Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

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

6 files changed, 847 insertions, 0 deletions

diff --git a/third_party/rust/futures-io/.cargo-checksum.json b/third_party/rust/futures-io/.cargo-checksum.json
new file mode 100644
index 0000000000..7667f2a1ff
--- /dev/null
+++ b/third_party/rust/futures-io/.cargo-checksum.json
@@ -0,0 +1 @@
+{"files":{"Cargo.toml":"029c521e9beca1368117897b49b82a08400bc00780a891d03d88cc3af538343d","LICENSE-APACHE":"275c491d6d1160553c32fd6127061d7f9606c3ea25abfad6ca3f6ed088785427","LICENSE-MIT":"6652c868f35dfe5e8ef636810a4e576b9d663f3a17fb0f5613ad73583e1b88fd","README.md":"575430be5c47352d85f36b44dcc2c2851a6a19e2384593415c4af22c6654cee7","src/lib.rs":"526e9700c28250b7512f122952257d57adc38eb001af92ef25bdb48a8c453175"},"package":"bfb8371b6fb2aeb2d280374607aeabfc99d95c72edfe51692e42d3d7f0d08531"}
\ No newline at end of file
diff --git a/third_party/rust/futures-io/Cargo.toml b/third_party/rust/futures-io/Cargo.toml
new file mode 100644
index 0000000000..36a86a8345
--- /dev/null
+++ b/third_party/rust/futures-io/Cargo.toml
@@ -0,0 +1,37 @@
+# THIS FILE IS AUTOMATICALLY GENERATED BY CARGO
+#
+# When uploading crates to the registry Cargo will automatically
+# "normalize" Cargo.toml files for maximal compatibility
+# with all versions of Cargo and also rewrite `path` dependencies
+# to registry (e.g., crates.io) dependencies.
+#
+# If you are reading this file be aware that the original Cargo.toml
+# will likely look very different (and much more reasonable).
+# See Cargo.toml.orig for the original contents.
+
+[package]
+edition = "2018"
+rust-version = "1.36"
+name = "futures-io"
+version = "0.3.26"
+description = """
+The `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and `AsyncBufRead` traits for the futures-rs library.
+"""
+homepage = "https://rust-lang.github.io/futures-rs"
+readme = "README.md"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/futures-rs"
+
+[package.metadata.docs.rs]
+all-features = true
+rustdoc-args = [
+    "--cfg",
+    "docsrs",
+]
+
+[dependencies]
+
+[features]
+default = ["std"]
+std = []
+unstable = []
diff --git a/third_party/rust/futures-io/LICENSE-APACHE b/third_party/rust/futures-io/LICENSE-APACHE
new file mode 100644
index 0000000000..9eb0b097f5
--- /dev/null
+++ b/third_party/rust/futures-io/LICENSE-APACHE
@@ -0,0 +1,202 @@
+                              Apache License
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+5. Submission of Contributions. Unless You explicitly state otherwise,
+   any Contribution intentionally submitted for inclusion in the Work
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+6. Trademarks. This License does not grant permission to use the trade
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+9. Accepting Warranty or Additional Liability. While redistributing
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+END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+   To apply the Apache License to your work, attach the following
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+Copyright (c) 2016 Alex Crichton
+Copyright (c) 2017 The Tokio Authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
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+You may obtain a copy of the License at
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+	http://www.apache.org/licenses/LICENSE-2.0
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diff --git a/third_party/rust/futures-io/LICENSE-MIT b/third_party/rust/futures-io/LICENSE-MIT
new file mode 100644
index 0000000000..8ad082ec4f
--- /dev/null
+++ b/third_party/rust/futures-io/LICENSE-MIT
@@ -0,0 +1,26 @@
+Copyright (c) 2016 Alex Crichton
+Copyright (c) 2017 The Tokio Authors
+
+Permission is hereby granted, free of charge, to any
+person obtaining a copy of this software and associated
+documentation files (the "Software"), to deal in the
+Software without restriction, including without
+limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software
+is furnished to do so, subject to the following
+conditions:
+
+The above copyright notice and this permission notice
+shall be included in all copies or substantial portions
+of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
+ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
+TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
+SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
+IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
diff --git a/third_party/rust/futures-io/README.md b/third_party/rust/futures-io/README.md
new file mode 100644
index 0000000000..da6eec28ba
--- /dev/null
+++ b/third_party/rust/futures-io/README.md
@@ -0,0 +1,23 @@
+# futures-io
+
+The `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and `AsyncBufRead` traits for the futures-rs library.
+
+## Usage
+
+Add this to your `Cargo.toml`:
+
+```toml
+[dependencies]
+futures-io = "0.3"
+```
+
+The current `futures-io` requires Rust 1.36 or later.
+
+## License
+
+Licensed under either of [Apache License, Version 2.0](LICENSE-APACHE) or
+[MIT license](LICENSE-MIT) at your option.
+
+Unless you explicitly state otherwise, any contribution intentionally submitted
+for inclusion in the work by you, as defined in the Apache-2.0 license, shall
+be dual licensed as above, without any additional terms or conditions.
diff --git a/third_party/rust/futures-io/src/lib.rs b/third_party/rust/futures-io/src/lib.rs
new file mode 100644
index 0000000000..e91eb78492
--- /dev/null
+++ b/third_party/rust/futures-io/src/lib.rs
@@ -0,0 +1,558 @@
+//! Asynchronous I/O
+//!
+//! This crate contains the `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and
+//! `AsyncBufRead` traits, the asynchronous analogs to
+//! `std::io::{Read, Write, Seek, BufRead}`. The primary difference is
+//! that these traits integrate with the asynchronous task system.
+//!
+//! All items of this library are only available when the `std` feature of this
+//! library is activated, and it is activated by default.
+
+#![cfg_attr(not(feature = "std"), no_std)]
+#![warn(missing_debug_implementations, missing_docs, rust_2018_idioms, unreachable_pub)]
+// It cannot be included in the published code because this lints have false positives in the minimum required version.
+#![cfg_attr(test, warn(single_use_lifetimes))]
+#![doc(test(
+    no_crate_inject,
+    attr(
+        deny(warnings, rust_2018_idioms, single_use_lifetimes),
+        allow(dead_code, unused_assignments, unused_variables)
+    )
+))]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+
+#[cfg(feature = "std")]
+mod if_std {
+    use std::io;
+    use std::ops::DerefMut;
+    use std::pin::Pin;
+    use std::task::{Context, Poll};
+
+    // Re-export some types from `std::io` so that users don't have to deal
+    // with conflicts when `use`ing `futures::io` and `std::io`.
+    #[allow(unreachable_pub)] // https://github.com/rust-lang/rust/issues/57411
+    #[doc(no_inline)]
+    pub use io::{Error, ErrorKind, IoSlice, IoSliceMut, Result, SeekFrom};
+
+    /// Read bytes asynchronously.
+    ///
+    /// This trait is analogous to the `std::io::Read` trait, but integrates
+    /// with the asynchronous task system. In particular, the `poll_read`
+    /// method, unlike `Read::read`, will automatically queue the current task
+    /// for wakeup and return if data is not yet available, rather than blocking
+    /// the calling thread.
+    pub trait AsyncRead {
+        /// Attempt to read from the `AsyncRead` into `buf`.
+        ///
+        /// On success, returns `Poll::Ready(Ok(num_bytes_read))`.
+        ///
+        /// If no data is available for reading, the method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object becomes
+        /// readable or is closed.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_read(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            buf: &mut [u8],
+        ) -> Poll<Result<usize>>;
+
+        /// Attempt to read from the `AsyncRead` into `bufs` using vectored
+        /// IO operations.
+        ///
+        /// This method is similar to `poll_read`, but allows data to be read
+        /// into multiple buffers using a single operation.
+        ///
+        /// On success, returns `Poll::Ready(Ok(num_bytes_read))`.
+        ///
+        /// If no data is available for reading, the method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object becomes
+        /// readable or is closed.
+        /// By default, this method delegates to using `poll_read` on the first
+        /// nonempty buffer in `bufs`, or an empty one if none exists. Objects which
+        /// support vectored IO should override this method.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_read_vectored(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            bufs: &mut [IoSliceMut<'_>],
+        ) -> Poll<Result<usize>> {
+            for b in bufs {
+                if !b.is_empty() {
+                    return self.poll_read(cx, b);
+                }
+            }
+
+            self.poll_read(cx, &mut [])
+        }
+    }
+
+    /// Write bytes asynchronously.
+    ///
+    /// This trait is analogous to the `std::io::Write` trait, but integrates
+    /// with the asynchronous task system. In particular, the `poll_write`
+    /// method, unlike `Write::write`, will automatically queue the current task
+    /// for wakeup and return if the writer cannot take more data, rather than blocking
+    /// the calling thread.
+    pub trait AsyncWrite {
+        /// Attempt to write bytes from `buf` into the object.
+        ///
+        /// On success, returns `Poll::Ready(Ok(num_bytes_written))`.
+        ///
+        /// If the object is not ready for writing, the method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object becomes
+        /// writable or is closed.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        ///
+        /// `poll_write` must try to make progress by flushing the underlying object if
+        /// that is the only way the underlying object can become writable again.
+        fn poll_write(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            buf: &[u8],
+        ) -> Poll<Result<usize>>;
+
+        /// Attempt to write bytes from `bufs` into the object using vectored
+        /// IO operations.
+        ///
+        /// This method is similar to `poll_write`, but allows data from multiple buffers to be written
+        /// using a single operation.
+        ///
+        /// On success, returns `Poll::Ready(Ok(num_bytes_written))`.
+        ///
+        /// If the object is not ready for writing, the method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object becomes
+        /// writable or is closed.
+        ///
+        /// By default, this method delegates to using `poll_write` on the first
+        /// nonempty buffer in `bufs`, or an empty one if none exists. Objects which
+        /// support vectored IO should override this method.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_write_vectored(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            bufs: &[IoSlice<'_>],
+        ) -> Poll<Result<usize>> {
+            for b in bufs {
+                if !b.is_empty() {
+                    return self.poll_write(cx, b);
+                }
+            }
+
+            self.poll_write(cx, &[])
+        }
+
+        /// Attempt to flush the object, ensuring that any buffered data reach
+        /// their destination.
+        ///
+        /// On success, returns `Poll::Ready(Ok(()))`.
+        ///
+        /// If flushing cannot immediately complete, this method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object can make
+        /// progress towards flushing.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        ///
+        /// It only makes sense to do anything here if you actually buffer data.
+        fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>;
+
+        /// Attempt to close the object.
+        ///
+        /// On success, returns `Poll::Ready(Ok(()))`.
+        ///
+        /// If closing cannot immediately complete, this function returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object can make
+        /// progress towards closing.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>>;
+    }
+
+    /// Seek bytes asynchronously.
+    ///
+    /// This trait is analogous to the `std::io::Seek` trait, but integrates
+    /// with the asynchronous task system. In particular, the `poll_seek`
+    /// method, unlike `Seek::seek`, will automatically queue the current task
+    /// for wakeup and return if data is not yet available, rather than blocking
+    /// the calling thread.
+    pub trait AsyncSeek {
+        /// Attempt to seek to an offset, in bytes, in a stream.
+        ///
+        /// A seek beyond the end of a stream is allowed, but behavior is defined
+        /// by the implementation.
+        ///
+        /// If the seek operation completed successfully,
+        /// this method returns the new position from the start of the stream.
+        /// That position can be used later with [`SeekFrom::Start`].
+        ///
+        /// # Errors
+        ///
+        /// Seeking to a negative offset is considered an error.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_seek(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            pos: SeekFrom,
+        ) -> Poll<Result<u64>>;
+    }
+
+    /// Read bytes asynchronously.
+    ///
+    /// This trait is analogous to the `std::io::BufRead` trait, but integrates
+    /// with the asynchronous task system. In particular, the `poll_fill_buf`
+    /// method, unlike `BufRead::fill_buf`, will automatically queue the current task
+    /// for wakeup and return if data is not yet available, rather than blocking
+    /// the calling thread.
+    pub trait AsyncBufRead: AsyncRead {
+        /// Attempt to return the contents of the internal buffer, filling it with more data
+        /// from the inner reader if it is empty.
+        ///
+        /// On success, returns `Poll::Ready(Ok(buf))`.
+        ///
+        /// If no data is available for reading, the method returns
+        /// `Poll::Pending` and arranges for the current task (via
+        /// `cx.waker().wake_by_ref()`) to receive a notification when the object becomes
+        /// readable or is closed.
+        ///
+        /// This function is a lower-level call. It needs to be paired with the
+        /// [`consume`] method to function properly. When calling this
+        /// method, none of the contents will be "read" in the sense that later
+        /// calling [`poll_read`] may return the same contents. As such, [`consume`] must
+        /// be called with the number of bytes that are consumed from this buffer to
+        /// ensure that the bytes are never returned twice.
+        ///
+        /// [`poll_read`]: AsyncRead::poll_read
+        /// [`consume`]: AsyncBufRead::consume
+        ///
+        /// An empty buffer returned indicates that the stream has reached EOF.
+        ///
+        /// # Implementation
+        ///
+        /// This function may not return errors of kind `WouldBlock` or
+        /// `Interrupted`.  Implementations must convert `WouldBlock` into
+        /// `Poll::Pending` and either internally retry or convert
+        /// `Interrupted` into another error kind.
+        fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<&[u8]>>;
+
+        /// Tells this buffer that `amt` bytes have been consumed from the buffer,
+        /// so they should no longer be returned in calls to [`poll_read`].
+        ///
+        /// This function is a lower-level call. It needs to be paired with the
+        /// [`poll_fill_buf`] method to function properly. This function does
+        /// not perform any I/O, it simply informs this object that some amount of
+        /// its buffer, returned from [`poll_fill_buf`], has been consumed and should
+        /// no longer be returned. As such, this function may do odd things if
+        /// [`poll_fill_buf`] isn't called before calling it.
+        ///
+        /// The `amt` must be `<=` the number of bytes in the buffer returned by
+        /// [`poll_fill_buf`].
+        ///
+        /// [`poll_read`]: AsyncRead::poll_read
+        /// [`poll_fill_buf`]: AsyncBufRead::poll_fill_buf
+        fn consume(self: Pin<&mut Self>, amt: usize);
+    }
+
+    macro_rules! deref_async_read {
+        () => {
+            fn poll_read(
+                mut self: Pin<&mut Self>,
+                cx: &mut Context<'_>,
+                buf: &mut [u8],
+            ) -> Poll<Result<usize>> {
+                Pin::new(&mut **self).poll_read(cx, buf)
+            }
+
+            fn poll_read_vectored(
+                mut self: Pin<&mut Self>,
+                cx: &mut Context<'_>,
+                bufs: &mut [IoSliceMut<'_>],
+            ) -> Poll<Result<usize>> {
+                Pin::new(&mut **self).poll_read_vectored(cx, bufs)
+            }
+        };
+    }
+
+    impl<T: ?Sized + AsyncRead + Unpin> AsyncRead for Box<T> {
+        deref_async_read!();
+    }
+
+    impl<T: ?Sized + AsyncRead + Unpin> AsyncRead for &mut T {
+        deref_async_read!();
+    }
+
+    impl<P> AsyncRead for Pin<P>
+    where
+        P: DerefMut + Unpin,
+        P::Target: AsyncRead,
+    {
+        fn poll_read(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            buf: &mut [u8],
+        ) -> Poll<Result<usize>> {
+            self.get_mut().as_mut().poll_read(cx, buf)
+        }
+
+        fn poll_read_vectored(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            bufs: &mut [IoSliceMut<'_>],
+        ) -> Poll<Result<usize>> {
+            self.get_mut().as_mut().poll_read_vectored(cx, bufs)
+        }
+    }
+
+    macro_rules! delegate_async_read_to_stdio {
+        () => {
+            fn poll_read(
+                mut self: Pin<&mut Self>,
+                _: &mut Context<'_>,
+                buf: &mut [u8],
+            ) -> Poll<Result<usize>> {
+                Poll::Ready(io::Read::read(&mut *self, buf))
+            }
+
+            fn poll_read_vectored(
+                mut self: Pin<&mut Self>,
+                _: &mut Context<'_>,
+                bufs: &mut [IoSliceMut<'_>],
+            ) -> Poll<Result<usize>> {
+                Poll::Ready(io::Read::read_vectored(&mut *self, bufs))
+            }
+        };
+    }
+
+    impl AsyncRead for &[u8] {
+        delegate_async_read_to_stdio!();
+    }
+
+    macro_rules! deref_async_write {
+        () => {
+            fn poll_write(
+                mut self: Pin<&mut Self>,
+                cx: &mut Context<'_>,
+                buf: &[u8],
+            ) -> Poll<Result<usize>> {
+                Pin::new(&mut **self).poll_write(cx, buf)
+            }
+
+            fn poll_write_vectored(
+                mut self: Pin<&mut Self>,
+                cx: &mut Context<'_>,
+                bufs: &[IoSlice<'_>],
+            ) -> Poll<Result<usize>> {
+                Pin::new(&mut **self).poll_write_vectored(cx, bufs)
+            }
+
+            fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+                Pin::new(&mut **self).poll_flush(cx)
+            }
+
+            fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+                Pin::new(&mut **self).poll_close(cx)
+            }
+        };
+    }
+
+    impl<T: ?Sized + AsyncWrite + Unpin> AsyncWrite for Box<T> {
+        deref_async_write!();
+    }
+
+    impl<T: ?Sized + AsyncWrite + Unpin> AsyncWrite for &mut T {
+        deref_async_write!();
+    }
+
+    impl<P> AsyncWrite for Pin<P>
+    where
+        P: DerefMut + Unpin,
+        P::Target: AsyncWrite,
+    {
+        fn poll_write(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            buf: &[u8],
+        ) -> Poll<Result<usize>> {
+            self.get_mut().as_mut().poll_write(cx, buf)
+        }
+
+        fn poll_write_vectored(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            bufs: &[IoSlice<'_>],
+        ) -> Poll<Result<usize>> {
+            self.get_mut().as_mut().poll_write_vectored(cx, bufs)
+        }
+
+        fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+            self.get_mut().as_mut().poll_flush(cx)
+        }
+
+        fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+            self.get_mut().as_mut().poll_close(cx)
+        }
+    }
+
+    macro_rules! delegate_async_write_to_stdio {
+        () => {
+            fn poll_write(
+                mut self: Pin<&mut Self>,
+                _: &mut Context<'_>,
+                buf: &[u8],
+            ) -> Poll<Result<usize>> {
+                Poll::Ready(io::Write::write(&mut *self, buf))
+            }
+
+            fn poll_write_vectored(
+                mut self: Pin<&mut Self>,
+                _: &mut Context<'_>,
+                bufs: &[IoSlice<'_>],
+            ) -> Poll<Result<usize>> {
+                Poll::Ready(io::Write::write_vectored(&mut *self, bufs))
+            }
+
+            fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<()>> {
+                Poll::Ready(io::Write::flush(&mut *self))
+            }
+
+            fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
+                self.poll_flush(cx)
+            }
+        };
+    }
+
+    impl AsyncWrite for Vec<u8> {
+        delegate_async_write_to_stdio!();
+    }
+
+    macro_rules! deref_async_seek {
+        () => {
+            fn poll_seek(
+                mut self: Pin<&mut Self>,
+                cx: &mut Context<'_>,
+                pos: SeekFrom,
+            ) -> Poll<Result<u64>> {
+                Pin::new(&mut **self).poll_seek(cx, pos)
+            }
+        };
+    }
+
+    impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for Box<T> {
+        deref_async_seek!();
+    }
+
+    impl<T: ?Sized + AsyncSeek + Unpin> AsyncSeek for &mut T {
+        deref_async_seek!();
+    }
+
+    impl<P> AsyncSeek for Pin<P>
+    where
+        P: DerefMut + Unpin,
+        P::Target: AsyncSeek,
+    {
+        fn poll_seek(
+            self: Pin<&mut Self>,
+            cx: &mut Context<'_>,
+            pos: SeekFrom,
+        ) -> Poll<Result<u64>> {
+            self.get_mut().as_mut().poll_seek(cx, pos)
+        }
+    }
+
+    macro_rules! deref_async_buf_read {
+        () => {
+            fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<&[u8]>> {
+                Pin::new(&mut **self.get_mut()).poll_fill_buf(cx)
+            }
+
+            fn consume(mut self: Pin<&mut Self>, amt: usize) {
+                Pin::new(&mut **self).consume(amt)
+            }
+        };
+    }
+
+    impl<T: ?Sized + AsyncBufRead + Unpin> AsyncBufRead for Box<T> {
+        deref_async_buf_read!();
+    }
+
+    impl<T: ?Sized + AsyncBufRead + Unpin> AsyncBufRead for &mut T {
+        deref_async_buf_read!();
+    }
+
+    impl<P> AsyncBufRead for Pin<P>
+    where
+        P: DerefMut + Unpin,
+        P::Target: AsyncBufRead,
+    {
+        fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<&[u8]>> {
+            self.get_mut().as_mut().poll_fill_buf(cx)
+        }
+
+        fn consume(self: Pin<&mut Self>, amt: usize) {
+            self.get_mut().as_mut().consume(amt)
+        }
+    }
+
+    macro_rules! delegate_async_buf_read_to_stdio {
+        () => {
+            fn poll_fill_buf(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<&[u8]>> {
+                Poll::Ready(io::BufRead::fill_buf(self.get_mut()))
+            }
+
+            fn consume(self: Pin<&mut Self>, amt: usize) {
+                io::BufRead::consume(self.get_mut(), amt)
+            }
+        };
+    }
+
+    impl AsyncBufRead for &[u8] {
+        delegate_async_buf_read_to_stdio!();
+    }
+}
+
+#[cfg(feature = "std")]
+pub use self::if_std::*;