embedded_platform/io/
write_all.rs

1use core::future;
2use core::mem;
3use core::pin;
4use core::task;
5
6#[derive(Debug)]
7#[must_use = "futures do nothing unless you `.await` or poll them"]
8pub struct WriteAll<'a, A: ?Sized> {
9    writer: &'a mut A,
10    buffer: &'a [u8],
11}
12
13pub(crate) fn write_all<'a, A>(writer: &'a mut A, buffer: &'a [u8]) -> WriteAll<'a, A>
14where
15    A: super::Write + Unpin + ?Sized,
16{
17    WriteAll { writer, buffer }
18}
19
20impl<A> future::Future for WriteAll<'_, A>
21where
22    A: super::Write + Unpin + ?Sized,
23{
24    type Output = Result<(), A::Error>;
25
26    fn poll(mut self: pin::Pin<&mut Self>, cx: &mut task::Context<'_>) -> task::Poll<Self::Output> {
27        use super::Write;
28        use super::WriteError;
29
30        let this = &mut *self;
31        while !this.buffer.is_empty() {
32            let n = futures::ready!(pin::Pin::new(&mut this.writer).poll_write(cx, this.buffer))?;
33            {
34                let (_, rest) = mem::replace(&mut this.buffer, &[]).split_at(n);
35                this.buffer = rest;
36            }
37            if n == 0 {
38                return task::Poll::Ready(Err(A::Error::write_zero()));
39            }
40        }
41
42        task::Poll::Ready(Ok(()))
43    }
44}
embedded_platform/io/write_all.rs

embedded_platform/io/
write_all.rs
