1 files changed, 47 insertions, 0 deletions
diff --git a/third_party/rust/tokio/src/io/util/shutdown.rs b/third_party/rust/tokio/src/io/util/shutdown.rs
new file mode 100644
index 0000000000..f24e288541
--- /dev/null
+++ b/third_party/rust/tokio/src/io/util/shutdown.rs
@@ -0,0 +1,47 @@
+use crate::io::AsyncWrite;
+
+use std::future::Future;
+use std::io;
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+cfg_io_util! {
+    /// A future used to shutdown an I/O object.
+    ///
+    /// Created by the [`AsyncWriteExt::shutdown`] function.
+    #[derive(Debug)]
+    pub struct Shutdown<'a, A: ?Sized> {
+        a: &'a mut A,
+    }
+}
+
+/// Creates a future which will shutdown an I/O object.
+pub(super) fn shutdown<A>(a: &mut A) -> Shutdown<'_, A>
+where
+    A: AsyncWrite + Unpin + ?Sized,
+{
+    Shutdown { a }
+}
+
+impl<A> Future for Shutdown<'_, A>
+where
+    A: AsyncWrite + Unpin + ?Sized,
+{
+    type Output = io::Result<()>;
+
+    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        let me = &mut *self;
+        Pin::new(&mut *me.a).poll_shutdown(cx)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn assert_unpin() {
+        use std::marker::PhantomPinned;
+        crate::is_unpin::<Shutdown<'_, PhantomPinned>>();
+    }
+}