multipart_write/write/
feed.rs

1use crate::{FusedMultipartWrite, MultipartWrite};
2
3use futures_core::future::{FusedFuture, Future};
4use futures_core::ready;
5use std::fmt::{self, Debug, Formatter};
6use std::pin::Pin;
7use std::task::{Context, Poll};
8
9/// Future for [`feed`](super::MultipartWriteExt::feed).
10#[must_use = "futures do nothing unless polled"]
11pub struct Feed<'a, Wr: ?Sized, Part> {
12    writer: &'a mut Wr,
13    buffered: Option<Part>,
14}
15
16impl<Wr: ?Sized + Unpin, Part> Unpin for Feed<'_, Wr, Part> {}
17
18impl<'a, Wr: ?Sized + MultipartWrite<Part> + Unpin, Part> Feed<'a, Wr, Part> {
19    pub(super) fn new(writer: &'a mut Wr, part: Part) -> Self {
20        Self {
21            writer,
22            buffered: Some(part),
23        }
24    }
25
26    pub(super) fn writer_pin_mut(&mut self) -> Pin<&mut Wr> {
27        Pin::new(self.writer)
28    }
29
30    pub(super) fn is_part_pending(&self) -> bool {
31        self.buffered.is_some()
32    }
33}
34
35impl<Wr, Part> FusedFuture for Feed<'_, Wr, Part>
36where
37    Wr: FusedMultipartWrite<Part> + Unpin,
38{
39    fn is_terminated(&self) -> bool {
40        self.writer.is_terminated()
41    }
42}
43
44impl<Wr: ?Sized + MultipartWrite<Part> + Unpin, Part> Future for Feed<'_, Wr, Part> {
45    type Output = Result<Wr::Ret, Wr::Error>;
46
47    fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
48        let this = &mut *self;
49
50        ready!(Pin::new(&mut this.writer).poll_ready(cx))?;
51        let part = this.buffered.take().expect("polled Feed after completion");
52        let ret = Pin::new(&mut this.writer).start_send(part);
53        Poll::Ready(ret)
54    }
55}
56
57impl<Wr: Debug, Part: Debug> Debug for Feed<'_, Wr, Part> {
58    fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
59        f.debug_struct("Feed")
60            .field("writer", &self.writer)
61            .field("buffered", &self.buffered)
62            .finish()
63    }
64}
multipart_write/write/feed.rs

multipart_write/write/
feed.rs
