Import 'futures-io' rust crate version 0.3.4
Bug: b/151760391
Test: m crosvm.experimental
Change-Id: If58ad3e89b259c126905fe76a34111230cb0fe24
diff --git a/Android.bp b/Android.bp
new file mode 100644
index 0000000..7e8ccdd
--- /dev/null
+++ b/Android.bp
@@ -0,0 +1,12 @@
+// This file is generated by cargo2android.py.
+
+rust_library_host_rlib {
+ name: "libfutures_io",
+ crate_name: "futures_io",
+ srcs: ["src/lib.rs"],
+ edition: "2018",
+ features: [
+ "default",
+ "std",
+ ],
+}
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..5aee74c
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,32 @@
+# 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 believe there's an error in this file please file an
+# issue against the rust-lang/cargo repository. If you're
+# editing this file be aware that the upstream Cargo.toml
+# will likely look very different (and much more reasonable)
+
+[package]
+edition = "2018"
+name = "futures-io"
+version = "0.3.4"
+authors = ["Alex Crichton <alex@alexcrichton.com>"]
+description = "The `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and `AsyncBufRead` traits for the futures-rs library.\n"
+homepage = "https://rust-lang.github.io/futures-rs"
+documentation = "https://docs.rs/futures-io/0.3.0"
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/futures-rs"
+[package.metadata.docs.rs]
+all-features = true
+
+[dependencies]
+
+[features]
+default = ["std"]
+read-initializer = []
+std = []
+unstable = []
diff --git a/Cargo.toml.orig b/Cargo.toml.orig
new file mode 100644
index 0000000..76f2565
--- /dev/null
+++ b/Cargo.toml.orig
@@ -0,0 +1,27 @@
+[package]
+name = "futures-io"
+edition = "2018"
+version = "0.3.4"
+authors = ["Alex Crichton <alex@alexcrichton.com>"]
+license = "MIT OR Apache-2.0"
+repository = "https://github.com/rust-lang/futures-rs"
+homepage = "https://rust-lang.github.io/futures-rs"
+documentation = "https://docs.rs/futures-io/0.3.0"
+description = """
+The `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and `AsyncBufRead` traits for the futures-rs library.
+"""
+
+[features]
+default = ["std"]
+std = []
+
+# Unstable features
+# These features are outside of the normal semver guarantees and require the
+# `unstable` feature as an explicit opt-in to unstable API.
+unstable = []
+read-initializer = []
+
+[dependencies]
+
+[package.metadata.docs.rs]
+all-features = true
diff --git a/LICENSE b/LICENSE
new file mode 120000
index 0000000..6b579aa
--- /dev/null
+++ b/LICENSE
@@ -0,0 +1 @@
+LICENSE-APACHE
\ No newline at end of file
diff --git a/LICENSE-APACHE b/LICENSE-APACHE
new file mode 100644
index 0000000..9eb0b09
--- /dev/null
+++ b/LICENSE-APACHE
@@ -0,0 +1,202 @@
+ Apache License
+ Version 2.0, January 2004
+ http://www.apache.org/licenses/
+
+TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+1. Definitions.
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+5. Submission of Contributions. Unless You explicitly state otherwise,
+ any Contribution intentionally submitted for inclusion in the Work
+ by You to the Licensor shall be under the terms and conditions of
+ this License, without any additional terms or conditions.
+ Notwithstanding the above, nothing herein shall supersede or modify
+ the terms of any separate license agreement you may have executed
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+6. Trademarks. This License does not grant permission to use the trade
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+7. Disclaimer of Warranty. Unless required by applicable law or
+ agreed to in writing, Licensor provides the Work (and each
+ Contributor provides its Contributions) on an "AS IS" BASIS,
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+
+8. Limitation of Liability. In no event and under no legal theory,
+ whether in tort (including negligence), contract, or otherwise,
+ unless required by applicable law (such as deliberate and grossly
+ negligent acts) or agreed to in writing, shall any Contributor be
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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
+ boilerplate notice, with the fields enclosed by brackets "[]"
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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");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
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diff --git a/LICENSE-MIT b/LICENSE-MIT
new file mode 100644
index 0000000..8ad082e
--- /dev/null
+++ b/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/METADATA b/METADATA
new file mode 100644
index 0000000..99ccebd
--- /dev/null
+++ b/METADATA
@@ -0,0 +1,18 @@
+name: "futures-io"
+description:
+ "The `AsyncRead`, `AsyncWrite`, `AsyncSeek`, and `AsyncBufRead` traits for "
+ "the futures-rs library."
+
+third_party {
+ url {
+ type: HOMEPAGE
+ value: "https://crates.io/crates/futures-io"
+ }
+ url {
+ type: GIT
+ value: "https://github.com/rust-lang/futures-rs"
+ }
+ version: "0.3.4"
+ last_upgrade_date { year: 2020 month: 3 day: 17 }
+ license_type: NOTICE
+}
diff --git a/MODULE_LICENSE_APACHE2 b/MODULE_LICENSE_APACHE2
new file mode 100644
index 0000000..e69de29
--- /dev/null
+++ b/MODULE_LICENSE_APACHE2
diff --git a/NOTICE b/NOTICE
new file mode 120000
index 0000000..7a694c9
--- /dev/null
+++ b/NOTICE
@@ -0,0 +1 @@
+LICENSE
\ No newline at end of file
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..34fb241
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,567 @@
+//! 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(all(feature = "read-initializer", feature = "std"), feature(read_initializer))]
+
+#![cfg_attr(not(feature = "std"), no_std)]
+
+#![warn(missing_docs, missing_debug_implementations, 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))]
+#![warn(clippy::all)]
+
+#![doc(test(attr(deny(warnings), allow(dead_code, unused_assignments, unused_variables))))]
+
+#![doc(html_root_url = "https://docs.rs/futures-io/0.3.0")]
+
+#[cfg(all(feature = "read-initializer", not(feature = "unstable")))]
+compile_error!("The `read-initializer` feature requires the `unstable` feature as an explicit opt-in to unstable features");
+
+#[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
+ pub use io::{
+ Error as Error,
+ ErrorKind as ErrorKind,
+ Result as Result,
+ IoSlice as IoSlice,
+ IoSliceMut as IoSliceMut,
+ SeekFrom as SeekFrom,
+ };
+
+ #[cfg(feature = "read-initializer")]
+ #[allow(unreachable_pub)] // https://github.com/rust-lang/rust/issues/57411
+ pub use io::Initializer as Initializer;
+
+ /// 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 {
+ /// Determines if this `AsyncRead`er can work with buffers of
+ /// uninitialized memory.
+ ///
+ /// The default implementation returns an initializer which will zero
+ /// buffers.
+ ///
+ /// This method is only available when the `read-initializer` feature of this
+ /// library is activated.
+ ///
+ /// # Safety
+ ///
+ /// This method is `unsafe` because an `AsyncRead`er could otherwise
+ /// return a non-zeroing `Initializer` from another `AsyncRead` type
+ /// without an `unsafe` block.
+ #[cfg(feature = "read-initializer")]
+ #[inline]
+ unsafe fn initializer(&self) -> Initializer {
+ Initializer::zeroing()
+ }
+
+ /// 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 data is not yet available, 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.
+ 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.
+ 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 {
+ () => {
+ #[cfg(feature = "read-initializer")]
+ unsafe fn initializer(&self) -> Initializer {
+ (**self).initializer()
+ }
+
+ 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,
+ {
+ #[cfg(feature = "read-initializer")]
+ unsafe fn initializer(&self) -> Initializer {
+ (**self).initializer()
+ }
+
+ 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 {
+ () => {
+ #[cfg(feature = "read-initializer")]
+ unsafe fn initializer(&self) -> Initializer {
+ io::Read::initializer(self)
+ }
+
+ 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::*;
