let tx = pipe::OpenOptions::new().open_sender("path/to/a/fifo")?;
+    ///
+    ///     let bufs = [io::IoSlice::new(b"hello "), io::IoSlice::new(b"world")];
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be writable
+    ///         tx.writable().await?;
+    ///
+    ///         // Try to write data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match tx.try_write_vectored(&bufs) {
+    ///             Ok(n) => {
+    ///                 break;
+    ///             }
+    ///             Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    pub fn try_write_vectored(&self, buf: &[io::IoSlice<'_>]) -> io::Result<usize> {
+        self.io
+            .registration()
+            .try_io(Interest::WRITABLE, || (&*self.io).write_vectored(buf))
+    }
+}
+
+impl AsyncWrite for Sender {
+    fn poll_write(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        self.io.poll_write(cx, buf)
+    }
+
+    fn poll_write_vectored(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        bufs: &[io::IoSlice<'_>],
+    ) -> Poll<io::Result<usize>> {
+        self.io.poll_write_vectored(cx, bufs)
+    }
+
+    fn is_write_vectored(&self) -> bool {
+        true
+    }
+
+    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<()>> {
+        Poll::Ready(Ok(()))
+    }
+}
+
+impl AsRawFd for Sender {
+    fn as_raw_fd(&self) -> RawFd {
+        self.io.as_raw_fd()
+    }
+}
+
+#[cfg(not(tokio_no_as_fd))]
+impl AsFd for Sender {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+    }
+}
+
+/// Reading end of a Unix pipe.
+///
+/// It can be constructed from a FIFO file with [`OpenOptions::open_receiver`].
+///
+/// # Examples
+///
+/// Receiving messages from a named pipe in a loop:
+///
+/// ```no_run
+/// use tokio::net::unix::pipe;
+/// use tokio::io::{self, AsyncReadExt};
+///
+/// const FIFO_NAME: &str = "path/to/a/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
+/// let mut rx = pipe::OpenOptions::new().open_receiver(FIFO_NAME)?;
+/// loop {
+///     let mut msg = vec![0; 256];
+///     match rx.read_exact(&mut msg).await {
+///         Ok(_) => {
+///             /* handle the message */
+///         }
+///         Err(e) if e.kind() == io::ErrorKind::UnexpectedEof => {
+///             // Writing end has been closed, we should reopen the pipe.
+///             rx = pipe::OpenOptions::new().open_receiver(FIFO_NAME)?;
+///         }
+///         Err(e) => return Err(e.into()),
+///     }
+/// }
+/// # }
+/// ```
+///
+/// On Linux, you can use a `Receiver` in read-write access mode to implement
+/// resilient reading from a named pipe. Unlike `Receiver` opened in read-only
+/// mode, read from a pipe in read-write mode will not fail with `UnexpectedEof`
+/// when the writing end is closed. This way, a `Receiver` can asynchronously
+/// wait for the next writer to open the pipe.
+///
+/// You should not use functions waiting for EOF such as [`read_to_end`] with
+/// a `Receiver` in read-write access mode, since it **may wait forever**.
+/// `Receiver` in this mode also holds an open writing end, which prevents
+/// receiving EOF.
+///
+/// To set the read-write access mode you can use `OpenOptions::read_write`.
+/// Note that using read-write access mode with FIFO files is not defined by
+/// the POSIX standard and it is only guaranteed to work on Linux.
+///
+/// ```ignore
+/// use tokio::net::unix::pipe;
+/// use tokio::io::AsyncReadExt;
+/// # use std::error::Error;
+///
+/// const FIFO_NAME: &str = "path/to/a/fifo";
+///
+/// # async fn dox() -> Result<(), Box<dyn Error>> {
+/// let mut rx = pipe::OpenOptions::new()
+///     .read_write(true)
+///     .open_receiver(FIFO_NAME)?;
+/// loop {
+///     let mut msg = vec![0; 256];
+///     rx.read_exact(&mut msg).await?;
+///     /* handle the message */
+/// }
+/// # }
+/// ```
+///
+/// [`read_to_end`]: crate::io::AsyncReadExt::read_to_end
+#[derive(Debug)]
+pub struct Receiver {
+    io: PollEvented<mio_pipe::Receiver>,
+}
+
+impl Receiver {
+    fn from_mio(mio_rx: mio_pipe::Receiver) -> io::Result<Receiver> {
+        let io = PollEvented::new_with_interest(mio_rx, Interest::READABLE)?;
+        Ok(Receiver { io })
+    }
+
+    /// Creates a new `Receiver` from a [`File`].
+    ///
+    /// This function is intended to construct a pipe from a [`File`] representing
+    /// a special FIFO file. It will check if the file is a pipe and has read access,
+    /// set it in non-blocking mode and perform the conversion.
+    ///
+    /// # Errors
+    ///
+    /// Fails with `io::ErrorKind::InvalidInput` if the file is not a pipe or it
+    /// does not have read access. Also fails with any standard OS error if it occurs.
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn from_file(mut file: File) -> io::Result<Receiver> {
+        if !is_fifo(&file)? {
+            return Err(io::Error::new(io::ErrorKind::InvalidInput, "not a pipe"));
+        }
+
+        let flags = get_file_flags(&file)?;
+        if has_read_access(flags) {
+            set_nonblocking(&mut file, flags)?;
+            Receiver::from_file_unchecked(file)
+        } else {
+            Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "not in O_RDONLY or O_RDWR access mode",
+            ))
+        }
+    }
+
+    /// Creates a new `Receiver` from a [`File`] without checking pipe properties.
+    ///
+    /// This function is intended to construct a pipe from a File representing
+    /// a special FIFO file. The conversion assumes nothing about the underlying
+    /// file; it is left up to the user to make sure it is opened with read access,
+    /// represents a pipe and is set in non-blocking mode.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::fs::OpenOptions;
+    /// use std::os::unix::fs::{FileTypeExt, OpenOptionsExt};
+    /// # use std::error::Error;
+    ///
+    /// const FIFO_NAME: &str = "path/to/a/fifo";
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let file = OpenOptions::new()
+    ///     .read(true)
+    ///     .custom_flags(libc::O_NONBLOCK)
+    ///     .open(FIFO_NAME)?;
+    /// if file.metadata()?.file_type().is_fifo() {
+    ///     let rx = pipe::Receiver::from_file_unchecked(file)?;
+    ///     /* use the Receiver */
+    /// }
+    /// # Ok(())
+    /// # }
+    /// ```
+    ///
+    /// # Panics
+    ///
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
+    ///
+    /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    pub fn from_file_unchecked(file: File) -> io::Result<Receiver> {
+        let raw_fd = file.into_raw_fd();
+        let mio_rx = unsafe { mio_pipe::Receiver::from_raw_fd(raw_fd) };
+        Receiver::from_mio(mio_rx)
+    }
+
+    /// Waits for any of the requested ready states.
+    ///
+    /// This function can be used instead of [`readable()`] to check the returned
+    /// ready set for [`Ready::READABLE`] and [`Ready::READ_CLOSED`] events.
+    ///
+    /// The function may complete without the pipe being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// [`readable()`]: Self::readable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        let event = self.io.registration().readiness(interest).await?;
+        Ok(event.ready)
+    }
+
+    /// Waits for the pipe to become readable.
+    ///
+    /// This function is equivalent to `ready(Interest::READABLE)` and is usually
+    /// paired with [`try_read()`].
+    ///
+    /// [`try_read()`]: Self::try_read()
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a reading end of a fifo
+    ///     let rx = pipe::OpenOptions::new().open_receiver("path/to/a/fifo")?;
+    ///
+    ///     let mut msg = vec![0; 1024];
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be readable
+    ///         rx.readable().await?;
+    ///
+    ///         // Try to read data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match rx.try_read(&mut msg) {
+    ///             Ok(n) => {
+    ///                 msg.truncate(n);
+    ///                 break;
+    ///             }
+    ///             Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     println!("GOT = {:?}", msg);
+    ///     Ok(())
+    /// }
+    /// ```
+    pub async fn readable(&self) -> io::Result<()> {
+        self.ready(Interest::READABLE).await?;
+        Ok(())
+    }
+
+    /// Polls for read readiness.
+    ///
+    /// If the pipe is not currently ready for reading, this method will
+    /// store a clone of the `Waker` from the provided `Context`. When the pipe
+    /// becomes ready for reading, `Waker::wake` will be called on the waker.
+    ///
+    /// Note that on multiple calls to `poll_read_ready` or `poll_read`, only
+    /// the `Waker` from the `Context` passed to the most recent call is
+    /// scheduled to receive a wakeup.
+    ///
+    /// This function is intended for cases where creating and pinning a future
+    /// via [`readable`] is not feasible. Where possible, using [`readable`] is
+    /// preferred, as this supports polling from multiple tasks at once.
+    ///
+    /// [`readable`]: Self::readable
+    ///
+    /// # Return value
+    ///
+    /// The function returns:
+    ///
+    /// * `Poll::Pending` if the pipe is not ready for reading.
+    /// * `Poll::Ready(Ok(()))` if the pipe is ready for reading.
+    /// * `Poll::Ready(Err(e))` if an error is encountered.
+    ///
+    /// # Errors
+    ///
+    /// This function may encounter any standard I/O error except `WouldBlock`.
+    pub fn poll_read_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        self.io.registration().poll_read_ready(cx).map_ok(|_| ())
+    }
+
+    /// Tries to read data from the pipe into the provided buffer, returning how
+    /// many bytes were read.
+    ///
+    /// Reads any pending data from the pipe but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read()` is non-blocking, the buffer does not have to be stored by
+    /// the async task and can exist entirely on the stack.
+    ///
+    /// Usually [`readable()`] is used with this function.
+    ///
+    /// [`readable()`]: Self::readable()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. If `n` is `0`, then it can indicate one of two scenarios:
+    ///
+    /// 1. The pipe's writing end is closed and will no longer write data.
+    /// 2. The specified buffer was 0 bytes in length.
+    ///
+    /// If the pipe is not ready to read data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a reading end of a fifo
+    ///     let rx = pipe::OpenOptions::new().open_receiver("path/to/a/fifo")?;
+    ///
+    ///     let mut msg = vec![0; 1024];
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be readable
+    ///         rx.readable().await?;
+    ///
+    ///         // Try to read data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match rx.try_read(&mut msg) {
+    ///             Ok(n) => {
+    ///                 msg.truncate(n);
+    ///                 break;
+    ///             }
+    ///             Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     println!("GOT = {:?}", msg);
+    ///     Ok(())
+    /// }
+    /// ```
+    pub fn try_read(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.io
+            .registration()
+            .try_io(Interest::READABLE, || (&*self.io).read(buf))
+    }
+
+    /// Tries to read data from the pipe into the provided buffers, returning
+    /// how many bytes were read.
+    ///
+    /// Data is copied to fill each buffer in order, with the final buffer
+    /// written to possibly being only partially filled. This method behaves
+    /// equivalently to a single call to [`try_read()`] with concatenated
+    /// buffers.
+    ///
+    /// Reads any pending data from the pipe but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read_vectored()` is non-blocking, the buffer does not have to be
+    /// stored by the async task and can exist entirely on the stack.
+    ///
+    /// Usually, [`readable()`] is used with this function.
+    ///
+    /// [`try_read()`]: Self::try_read()
+    /// [`readable()`]: Self::readable()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. `Ok(0)` indicates the pipe's writing end is
+    /// closed and will no longer write data. If the pipe is not ready to read
+    /// data `Err(io::ErrorKind::WouldBlock)` is returned.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::unix::pipe;
+    /// use std::io;
+    ///
+    /// #[tokio::main]
+    /// async fn main() -> io::Result<()> {
+    ///     // Open a reading end of a fifo
+    ///     let rx = pipe::OpenOptions::new().open_receiver("path/to/a/fifo")?;
+    ///
+    ///     loop {
+    ///         // Wait for the pipe to be readable
+    ///         rx.readable().await?;
+    ///
+    ///         // Creating the buffer **after** the `await` prevents it from
+    ///         // being stored in the async task.
+    ///         let mut buf_a = [0; 512];
+    ///         let mut buf_b = [0; 1024];
+    ///         let mut bufs = [
+    ///             io::IoSliceMut::new(&mut buf_a),
+    ///             io::IoSliceMut::new(&mut buf_b),
+    ///         ];
+    ///
+    ///         // Try to read data, this may still fail with `WouldBlock`
+    ///         // if the readiness event is a false positive.
+    ///         match rx.try_read_vectored(&mut bufs) {
+    ///             Ok(0) => break,
+    ///             Ok(n) => {
+    ///                 println!("read {} bytes", n);
+    ///             }
+    ///             Err(e) if e.kind() == io::ErrorKind::WouldBlock => {
+    ///                 continue;
+    ///             }
+    ///             Err(e) => {
+    ///                 return Err(e.into());
+    ///             }
+    ///         }
+    ///     }
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    pub fn try_read_vectored(&self, bufs: &mut [io::IoSliceMut<'_>]) -> io::Result<usize> {
+        self.io
+            .registration()
+            .try_io(Interest::READABLE, || (&*self.io).read_vectored(bufs))
+    }
+
+    cfg_io_util! {
+        /// Tries to read data from the pipe into the provided buffer, advancing the
+        /// buffer's internal cursor, returning how many bytes were read.
+        ///
+        /// Reads any pending data from the pipe but does not wait for new data
+        /// to arrive. On success, returns the number of bytes read. Because
+        /// `try_read_buf()` is non-blocking, the buffer does not have to be stored by
+        /// the async task and can exist entirely on the stack.
+        ///
+        /// Usually, [`readable()`] or [`ready()`] is used with this function.
+        ///
+        /// [`readable()`]: Self::readable
+        /// [`ready()`]: Self::ready
+        ///
+        /// # Return
+        ///
+        /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+        /// number of bytes read. `Ok(0)` indicates the pipe's writing end is
+        /// closed and will no longer write data. If the pipe is not ready to read
+        /// data `Err(io::ErrorKind::WouldBlock)` is returned.
+        ///
+        /// # Examples
+        ///
+        /// ```no_run
+        /// use tokio::net::unix::pipe;
+        /// use std::io;
+        ///
+        /// #[tokio::main]
+        /// async fn main() -> io::Result<()> {
+        ///     // Open a reading end of a fifo
+        ///     let rx = pipe::OpenOptions::new().open_receiver("path/to/a/fifo")?;
+        ///
+        ///     loop {
+        ///         // Wait for the pipe to be readable
+        ///         rx.readable().await?;
+        ///
+        ///         let mut buf = Vec::with_capacity(4096);
+        ///
+        ///         // Try to read data, this may still fail with `WouldBlock`
+        ///         // if the readiness event is a false positive.
+        ///         match rx.try_read_buf(&mut buf) {
+        ///             Ok(0) => break,
+        ///             Ok(n) => {
+        ///                 println!("read {} bytes", n);
+        ///             }
+        ///             Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
+        ///                 continue;
+        ///             }
+        ///             Err(e) => {
+        ///                 return Err(e.into());
+        ///             }
+        ///         }
+        ///     }
+        ///
+        ///     Ok(())
+        /// }
+        /// ```
+        pub fn try_read_buf<B: BufMut>(&self, buf: &mut B) -> io::Result<usize> {
+            self.io.registration().try_io(Interest::READABLE, || {
+                use std::io::Read;
+
+                let dst = buf.chunk_mut();
+                let dst =
+                    unsafe { &mut *(dst as *mut _ as *mut [std::mem::MaybeUninit<u8>] as *mut [u8]) };
+
+                // Safety: `mio_pipe::Receiver` uses a `std::fs::File` underneath,
+                // which correctly handles reads into uninitialized memory.
+                let n = (&*self.io).read(dst)?;
+
+                unsafe {
+                    buf.advance_mut(n);
+                }
+
+                Ok(n)
+            })
+        }
+    }
+}
+
+impl AsyncRead for Receiver {
+    fn poll_read(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+        buf: &mut ReadBuf<'_>,
+    ) -> Poll<io::Result<()>> {
+        // Safety: `mio_pipe::Receiver` uses a `std::fs::File` underneath,
+        // which correctly handles reads into uninitialized memory.
+        unsafe { self.io.poll_read(cx, buf) }
+    }
+}
+
+impl AsRawFd for Receiver {
+    fn as_raw_fd(&self) -> RawFd {
+        self.io.as_raw_fd()
+    }
+}
+
+#[cfg(not(tokio_no_as_fd))]
+impl AsFd for Receiver {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+    }
+}
+
+/// Checks if file is a FIFO
+fn is_fifo(file: &File) -> io::Result<bool> {
+    Ok(file.metadata()?.file_type().is_fifo())
+}
+
+/// Gets file descriptor's flags by fcntl.
+fn get_file_flags(file: &File) -> io::Result<libc::c_int> {
+    let fd = file.as_raw_fd();
+    let flags = unsafe { libc::fcntl(fd, libc::F_GETFL) };
+    if flags < 0 {
+        Err(io::Error::last_os_error())
+    } else {
+        Ok(flags)
+    }
+}
+
+/// Checks for O_RDONLY or O_RDWR access mode.
+fn has_read_access(flags: libc::c_int) -> bool {
+    let mode = flags & libc::O_ACCMODE;
+    mode == libc::O_RDONLY || mode == libc::O_RDWR
+}
+
+/// Checks for O_WRONLY or O_RDWR access mode.
+fn has_write_access(flags: libc::c_int) -> bool {
+    let mode = flags & libc::O_ACCMODE;
+    mode == libc::O_WRONLY || mode == libc::O_RDWR
+}
+
+/// Sets file's flags with O_NONBLOCK by fcntl.
+fn set_nonblocking(file: &mut File, current_flags: libc::c_int) -> io::Result<()> {
+    let fd = file.as_raw_fd();
+
+    let flags = current_flags | libc::O_NONBLOCK;
+
+    if flags != current_flags {
+        let ret = unsafe { libc::fcntl(fd, libc::F_SETFL, flags) };
+        if ret < 0 {
+            return Err(io::Error::last_os_error());
+        }
+    }
+
+    Ok(())
+}
diff --git a/vendor/tokio/src/net/unix/split.rs b/vendor/tokio/src/net/unix/split.rs
index 97214f7a7..6fc7067a7 100644
--- a/vendor/tokio/src/net/unix/split.rs
+++ b/vendor/tokio/src/net/unix/split.rs
@@ -8,14 +8,19 @@
 //! split has no associated overhead and enforces all invariants at the type
 //! level.
 
-use crate::io::{AsyncRead, AsyncWrite, ReadBuf};
+use crate::io::{AsyncRead, AsyncWrite, Interest, ReadBuf, Ready};
 use crate::net::UnixStream;
 
+use crate::net::unix::SocketAddr;
 use std::io;
 use std::net::Shutdown;
 use std::pin::Pin;
 use std::task::{Context, Poll};
 
+cfg_io_util! {
+    use bytes::BufMut;
+}
+
 /// Borrowed read half of a [`UnixStream`], created by [`split`].
 ///
 /// Reading from a `ReadHalf` is usually done using the convenience methods found on the
@@ -47,6 +52,232 @@ pub(crate) fn split(stream: &mut UnixStream) -> (ReadHalf<'_>, WriteHalf<'_>) {
     (ReadHalf(stream), WriteHalf(stream))
 }
 
+impl ReadHalf<'_> {
+    /// Wait for any of the requested ready states.
+    ///
+    /// This function is usually paired with [`try_read()`]. It can be used instead
+    /// of [`readable()`] to check the returned ready set for [`Ready::READABLE`]
+    /// and [`Ready::READ_CLOSED`] events.
+    ///
+    /// The function may complete without the socket being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// This function is equivalent to [`UnixStream::ready`].
+    ///
+    /// [`try_read()`]: Self::try_read
+    /// [`readable()`]: Self::readable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read or write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        self.0.ready(interest).await
+    }
+
+    /// Waits for the socket to become readable.
+    ///
+    /// This function is equivalent to `ready(Interest::READABLE)` and is usually
+    /// paired with `try_read()`.
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn readable(&self) -> io::Result<()> {
+        self.0.readable().await
+    }
+
+    /// Tries to read data from the stream into the provided buffer, returning how
+    /// many bytes were read.
+    ///
+    /// Receives any pending data from the socket but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read()` is non-blocking, the buffer does not have to be stored by
+    /// the async task and can exist entirely on the stack.
+    ///
+    /// Usually, [`readable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`readable()`]: Self::readable()
+    /// [`ready()`]: Self::ready()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. If `n` is `0`, then it can indicate one of two scenarios:
+    ///
+    /// 1. The stream's read half is closed and will no longer yield data.
+    /// 2. The specified buffer was 0 bytes in length.
+    ///
+    /// If the stream is not ready to read data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_read(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.0.try_read(buf)
+    }
+
+    cfg_io_util! {
+        /// Tries to read data from the stream into the provided buffer, advancing the
+        /// buffer's internal cursor, returning how many bytes were read.
+        ///
+        /// Receives any pending data from the socket but does not wait for new data
+        /// to arrive. On success, returns the number of bytes read. Because
+        /// `try_read_buf()` is non-blocking, the buffer does not have to be stored by
+        /// the async task and can exist entirely on the stack.
+        ///
+        /// Usually, [`readable()`] or [`ready()`] is used with this function.
+        ///
+        /// [`readable()`]: Self::readable()
+        /// [`ready()`]: Self::ready()
+        ///
+        /// # Return
+        ///
+        /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+        /// number of bytes read. `Ok(0)` indicates the stream's read half is closed
+        /// and will no longer yield data. If the stream is not ready to read data
+        pub fn try_read_buf<B: BufMut>(&self, buf: &mut B) -> io::Result<usize> {
+            self.0.try_read_buf(buf)
+        }
+    }
+
+    /// Tries to read data from the stream into the provided buffers, returning
+    /// how many bytes were read.
+    ///
+    /// Data is copied to fill each buffer in order, with the final buffer
+    /// written to possibly being only partially filled. This method behaves
+    /// equivalently to a single call to [`try_read()`] with concatenated
+    /// buffers.
+    ///
+    /// Receives any pending data from the socket but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read_vectored()` is non-blocking, the buffer does not have to be
+    /// stored by the async task and can exist entirely on the stack.
+    ///
+    /// Usually, [`readable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`try_read()`]: Self::try_read()
+    /// [`readable()`]: Self::readable()
+    /// [`ready()`]: Self::ready()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. `Ok(0)` indicates the stream's read half is closed
+    /// and will no longer yield data. If the stream is not ready to read data
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_read_vectored(&self, bufs: &mut [io::IoSliceMut<'_>]) -> io::Result<usize> {
+        self.0.try_read_vectored(bufs)
+    }
+
+    /// Returns the socket address of the remote half of this connection.
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.0.peer_addr()
+    }
+
+    /// Returns the socket address of the local half of this connection.
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.0.local_addr()
+    }
+}
+
+impl WriteHalf<'_> {
+    /// Waits for any of the requested ready states.
+    ///
+    /// This function is usually paired with [`try_write()`]. It can be used instead
+    /// of [`writable()`] to check the returned ready set for [`Ready::WRITABLE`]
+    /// and [`Ready::WRITE_CLOSED`] events.
+    ///
+    /// The function may complete without the socket being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// This function is equivalent to [`UnixStream::ready`].
+    ///
+    /// [`try_write()`]: Self::try_write
+    /// [`writable()`]: Self::writable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read or write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        self.0.ready(interest).await
+    }
+
+    /// Waits for the socket to become writable.
+    ///
+    /// This function is equivalent to `ready(Interest::WRITABLE)` and is usually
+    /// paired with `try_write()`.
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn writable(&self) -> io::Result<()> {
+        self.0.writable().await
+    }
+
+    /// Tries to write a buffer to the stream, returning how many bytes were
+    /// written.
+    ///
+    /// The function will attempt to write the entire contents of `buf`, but
+    /// only part of the buffer may be written.
+    ///
+    /// This function is usually paired with `writable()`.
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the stream is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_write(&self, buf: &[u8]) -> io::Result<usize> {
+        self.0.try_write(buf)
+    }
+
+    /// Tries to write several buffers to the stream, returning how many bytes
+    /// were written.
+    ///
+    /// Data is written from each buffer in order, with the final buffer read
+    /// from possible being only partially consumed. This method behaves
+    /// equivalently to a single call to [`try_write()`] with concatenated
+    /// buffers.
+    ///
+    /// This function is usually paired with `writable()`.
+    ///
+    /// [`try_write()`]: Self::try_write()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the stream is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_write_vectored(&self, buf: &[io::IoSlice<'_>]) -> io::Result<usize> {
+        self.0.try_write_vectored(buf)
+    }
+
+    /// Returns the socket address of the remote half of this connection.
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.0.peer_addr()
+    }
+
+    /// Returns the socket address of the local half of this connection.
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.0.local_addr()
+    }
+}
+
 impl AsyncRead for ReadHalf<'_> {
     fn poll_read(
         self: Pin<&mut Self>,
diff --git a/vendor/tokio/src/net/unix/split_owned.rs b/vendor/tokio/src/net/unix/split_owned.rs
index 3d6ac6a7e..d1c6f93de 100644
--- a/vendor/tokio/src/net/unix/split_owned.rs
+++ b/vendor/tokio/src/net/unix/split_owned.rs
@@ -8,9 +8,10 @@
 //! split has no associated overhead and enforces all invariants at the type
 //! level.
 
-use crate::io::{AsyncRead, AsyncWrite, ReadBuf};
+use crate::io::{AsyncRead, AsyncWrite, Interest, ReadBuf, Ready};
 use crate::net::UnixStream;
 
+use crate::net::unix::SocketAddr;
 use std::error::Error;
 use std::net::Shutdown;
 use std::pin::Pin;
@@ -18,6 +19,10 @@ use std::sync::Arc;
 use std::task::{Context, Poll};
 use std::{fmt, io};
 
+cfg_io_util! {
+    use bytes::BufMut;
+}
+
 /// Owned read half of a [`UnixStream`], created by [`into_split`].
 ///
 /// Reading from an `OwnedReadHalf` is usually done using the convenience methods found
@@ -102,6 +107,139 @@ impl OwnedReadHalf {
     pub fn reunite(self, other: OwnedWriteHalf) -> Result<UnixStream, ReuniteError> {
         reunite(self, other)
     }
+
+    /// Waits for any of the requested ready states.
+    ///
+    /// This function is usually paired with [`try_read()`]. It can be used instead
+    /// of [`readable()`] to check the returned ready set for [`Ready::READABLE`]
+    /// and [`Ready::READ_CLOSED`] events.
+    ///
+    /// The function may complete without the socket being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// This function is equivalent to [`UnixStream::ready`].
+    ///
+    /// [`try_read()`]: Self::try_read
+    /// [`readable()`]: Self::readable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read or write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        self.inner.ready(interest).await
+    }
+
+    /// Waits for the socket to become readable.
+    ///
+    /// This function is equivalent to `ready(Interest::READABLE)` and is usually
+    /// paired with `try_read()`.
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn readable(&self) -> io::Result<()> {
+        self.inner.readable().await
+    }
+
+    /// Tries to read data from the stream into the provided buffer, returning how
+    /// many bytes were read.
+    ///
+    /// Receives any pending data from the socket but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read()` is non-blocking, the buffer does not have to be stored by
+    /// the async task and can exist entirely on the stack.
+    ///
+    /// Usually, [`readable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`readable()`]: Self::readable()
+    /// [`ready()`]: Self::ready()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. If `n` is `0`, then it can indicate one of two scenarios:
+    ///
+    /// 1. The stream's read half is closed and will no longer yield data.
+    /// 2. The specified buffer was 0 bytes in length.
+    ///
+    /// If the stream is not ready to read data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_read(&self, buf: &mut [u8]) -> io::Result<usize> {
+        self.inner.try_read(buf)
+    }
+
+    cfg_io_util! {
+        /// Tries to read data from the stream into the provided buffer, advancing the
+        /// buffer's internal cursor, returning how many bytes were read.
+        ///
+        /// Receives any pending data from the socket but does not wait for new data
+        /// to arrive. On success, returns the number of bytes read. Because
+        /// `try_read_buf()` is non-blocking, the buffer does not have to be stored by
+        /// the async task and can exist entirely on the stack.
+        ///
+        /// Usually, [`readable()`] or [`ready()`] is used with this function.
+        ///
+        /// [`readable()`]: Self::readable()
+        /// [`ready()`]: Self::ready()
+        ///
+        /// # Return
+        ///
+        /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+        /// number of bytes read. `Ok(0)` indicates the stream's read half is closed
+        /// and will no longer yield data. If the stream is not ready to read data
+        /// `Err(io::ErrorKind::WouldBlock)` is returned.
+        pub fn try_read_buf<B: BufMut>(&self, buf: &mut B) -> io::Result<usize> {
+            self.inner.try_read_buf(buf)
+        }
+    }
+
+    /// Tries to read data from the stream into the provided buffers, returning
+    /// how many bytes were read.
+    ///
+    /// Data is copied to fill each buffer in order, with the final buffer
+    /// written to possibly being only partially filled. This method behaves
+    /// equivalently to a single call to [`try_read()`] with concatenated
+    /// buffers.
+    ///
+    /// Receives any pending data from the socket but does not wait for new data
+    /// to arrive. On success, returns the number of bytes read. Because
+    /// `try_read_vectored()` is non-blocking, the buffer does not have to be
+    /// stored by the async task and can exist entirely on the stack.
+    ///
+    /// Usually, [`readable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`try_read()`]: Self::try_read()
+    /// [`readable()`]: Self::readable()
+    /// [`ready()`]: Self::ready()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully read, `Ok(n)` is returned, where `n` is the
+    /// number of bytes read. `Ok(0)` indicates the stream's read half is closed
+    /// and will no longer yield data. If the stream is not ready to read data
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_read_vectored(&self, bufs: &mut [io::IoSliceMut<'_>]) -> io::Result<usize> {
+        self.inner.try_read_vectored(bufs)
+    }
+
+    /// Returns the socket address of the remote half of this connection.
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.inner.peer_addr()
+    }
+
+    /// Returns the socket address of the local half of this connection.
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.inner.local_addr()
+    }
 }
 
 impl AsyncRead for OwnedReadHalf {
@@ -124,13 +262,103 @@ impl OwnedWriteHalf {
         reunite(other, self)
     }
 
-    /// Destroy the write half, but don't close the write half of the stream
+    /// Destroys the write half, but don't close the write half of the stream
     /// until the read half is dropped. If the read half has already been
     /// dropped, this closes the stream.
     pub fn forget(mut self) {
         self.shutdown_on_drop = false;
         drop(self);
     }
+
+    /// Waits for any of the requested ready states.
+    ///
+    /// This function is usually paired with [`try_write()`]. It can be used instead
+    /// of [`writable()`] to check the returned ready set for [`Ready::WRITABLE`]
+    /// and [`Ready::WRITE_CLOSED`] events.
+    ///
+    /// The function may complete without the socket being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
+    /// This function is equivalent to [`UnixStream::ready`].
+    ///
+    /// [`try_write()`]: Self::try_write
+    /// [`writable()`]: Self::writable
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to read or write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn ready(&self, interest: Interest) -> io::Result<Ready> {
+        self.inner.ready(interest).await
+    }
+
+    /// Waits for the socket to become writable.
+    ///
+    /// This function is equivalent to `ready(Interest::WRITABLE)` and is usually
+    /// paired with `try_write()`.
+    ///
+    /// # Cancel safety
+    ///
+    /// This method is cancel safe. Once a readiness event occurs, the method
+    /// will continue to return immediately until the readiness event is
+    /// consumed by an attempt to write that fails with `WouldBlock` or
+    /// `Poll::Pending`.
+    pub async fn writable(&self) -> io::Result<()> {
+        self.inner.writable().await
+    }
+
+    /// Tries to write a buffer to the stream, returning how many bytes were
+    /// written.
+    ///
+    /// The function will attempt to write the entire contents of `buf`, but
+    /// only part of the buffer may be written.
+    ///
+    /// This function is usually paired with `writable()`.
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the stream is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_write(&self, buf: &[u8]) -> io::Result<usize> {
+        self.inner.try_write(buf)
+    }
+
+    /// Tries to write several buffers to the stream, returning how many bytes
+    /// were written.
+    ///
+    /// Data is written from each buffer in order, with the final buffer read
+    /// from possible being only partially consumed. This method behaves
+    /// equivalently to a single call to [`try_write()`] with concatenated
+    /// buffers.
+    ///
+    /// This function is usually paired with `writable()`.
+    ///
+    /// [`try_write()`]: Self::try_write()
+    ///
+    /// # Return
+    ///
+    /// If data is successfully written, `Ok(n)` is returned, where `n` is the
+    /// number of bytes written. If the stream is not ready to write data,
+    /// `Err(io::ErrorKind::WouldBlock)` is returned.
+    pub fn try_write_vectored(&self, buf: &[io::IoSlice<'_>]) -> io::Result<usize> {
+        self.inner.try_write_vectored(buf)
+    }
+
+    /// Returns the socket address of the remote half of this connection.
+    pub fn peer_addr(&self) -> io::Result<SocketAddr> {
+        self.inner.peer_addr()
+    }
+
+    /// Returns the socket address of the local half of this connection.
+    pub fn local_addr(&self) -> io::Result<SocketAddr> {
+        self.inner.local_addr()
+    }
 }
 
 impl Drop for OwnedWriteHalf {
@@ -180,12 +408,12 @@ impl AsyncWrite for OwnedWriteHalf {
 
 impl AsRef<UnixStream> for OwnedReadHalf {
     fn as_ref(&self) -> &UnixStream {
-        &*self.inner
+        &self.inner
     }
 }
 
 impl AsRef<UnixStream> for OwnedWriteHalf {
     fn as_ref(&self) -> &UnixStream {
-        &*self.inner
+        &self.inner
     }
 }
diff --git a/vendor/tokio/src/net/unix/stream.rs b/vendor/tokio/src/net/unix/stream.rs
index 4baac6062..201645ba1 100644
--- a/vendor/tokio/src/net/unix/stream.rs
+++ b/vendor/tokio/src/net/unix/stream.rs
@@ -5,10 +5,11 @@ use crate::net::unix::split_owned::{split_owned, OwnedReadHalf, OwnedWriteHalf};
 use crate::net::unix::ucred::{self, UCred};
 use crate::net::unix::SocketAddr;
 
-use std::convert::TryFrom;
 use std::fmt;
 use std::io::{self, Read, Write};
 use std::net::Shutdown;
+#[cfg(not(tokio_no_as_fd))]
+use std::os::unix::io::{AsFd, BorrowedFd};
 use std::os::unix::io::{AsRawFd, FromRawFd, IntoRawFd, RawFd};
 use std::os::unix::net;
 use std::path::Path;
@@ -22,8 +23,8 @@ cfg_io_util! {
 cfg_net_unix! {
     /// 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
+    /// This socket can be connected directly with [`UnixStream::connect`] or accepted
+    /// from a listener with [`UnixListener::accept`]. Additionally, a pair of
     /// anonymous Unix sockets can be created with `UnixStream::pair`.
     ///
     /// To shut down the stream in the write direction, you can call the
@@ -32,6 +33,8 @@ cfg_net_unix! {
     /// the stream in one direction.
     ///
     /// [`shutdown()`]: fn@crate::io::AsyncWriteExt::shutdown
+    /// [`UnixListener::accept`]: crate::net::UnixListener::accept
+    #[cfg_attr(docsrs, doc(alias = "uds"))]
     pub struct UnixStream {
         io: PollEvented<mio::net::UnixStream>,
     }
@@ -59,12 +62,18 @@ impl UnixStream {
         Ok(stream)
     }
 
-    /// Wait for any of the requested ready states.
+    /// Waits for any of the requested ready states.
     ///
     /// This function is usually paired with `try_read()` or `try_write()`. It
     /// can be used to concurrently read / write to the same socket on a single
     /// task without splitting the socket.
     ///
+    /// The function may complete without the socket being ready. This is a
+    /// false-positive and attempting an operation will return with
+    /// `io::ErrorKind::WouldBlock`. The function can also return with an empty
+    /// [`Ready`] set, so you should always check the returned value and possibly
+    /// wait again if the requested states are not set.
+    ///
     /// # Cancel safety
     ///
     /// This method is cancel safe. Once a readiness event occurs, the method
@@ -133,7 +142,7 @@ impl UnixStream {
         Ok(event.ready)
     }
 
-    /// Wait for the socket to become readable.
+    /// Waits for the socket to become readable.
     ///
     /// This function is equivalent to `ready(Interest::READABLE)` and is usually
     /// paired with `try_read()`.
@@ -239,8 +248,12 @@ impl UnixStream {
     /// # Return
     ///
     /// If data is successfully read, `Ok(n)` is returned, where `n` is the
-    /// number of bytes read. `Ok(0)` indicates the stream's read half is closed
-    /// and will no longer yield data. If the stream is not ready to read data
+    /// number of bytes read. If `n` is `0`, then it can indicate one of two scenarios:
+    ///
+    /// 1. The stream's read half is closed and will no longer yield data.
+    /// 2. The specified buffer was 0 bytes in length.
+    ///
+    /// If the stream is not ready to read data,
     /// `Err(io::ErrorKind::WouldBlock)` is returned.
     ///
     /// # Examples
@@ -290,7 +303,7 @@ impl UnixStream {
             .try_io(Interest::READABLE, || (&*self.io).read(buf))
     }
 
-    /// Try to read data from the stream into the provided buffers, returning
+    /// Tries to read data from the stream into the provided buffers, returning
     /// how many bytes were read.
     ///
     /// Data is copied to fill each buffer in order, with the final buffer
@@ -369,7 +382,7 @@ impl UnixStream {
     }
 
     cfg_io_util! {
-        /// Try to read data from the stream into the provided buffer, advancing the
+        /// Tries to read data from the stream into the provided buffer, advancing the
         /// buffer's internal cursor, returning how many bytes were read.
         ///
         /// Receives any pending data from the socket but does not wait for new data
@@ -449,7 +462,7 @@ impl UnixStream {
         }
     }
 
-    /// Wait for the socket to become writable.
+    /// Waits for the socket to become writable.
     ///
     /// This function is equivalent to `ready(Interest::WRITABLE)` and is usually
     /// paired with `try_write()`.
@@ -535,7 +548,7 @@ impl UnixStream {
         self.io.registration().poll_write_ready(cx).map_ok(|_| ())
     }
 
-    /// Try to write a buffer to the stream, returning how many bytes were
+    /// Tries to write a buffer to the stream, returning how many bytes were
     /// written.
     ///
     /// The function will attempt to write the entire contents of `buf`, but
@@ -591,7 +604,7 @@ impl UnixStream {
             .try_io(Interest::WRITABLE, || (&*self.io).write(buf))
     }
 
-    /// Try to write several buffers to the stream, returning how many bytes
+    /// Tries to write several buffers to the stream, returning how many bytes
     /// were written.
     ///
     /// Data is written from each buffer in order, with the final buffer read
@@ -653,20 +666,122 @@ impl UnixStream {
             .try_io(Interest::WRITABLE, || (&*self.io).write_vectored(buf))
     }
 
+    /// Tries to read or write from the socket using a user-provided IO operation.
+    ///
+    /// If the socket is ready, the provided closure is called. The closure
+    /// should attempt to perform IO operation on the socket by manually
+    /// calling the appropriate syscall. If the operation fails because the
+    /// socket is not actually ready, then the closure should return a
+    /// `WouldBlock` error and the readiness flag is cleared. The return value
+    /// of the closure is then returned by `try_io`.
+    ///
+    /// If the socket is not ready, then the closure is not called
+    /// and a `WouldBlock` error is returned.
+    ///
+    /// The closure should only return a `WouldBlock` error if it has performed
+    /// an IO operation on the socket that failed due to the socket not being
+    /// ready. Returning a `WouldBlock` error in any other situation will
+    /// incorrectly clear the readiness flag, which can cause the socket to
+    /// behave incorrectly.
+    ///
+    /// The closure should not perform the IO operation using any of the methods
+    /// defined on the Tokio `UnixStream` type, as this will mess with the
+    /// readiness flag and can cause the socket to behave incorrectly.
+    ///
+    /// This method is not intended to be used with combined interests.
+    /// The closure should perform only one type of IO operation, so it should not
+    /// require more than one ready state. This method may panic or sleep forever
+    /// if it is called with a combined interest.
+    ///
+    /// Usually, [`readable()`], [`writable()`] or [`ready()`] is used with this function.
+    ///
+    /// [`readable()`]: UnixStream::readable()
+    /// [`writable()`]: UnixStream::writable()
+    /// [`ready()`]: UnixStream::ready()
+    pub fn try_io<R>(
+        &self,
+        interest: Interest,
+        f: impl FnOnce() -> io::Result<R>,
+    ) -> io::Result<R> {
+        self.io
+            .registration()
+            .try_io(interest, || self.io.try_io(f))
+    }
+
+    /// Reads or writes from the socket using a user-provided IO operation.
+    ///
+    /// The readiness of the socket is awaited and when the socket is ready,
+    /// the provided closure is called. The closure should attempt to perform
+    /// IO operation on the socket by manually calling the appropriate syscall.
+    /// If the operation fails because the socket is not actually ready,
+    /// then the closure should return a `WouldBlock` error. In such case the
+    /// readiness flag is cleared and the socket readiness is awaited again.
+    /// This loop is repeated until the closure returns an `Ok` or an error
+    /// other than `WouldBlock`.
+    ///
+    /// The closure should only return a `WouldBlock` error if it has performed
+    /// an IO operation on the socket that failed due to the socket not being
+    /// ready. Returning a `WouldBlock` error in any other situation will
+    /// incorrectly clear the readiness flag, which can cause the socket to
+    /// behave incorrectly.
+    ///
+    /// The closure should not perform the IO operation using any of the methods
+    /// defined on the Tokio `UnixStream` type, as this will mess with the
+    /// readiness flag and can cause the socket to behave incorrectly.
+    ///
+    /// This method is not intended to be used with combined interests.
+    /// The closure should perform only one type of IO operation, so it should not
+    /// require more than one ready state. This method may panic or sleep forever
+    /// if it is called with a combined interest.
+    pub async fn async_io<R>(
+        &self,
+        interest: Interest,
+        mut f: impl FnMut() -> io::Result<R>,
+    ) -> io::Result<R> {
+        self.io
+            .registration()
+            .async_io(interest, || self.io.try_io(&mut f))
+            .await
+    }
+
     /// Creates new `UnixStream` from a `std::os::unix::net::UnixStream`.
     ///
     /// This function is intended to be used to wrap a UnixStream from the
-    /// standard library in the Tokio equivalent. The conversion assumes
-    /// nothing about the underlying stream; it is left up to the user to set
-    /// it in non-blocking mode.
+    /// standard library in the Tokio equivalent.
+    ///
+    /// # Notes
+    ///
+    /// The caller is responsible for ensuring that the stream is in
+    /// non-blocking mode. Otherwise all I/O operations on the stream
+    /// will block the thread, which will cause unexpected behavior.
+    /// Non-blocking mode can be set using [`set_nonblocking`].
+    ///
+    /// [`set_nonblocking`]: std::os::unix::net::UnixStream::set_nonblocking
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::UnixStream;
+    /// use std::os::unix::net::UnixStream as StdUnixStream;
+    /// # use std::error::Error;
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn Error>> {
+    /// let std_stream = StdUnixStream::connect("/path/to/the/socket")?;
+    /// std_stream.set_nonblocking(true)?;
+    /// let stream = UnixStream::from_std(std_stream)?;
+    /// # Ok(())
+    /// # }
+    /// ```
     ///
     /// # Panics
     ///
-    /// This function panics if thread-local runtime is not set.
+    /// This function panics if it is not called from within a runtime with
+    /// IO enabled.
     ///
     /// 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 [`Runtime::enter`](crate::runtime::Runtime::enter) function.
+    #[track_caller]
     pub fn from_std(stream: net::UnixStream) -> io::Result<UnixStream> {
         let stream = mio::net::UnixStream::from_std(stream);
         let io = PollEvented::new(stream)?;
@@ -674,7 +789,7 @@ impl UnixStream {
         Ok(UnixStream { io })
     }
 
-    /// Turn a [`tokio::net::UnixStream`] into a [`std::os::unix::net::UnixStream`].
+    /// Turns a [`tokio::net::UnixStream`] into a [`std::os::unix::net::UnixStream`].
     ///
     /// The returned [`std::os::unix::net::UnixStream`] will have nonblocking
     /// mode set as `true`.  Use [`set_nonblocking`] to change the blocking
@@ -738,11 +853,41 @@ impl UnixStream {
     }
 
     /// Returns the socket address of the local half of this connection.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::UnixStream;
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
+    /// let dir = tempfile::tempdir().unwrap();
+    /// let bind_path = dir.path().join("bind_path");
+    /// let stream = UnixStream::connect(bind_path).await?;
+    ///
+    /// println!("{:?}", stream.local_addr()?);
+    /// # Ok(())
+    /// # }
+    /// ```
     pub fn local_addr(&self) -> io::Result<SocketAddr> {
         self.io.local_addr().map(SocketAddr)
     }
 
     /// Returns the socket address of the remote half of this connection.
+    ///
+    /// # Examples
+    ///
+    /// ```no_run
+    /// use tokio::net::UnixStream;
+    ///
+    /// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
+    /// let dir = tempfile::tempdir().unwrap();
+    /// let bind_path = dir.path().join("bind_path");
+    /// let stream = UnixStream::connect(bind_path).await?;
+    ///
+    /// println!("{:?}", stream.peer_addr()?);
+    /// # Ok(())
+    /// # }
+    /// ```
     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
         self.io.peer_addr().map(SocketAddr)
     }
@@ -769,7 +914,7 @@ impl UnixStream {
     // These lifetime markers also appear in the generated documentation, and make
     // it more clear that this is a *borrowed* split.
     #[allow(clippy::needless_lifetimes)]
-    /// Split a `UnixStream` into a read half and a write half, which can be used
+    /// Splits a `UnixStream` into a read half and a write half, which can be used
     /// to read and write the stream concurrently.
     ///
     /// This method is more efficient than [`into_split`], but the halves cannot be
@@ -893,3 +1038,10 @@ impl AsRawFd for UnixStream {
         self.io.as_raw_fd()
     }
 }
+
+#[cfg(not(tokio_no_as_fd))]
+impl AsFd for UnixStream {
+    fn as_fd(&self) -> BorrowedFd<'_> {
+        unsafe { BorrowedFd::borrow_raw(self.as_raw_fd()) }
+    }
+}
diff --git a/vendor/tokio/src/net/unix/ucred.rs b/vendor/tokio/src/net/unix/ucred.rs
index 6310183d7..edfab08ab 100644
--- a/vendor/tokio/src/net/unix/ucred.rs
+++ b/vendor/tokio/src/net/unix/ucred.rs
@@ -1,24 +1,24 @@
-use libc::{gid_t, pid_t, uid_t};
+use crate::net::unix;
 
-/// Credentials of a process
+/// Credentials of a process.
 #[derive(Copy, Clone, Eq, PartialEq, Hash, Debug)]
 pub struct UCred {
-    /// PID (process ID) of the process
-    pid: Option<pid_t>,
-    /// UID (user ID) of the process
-    uid: uid_t,
-    /// GID (group ID) of the process
-    gid: gid_t,
+    /// PID (process ID) of the process.
+    pid: Option<unix::pid_t>,
+    /// UID (user ID) of the process.
+    uid: unix::uid_t,
+    /// GID (group ID) of the process.
+    gid: unix::gid_t,
 }
 
 impl UCred {
     /// Gets UID (user ID) of the process.
-    pub fn uid(&self) -> uid_t {
+    pub fn uid(&self) -> unix::uid_t {
         self.uid
     }
 
     /// Gets GID (group ID) of the process.
-    pub fn gid(&self) -> gid_t {
+    pub fn gid(&self) -> unix::gid_t {
         self.gid
     }
 
@@ -26,20 +26,23 @@ impl UCred {
     ///
     /// This is only implemented under Linux, Android, iOS, macOS, Solaris and
     /// Illumos. On other platforms this will always return `None`.
-    pub fn pid(&self) -> Option<pid_t> {
+    pub fn pid(&self) -> Option<unix::pid_t> {
         self.pid
     }
 }
 
-#[cfg(any(target_os = "linux", target_os = "android"))]
-pub(crate) use self::impl_linux::get_peer_cred;
-
 #[cfg(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "netbsd",
+    target_os = "linux",
+    target_os = "redox",
+    target_os = "android",
     target_os = "openbsd"
 ))]
+pub(crate) use self::impl_linux::get_peer_cred;
+
+#[cfg(any(target_os = "netbsd"))]
+pub(crate) use self::impl_netbsd::get_peer_cred;
+
+#[cfg(any(target_os = "dragonfly", target_os = "freebsd"))]
 pub(crate) use self::impl_bsd::get_peer_cred;
 
 #[cfg(any(target_os = "macos", target_os = "ios"))]
@@ -48,13 +51,24 @@ pub(crate) use self::impl_macos::get_peer_cred;
 #[cfg(any(target_os = "solaris", target_os = "illumos"))]
 pub(crate) use self::impl_solaris::get_peer_cred;
 
-#[cfg(any(target_os = "linux", target_os = "android"))]
+#[cfg(target_os = "aix")]
+pub(crate) use self::impl_aix::get_peer_cred;
+
+#[cfg(any(
+    target_os = "linux",
+    target_os = "redox",
+    target_os = "android",
+    target_os = "openbsd"
+))]
 pub(crate) mod impl_linux {
-    use crate::net::unix::UnixStream;
+    use crate::net::unix::{self, UnixStream};
 
     use libc::{c_void, getsockopt, socklen_t, SOL_SOCKET, SO_PEERCRED};
     use std::{io, mem};
 
+    #[cfg(target_os = "openbsd")]
+    use libc::sockpeercred as ucred;
+    #[cfg(any(target_os = "linux", target_os = "redox", target_os = "android"))]
     use libc::ucred;
 
     pub(crate) fn get_peer_cred(sock: &UnixStream) -> io::Result<super::UCred> {
@@ -86,9 +100,9 @@ pub(crate) mod impl_linux {
             );
             if ret == 0 && ucred_size as usize == mem::size_of::<ucred>() {
                 Ok(super::UCred {
-                    uid: ucred.uid,
-                    gid: ucred.gid,
-                    pid: Some(ucred.pid),
+                    uid: ucred.uid as unix::uid_t,
+                    gid: ucred.gid as unix::gid_t,
+                    pid: Some(ucred.pid as unix::pid_t),
                 })
             } else {
                 Err(io::Error::last_os_error())
@@ -97,14 +111,51 @@ pub(crate) mod impl_linux {
     }
 }
 
-#[cfg(any(
-    target_os = "dragonfly",
-    target_os = "freebsd",
-    target_os = "netbsd",
-    target_os = "openbsd"
-))]
+#[cfg(any(target_os = "netbsd"))]
+pub(crate) mod impl_netbsd {
+    use crate::net::unix::{self, UnixStream};
+
+    use libc::{c_void, getsockopt, socklen_t, unpcbid, LOCAL_PEEREID, SOL_SOCKET};
+    use std::io;
+    use std::mem::size_of;
+    use std::os::unix::io::AsRawFd;
+
+    pub(crate) fn get_peer_cred(sock: &UnixStream) -> io::Result<super::UCred> {
+        unsafe {
+            let raw_fd = sock.as_raw_fd();
+
+            let mut unpcbid = unpcbid {
+                unp_pid: 0,
+                unp_euid: 0,
+                unp_egid: 0,
+            };
+
+            let unpcbid_size = size_of::<unpcbid>();
+            let mut unpcbid_size = unpcbid_size as socklen_t;
+
+            let ret = getsockopt(
+                raw_fd,
+                SOL_SOCKET,
+                LOCAL_PEEREID,
+                &mut unpcbid as *mut unpcbid as *mut c_void,
+                &mut unpcbid_size,
+            );
+            if ret == 0 && unpcbid_size as usize == size_of::<unpcbid>() {
+                Ok(super::UCred {
+                    uid: unpcbid.unp_euid as unix::uid_t,
+                    gid: unpcbid.unp_egid as unix::gid_t,
+                    pid: Some(unpcbid.unp_pid as unix::pid_t),
+                })
+            } else {
+                Err(io::Error::last_os_error())
+            }
+        }
+    }
+}
+
+#[cfg(any(target_os = "dragonfly", target_os = "freebsd"))]
 pub(crate) mod impl_bsd {
-    use crate::net::unix::UnixStream;
+    use crate::net::unix::{self, UnixStream};
 
     use libc::getpeereid;
     use std::io;
@@ -122,8 +173,8 @@ pub(crate) mod impl_bsd {
 
             if ret == 0 {
                 Ok(super::UCred {
-                    uid: uid.assume_init(),
-                    gid: gid.assume_init(),
+                    uid: uid.assume_init() as unix::uid_t,
+                    gid: gid.assume_init() as unix::gid_t,
                     pid: None,
                 })
             } else {
@@ -135,7 +186,7 @@ pub(crate) mod impl_bsd {
 
 #[cfg(any(target_os = "macos", target_os = "ios"))]
 pub(crate) mod impl_macos {
-    use crate::net::unix::UnixStream;
+    use crate::net::unix::{self, UnixStream};
 
     use libc::{c_void, getpeereid, getsockopt, pid_t, LOCAL_PEEREPID, SOL_LOCAL};
     use std::io;
@@ -169,9 +220,9 @@ pub(crate) mod impl_macos {
 
             if ret == 0 {
                 Ok(super::UCred {
-                    uid: uid.assume_init(),
-                    gid: gid.assume_init(),
-                    pid: Some(pid.assume_init()),
+                    uid: uid.assume_init() as unix::uid_t,
+                    gid: gid.assume_init() as unix::gid_t,
+                    pid: Some(pid.assume_init() as unix::pid_t),
                 })
             } else {
                 Err(io::Error::last_os_error())
@@ -182,7 +233,7 @@ pub(crate) mod impl_macos {
 
 #[cfg(any(target_os = "solaris", target_os = "illumos"))]
 pub(crate) mod impl_solaris {
-    use crate::net::unix::UnixStream;
+    use crate::net::unix::{self, UnixStream};
     use std::io;
     use std::os::unix::io::AsRawFd;
     use std::ptr;
@@ -202,9 +253,37 @@ pub(crate) mod impl_solaris {
                 libc::ucred_free(cred);
 
                 Ok(super::UCred {
-                    uid,
-                    gid,
-                    pid: Some(pid),
+                    uid: uid as unix::uid_t,
+                    gid: gid as unix::gid_t,
+                    pid: Some(pid as unix::pid_t),
+                })
+            } else {
+                Err(io::Error::last_os_error())
+            }
+        }
+    }
+}
+
+#[cfg(target_os = "aix")]
+pub(crate) mod impl_aix {
+    use crate::net::unix::UnixStream;
+    use std::io;
+    use std::os::unix::io::AsRawFd;
+
+    pub(crate) fn get_peer_cred(sock: &UnixStream) -> io::Result<super::UCred> {
+        unsafe {
+            let raw_fd = sock.as_raw_fd();
+
+            let mut uid = std::mem::MaybeUninit::uninit();
+            let mut gid = std::mem::MaybeUninit::uninit();
+
+            let ret = libc::getpeereid(raw_fd, uid.as_mut_ptr(), gid.as_mut_ptr());
+
+            if ret == 0 {
+                Ok(super::UCred {
+                    uid: uid.assume_init(),
+                    gid: gid.assume_init(),
+                    pid: None,
                 })
             } else {
                 Err(io::Error::last_os_error())