1 | use crate::io::{AsyncSeek, SeekFrom}; |
2 | use futures_core::future::Future; |
3 | use futures_core::task::{Context, Poll}; |
4 | use std::io; |
5 | use std::pin::Pin; |
6 | |
7 | /// Future for the [`seek`](crate::io::AsyncSeekExt::seek) method. |
8 | #[derive (Debug)] |
9 | #[must_use = "futures do nothing unless you `.await` or poll them" ] |
10 | pub struct Seek<'a, S: ?Sized> { |
11 | seek: &'a mut S, |
12 | pos: SeekFrom, |
13 | } |
14 | |
15 | impl<S: ?Sized + Unpin> Unpin for Seek<'_, S> {} |
16 | |
17 | impl<'a, S: AsyncSeek + ?Sized + Unpin> Seek<'a, S> { |
18 | pub(super) fn new(seek: &'a mut S, pos: SeekFrom) -> Self { |
19 | Self { seek, pos } |
20 | } |
21 | } |
22 | |
23 | impl<S: AsyncSeek + ?Sized + Unpin> Future for Seek<'_, S> { |
24 | type Output = io::Result<u64>; |
25 | |
26 | fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { |
27 | let this: &mut Seek<'_, S> = &mut *self; |
28 | Pin::new(&mut this.seek).poll_seek(cx, this.pos) |
29 | } |
30 | } |
31 | |