multipart_write/stream/
collect_complete.rs1use crate::{FusedMultipartWrite, MultipartWrite};
2
3use futures_core::future::{FusedFuture, Future};
4use futures_core::ready;
5use futures_core::stream::Stream;
6use std::fmt::{self, Debug, Formatter};
7use std::pin::Pin;
8use std::task::{Context, Poll};
9
10pin_project_lite::pin_project! {
11 #[must_use = "futures do nothing unless polled"]
15 pub struct CollectComplete<St: Stream, Wr> {
16 #[pin]
17 writer: Wr,
18 #[pin]
19 stream: Option<St>,
20 buffered: Option<St::Item>,
21 is_terminated: bool,
22 }
23}
24
25impl<St: Stream, Wr> CollectComplete<St, Wr> {
26 pub(super) fn new(stream: St, writer: Wr) -> Self {
27 Self {
28 writer,
29 stream: Some(stream),
30 buffered: None,
31 is_terminated: false,
32 }
33 }
34}
35
36impl<St, Wr> FusedFuture for CollectComplete<St, Wr>
37where
38 St: Stream,
39 Wr: FusedMultipartWrite<St::Item>,
40{
41 fn is_terminated(&self) -> bool {
42 self.writer.is_terminated() || self.is_terminated
43 }
44}
45
46impl<St, Wr> Future for CollectComplete<St, Wr>
47where
48 St: Stream,
49 Wr: MultipartWrite<St::Item>,
50{
51 type Output = Result<Wr::Output, Wr::Error>;
52
53 fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
54 let mut this = self.project();
55
56 loop {
57 if this.buffered.is_some() {
58 loop {
59 match this.writer.as_mut().poll_ready(cx) {
60 Poll::Ready(Ok(())) => break,
61 Poll::Ready(Err(e)) => return Poll::Ready(Err(e)),
62 Poll::Pending => match this.writer.as_mut().poll_flush(cx)? {
63 Poll::Pending => return Poll::Pending,
64 Poll::Ready(()) => {}
65 },
66 }
67 }
68
69 let _ = this
70 .writer
71 .as_mut()
72 .start_send(this.buffered.take().unwrap())?;
73 }
74
75 let Some(st) = this.stream.as_mut().as_pin_mut() else {
76 ready!(this.writer.as_mut().poll_flush(cx))?;
77 let output = ready!(this.writer.as_mut().poll_complete(cx));
78 *this.is_terminated = true;
79 return Poll::Ready(output);
80 };
81
82 match ready!(st.poll_next(cx)) {
83 Some(it) => *this.buffered = Some(it),
84 None => this.stream.set(None),
85 }
86 }
87 }
88}
89
90impl<St, Wr> Debug for CollectComplete<St, Wr>
91where
92 St: Stream + Debug,
93 St::Item: Debug,
94 Wr: Debug,
95{
96 fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
97 f.debug_struct("CollectComplete")
98 .field("writer", &self.writer)
99 .field("stream", &self.stream)
100 .field("buffered", &self.buffered)
101 .field("is_terminated", &self.is_terminated)
102 .finish()
103 }
104}