tokio_util/io/
copy_to_bytes.rs

1use bytes::Bytes;
2use futures_core::stream::Stream;
3use futures_sink::Sink;
4use pin_project_lite::pin_project;
5use std::pin::Pin;
6use std::task::{Context, Poll};
7
8pin_project! {
9    /// A helper that wraps a [`Sink`]`<`[`Bytes`]`>` and converts it into a
10    /// [`Sink`]`<&'a [u8]>` by copying each byte slice into an owned [`Bytes`].
11    ///
12    /// See the documentation for [`SinkWriter`] for an example.
13    ///
14    /// [`Bytes`]: bytes::Bytes
15    /// [`SinkWriter`]: crate::io::SinkWriter
16    /// [`Sink`]: futures_sink::Sink
17    #[derive(Debug)]
18    pub struct CopyToBytes<S> {
19        #[pin]
20        inner: S,
21    }
22}
23
24impl<S> CopyToBytes<S> {
25    /// Creates a new [`CopyToBytes`].
26    pub fn new(inner: S) -> Self {
27        Self { inner }
28    }
29
30    /// Gets a reference to the underlying sink.
31    pub fn get_ref(&self) -> &S {
32        &self.inner
33    }
34
35    /// Gets a mutable reference to the underlying sink.
36    pub fn get_mut(&mut self) -> &mut S {
37        &mut self.inner
38    }
39
40    /// Consumes this [`CopyToBytes`], returning the underlying sink.
41    pub fn into_inner(self) -> S {
42        self.inner
43    }
44}
45
46impl<'a, S> Sink<&'a [u8]> for CopyToBytes<S>
47where
48    S: Sink<Bytes>,
49{
50    type Error = S::Error;
51
52    fn poll_ready(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
53        self.project().inner.poll_ready(cx)
54    }
55
56    fn start_send(self: Pin<&mut Self>, item: &'a [u8]) -> Result<(), Self::Error> {
57        self.project()
58            .inner
59            .start_send(Bytes::copy_from_slice(item))
60    }
61
62    fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
63        self.project().inner.poll_flush(cx)
64    }
65
66    fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
67        self.project().inner.poll_close(cx)
68    }
69}
70
71impl<S: Stream> Stream for CopyToBytes<S> {
72    type Item = S::Item;
73    fn poll_next(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Self::Item>> {
74        self.project().inner.poll_next(cx)
75    }
76}