| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/git/checkouts/tokio-377c595163f99a10/dfe252d/tokio/src/io/async_write.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>async_write.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../normalize.css"><link rel="stylesheet" href="../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../ayu.css" disabled><link rel="stylesheet" href="../../../dark.css" disabled><link rel="stylesheet" href="../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../storage.js"></script><script defer src="../../../source-script.js"></script><script defer src="../../../source-files.js"></script><script defer src="../../../main.js"></script><noscript><link rel="stylesheet" href="../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../tokio/index.html"><div class="logo-container"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../tokio/index.html"><img class="rust-logo" src="../../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span>std::io::{<span class="self">self</span>, IoSlice}; |
| <span class="kw">use </span>std::ops::DerefMut; |
| <span class="kw">use </span>std::pin::Pin; |
| <span class="kw">use </span>std::task::{Context, Poll}; |
| |
| <span class="doccomment">/// Writes bytes asynchronously. |
| /// |
| /// The trait inherits from [`std::io::Write`] and indicates that an I/O object is |
| /// **nonblocking**. All non-blocking I/O objects must return an error when |
| /// bytes cannot be written instead of blocking the current thread. |
| /// |
| /// Specifically, this means that the [`poll_write`] function will return one of |
| /// the following: |
| /// |
| /// * `Poll::Ready(Ok(n))` means that `n` bytes of data was immediately |
| /// written. |
| /// |
| /// * `Poll::Pending` means that no data was written from the buffer |
| /// provided. The I/O object is not currently writable but may become writable |
| /// in the future. Most importantly, **the current future's task is scheduled |
| /// to get unparked when the object is writable**. This means that like |
| /// `Future::poll` you'll receive a notification when the I/O object is |
| /// writable again. |
| /// |
| /// * `Poll::Ready(Err(e))` for other errors are standard I/O errors coming from the |
| /// underlying object. |
| /// |
| /// This trait importantly means that the [`write`][stdwrite] method only works in |
| /// the context of a future's task. The object may panic if used outside of a task. |
| /// |
| /// Note that this trait also represents that the [`Write::flush`][stdflush] method |
| /// works very similarly to the `write` method, notably that `Ok(())` means that the |
| /// writer has successfully been flushed, a "would block" error means that the |
| /// current task is ready to receive a notification when flushing can make more |
| /// progress, and otherwise normal errors can happen as well. |
| /// |
| /// Utilities for working with `AsyncWrite` values are provided by |
| /// [`AsyncWriteExt`]. |
| /// |
| /// [`std::io::Write`]: std::io::Write |
| /// [`poll_write`]: AsyncWrite::poll_write() |
| /// [stdwrite]: std::io::Write::write() |
| /// [stdflush]: std::io::Write::flush() |
| /// [`AsyncWriteExt`]: crate::io::AsyncWriteExt |
| </span><span class="kw">pub trait </span>AsyncWrite { |
| <span class="doccomment">/// Attempt to write bytes from `buf` into the object. |
| /// |
| /// On success, returns `Poll::Ready(Ok(num_bytes_written))`. If successful, |
| /// then it must be guaranteed that `n <= buf.len()`. A return value of `0` |
| /// typically means that the underlying object is no longer able to accept |
| /// bytes and will likely not be able to in the future as well, or that the |
| /// buffer provided is empty. |
| /// |
| /// If the object is not ready for writing, the method returns |
| /// `Poll::Pending` and arranges for the current task (via |
| /// `cx.waker()`) to receive a notification when the object becomes |
| /// writable or is closed. |
| </span><span class="kw">fn </span>poll_write( |
| <span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<<span class="prelude-ty">Result</span><usize, io::Error>>; |
| |
| <span class="doccomment">/// Attempts 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()`) to receive a notification when the object can make |
| /// progress towards flushing. |
| </span><span class="kw">fn </span>poll_flush(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<<span class="prelude-ty">Result</span><(), io::Error>>; |
| |
| <span class="doccomment">/// Initiates or attempts to shut down this writer, returning success when |
| /// the I/O connection has completely shut down. |
| /// |
| /// This method is intended to be used for asynchronous shutdown of I/O |
| /// connections. For example this is suitable for implementing shutdown of a |
| /// TLS connection or calling `TcpStream::shutdown` on a proxied connection. |
| /// Protocols sometimes need to flush out final pieces of data or otherwise |
| /// perform a graceful shutdown handshake, reading/writing more data as |
| /// appropriate. This method is the hook for such protocols to implement the |
| /// graceful shutdown logic. |
| /// |
| /// This `shutdown` method is required by implementers of the |
| /// `AsyncWrite` trait. Wrappers typically just want to proxy this call |
| /// through to the wrapped type, and base types will typically implement |
| /// shutdown logic here or just return `Ok(().into())`. Note that if you're |
| /// wrapping an underlying `AsyncWrite` a call to `shutdown` implies that |
| /// transitively the entire stream has been shut down. After your wrapper's |
| /// shutdown logic has been executed you should shut down the underlying |
| /// stream. |
| /// |
| /// Invocation of a `shutdown` implies an invocation of `flush`. Once this |
| /// method returns `Ready` it implies that a flush successfully happened |
| /// before the shutdown happened. That is, callers don't need to call |
| /// `flush` before calling `shutdown`. They can rely that by calling |
| /// `shutdown` any pending buffered data will be written out. |
| /// |
| /// # Return value |
| /// |
| /// This function returns a `Poll<io::Result<()>>` classified as such: |
| /// |
| /// * `Poll::Ready(Ok(()))` - indicates that the connection was |
| /// successfully shut down and is now safe to deallocate/drop/close |
| /// resources associated with it. This method means that the current task |
| /// will no longer receive any notifications due to this method and the |
| /// I/O object itself is likely no longer usable. |
| /// |
| /// * `Poll::Pending` - indicates that shutdown is initiated but could |
| /// not complete just yet. This may mean that more I/O needs to happen to |
| /// continue this shutdown operation. The current task is scheduled to |
| /// receive a notification when it's otherwise ready to continue the |
| /// shutdown operation. When woken up this method should be called again. |
| /// |
| /// * `Poll::Ready(Err(e))` - indicates a fatal error has happened with shutdown, |
| /// indicating that the shutdown operation did not complete successfully. |
| /// This typically means that the I/O object is no longer usable. |
| /// |
| /// # Errors |
| /// |
| /// This function can return normal I/O errors through `Err`, described |
| /// above. Additionally this method may also render the underlying |
| /// `Write::write` method no longer usable (e.g. will return errors in the |
| /// future). It's recommended that once `shutdown` is called the |
| /// `write` method is no longer called. |
| /// |
| /// # Panics |
| /// |
| /// This function will panic if not called within the context of a future's |
| /// task. |
| </span><span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<<span class="prelude-ty">Result</span><(), io::Error>>; |
| |
| <span class="doccomment">/// Like [`poll_write`], except that it writes from a slice of buffers. |
| /// |
| /// Data is copied from each buffer in order, with the final buffer |
| /// read from possibly being only partially consumed. This method must |
| /// behave as a call to [`write`] with the buffers concatenated would. |
| /// |
| /// The default implementation calls [`poll_write`] with either the first nonempty |
| /// buffer provided, or an empty one if none exists. |
| /// |
| /// 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()`) to receive a notification when the object becomes |
| /// writable or is closed. |
| /// |
| /// # Note |
| /// |
| /// This should be implemented as a single "atomic" write action. If any |
| /// data has been partially written, it is wrong to return an error or |
| /// pending. |
| /// |
| /// [`poll_write`]: AsyncWrite::poll_write |
| </span><span class="kw">fn </span>poll_write_vectored( |
| <span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<<span class="prelude-ty">Result</span><usize, io::Error>> { |
| <span class="kw">let </span>buf = bufs |
| .iter() |
| .find(|b| !b.is_empty()) |
| .map_or(<span class="kw-2">&</span>[][..], |b| <span class="kw-2">&**</span>b); |
| <span class="self">self</span>.poll_write(cx, buf) |
| } |
| |
| <span class="doccomment">/// Determines if this writer has an efficient [`poll_write_vectored`] |
| /// implementation. |
| /// |
| /// If a writer does not override the default [`poll_write_vectored`] |
| /// implementation, code using it may want to avoid the method all together |
| /// and coalesce writes into a single buffer for higher performance. |
| /// |
| /// The default implementation returns `false`. |
| /// |
| /// [`poll_write_vectored`]: AsyncWrite::poll_write_vectored |
| </span><span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">false |
| </span>} |
| } |
| |
| <span class="macro">macro_rules! </span>deref_async_write { |
| () => { |
| <span class="kw">fn </span>poll_write( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| Pin::new(<span class="kw-2">&mut **</span><span class="self">self</span>).poll_write(cx, buf) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Pin::new(<span class="kw-2">&mut **</span><span class="self">self</span>).poll_write_vectored(cx, bufs) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| (<span class="kw-2">**</span><span class="self">self</span>).is_write_vectored() |
| } |
| |
| <span class="kw">fn </span>poll_flush(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Pin::new(<span class="kw-2">&mut **</span><span class="self">self</span>).poll_flush(cx) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Pin::new(<span class="kw-2">&mut **</span><span class="self">self</span>).poll_shutdown(cx) |
| } |
| }; |
| } |
| |
| <span class="kw">impl</span><T: <span class="question-mark">?</span>Sized + AsyncWrite + Unpin> AsyncWrite <span class="kw">for </span>Box<T> { |
| <span class="macro">deref_async_write!</span>(); |
| } |
| |
| <span class="kw">impl</span><T: <span class="question-mark">?</span>Sized + AsyncWrite + Unpin> AsyncWrite <span class="kw">for </span><span class="kw-2">&mut </span>T { |
| <span class="macro">deref_async_write!</span>(); |
| } |
| |
| <span class="kw">impl</span><P> AsyncWrite <span class="kw">for </span>Pin<P> |
| <span class="kw">where |
| </span>P: DerefMut + Unpin, |
| P::Target: AsyncWrite, |
| { |
| <span class="kw">fn </span>poll_write( |
| <span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| <span class="self">self</span>.get_mut().as_mut().poll_write(cx, buf) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| <span class="self">self</span>.get_mut().as_mut().poll_write_vectored(cx, bufs) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| (<span class="kw-2">**</span><span class="self">self</span>).is_write_vectored() |
| } |
| |
| <span class="kw">fn </span>poll_flush(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.get_mut().as_mut().poll_flush(cx) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.get_mut().as_mut().poll_shutdown(cx) |
| } |
| } |
| |
| <span class="kw">impl </span>AsyncWrite <span class="kw">for </span>Vec<u8> { |
| <span class="kw">fn </span>poll_write( |
| <span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| _cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| <span class="self">self</span>.get_mut().extend_from_slice(buf); |
| Poll::Ready(<span class="prelude-val">Ok</span>(buf.len())) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write_vectored(<span class="kw-2">&mut *</span><span class="self">self</span>, bufs)) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>poll_flush(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, _cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(<span class="prelude-val">Ok</span>(())) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, _cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(<span class="prelude-val">Ok</span>(())) |
| } |
| } |
| |
| <span class="kw">impl </span>AsyncWrite <span class="kw">for </span>io::Cursor<<span class="kw-2">&mut </span>[u8]> { |
| <span class="kw">fn </span>poll_write( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write(<span class="kw-2">&mut *</span><span class="self">self</span>, buf)) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write_vectored(<span class="kw-2">&mut *</span><span class="self">self</span>, bufs)) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>poll_flush(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(io::Write::flush(<span class="kw-2">&mut *</span><span class="self">self</span>)) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.poll_flush(cx) |
| } |
| } |
| |
| <span class="kw">impl </span>AsyncWrite <span class="kw">for </span>io::Cursor<<span class="kw-2">&mut </span>Vec<u8>> { |
| <span class="kw">fn </span>poll_write( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write(<span class="kw-2">&mut *</span><span class="self">self</span>, buf)) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write_vectored(<span class="kw-2">&mut *</span><span class="self">self</span>, bufs)) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>poll_flush(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(io::Write::flush(<span class="kw-2">&mut *</span><span class="self">self</span>)) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.poll_flush(cx) |
| } |
| } |
| |
| <span class="kw">impl </span>AsyncWrite <span class="kw">for </span>io::Cursor<Vec<u8>> { |
| <span class="kw">fn </span>poll_write( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write(<span class="kw-2">&mut *</span><span class="self">self</span>, buf)) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write_vectored(<span class="kw-2">&mut *</span><span class="self">self</span>, bufs)) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>poll_flush(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(io::Write::flush(<span class="kw-2">&mut *</span><span class="self">self</span>)) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.poll_flush(cx) |
| } |
| } |
| |
| <span class="kw">impl </span>AsyncWrite <span class="kw">for </span>io::Cursor<Box<[u8]>> { |
| <span class="kw">fn </span>poll_write( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| buf: <span class="kw-2">&</span>[u8], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write(<span class="kw-2">&mut *</span><span class="self">self</span>, buf)) |
| } |
| |
| <span class="kw">fn </span>poll_write_vectored( |
| <span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, |
| <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>, |
| bufs: <span class="kw-2">&</span>[IoSlice<<span class="lifetime">'_</span>>], |
| ) -> Poll<io::Result<usize>> { |
| Poll::Ready(io::Write::write_vectored(<span class="kw-2">&mut *</span><span class="self">self</span>, bufs)) |
| } |
| |
| <span class="kw">fn </span>is_write_vectored(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="bool-val">true |
| </span>} |
| |
| <span class="kw">fn </span>poll_flush(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, <span class="kw">_</span>: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| Poll::Ready(io::Write::flush(<span class="kw-2">&mut *</span><span class="self">self</span>)) |
| } |
| |
| <span class="kw">fn </span>poll_shutdown(<span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<io::Result<()>> { |
| <span class="self">self</span>.poll_flush(cx) |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="tokio" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |