sel4_async_io/
lib.rs

Help
1//
2// Copyright 2024, Colias Group, LLC
3// Copyright 2024, Embedded devices Working Group
4//
5// SPDX-License-Identifier: MIT OR Apache-2.0
6//
7
8// TODO use Pin
9
10#![no_std]
11
12use core::future::{poll_fn, Future};
13use core::pin::{pin, Pin};
14use core::task::{Context, Poll};
15
16use embedded_io_async as eio;
17
18pub use embedded_io_async::{Error, ErrorKind, ErrorType};
19
20pub trait Read: ErrorType {
21    fn poll_read(
22        self: Pin<&mut Self>,
23        cx: &mut Context<'_>,
24        buf: &mut [u8],
25    ) -> Poll<Result<usize, Self::Error>>;
26}
27
28pub trait Write: ErrorType {
29    fn poll_write(
30        self: Pin<&mut Self>,
31        cx: &mut Context<'_>,
32        buf: &[u8],
33    ) -> Poll<Result<usize, Self::Error>>;
34
35    fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
36        Poll::Ready(Ok(()))
37    }
38}
39
40impl<T: Read + Unpin> Read for &mut T {
41    fn poll_read(
42        self: Pin<&mut Self>,
43        cx: &mut Context<'_>,
44        buf: &mut [u8],
45    ) -> Poll<Result<usize, Self::Error>> {
46        T::poll_read(Pin::new(*Pin::into_inner(self)), cx, buf)
47    }
48}
49
50impl<T: Write + Unpin> Write for &mut T {
51    fn poll_write(
52        self: Pin<&mut Self>,
53        cx: &mut Context<'_>,
54        buf: &[u8],
55    ) -> Poll<Result<usize, Self::Error>> {
56        T::poll_write(Pin::new(*Pin::into_inner(self)), cx, buf)
57    }
58
59    fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
60        T::poll_flush(Pin::new(*Pin::into_inner(self)), cx)
61    }
62}
63
64#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
65pub struct EmbeddedIOAsyncAdapter<T>(pub T);
66
67impl<T: ErrorType> ErrorType for EmbeddedIOAsyncAdapter<T> {
68    type Error = T::Error;
69}
70
71impl<T> eio::Read for EmbeddedIOAsyncAdapter<T>
72where
73    T: Read + Unpin,
74{
75    async fn read(&mut self, buf: &mut [u8]) -> Result<usize, Self::Error> {
76        poll_fn(|cx| Pin::new(&mut self.0).poll_read(cx, buf)).await
77    }
78}
79
80impl<T> eio::Write for EmbeddedIOAsyncAdapter<T>
81where
82    T: Write + Unpin,
83{
84    async fn write(&mut self, buf: &[u8]) -> Result<usize, Self::Error> {
85        poll_fn(|cx| Pin::new(&mut self.0).poll_write(cx, buf)).await
86    }
87
88    async fn flush(&mut self) -> Result<(), Self::Error> {
89        poll_fn(|cx| Pin::new(&mut self.0).poll_flush(cx)).await
90    }
91}
92
93pub trait ReadCancelSafe: eio::Read {}
94pub trait FlushCancelSafe: eio::Write {}
95pub trait WriteCancelSafe: FlushCancelSafe {}
96
97impl<T: Read + Unpin> ReadCancelSafe for EmbeddedIOAsyncAdapter<T> {}
98impl<T: Write + Unpin> FlushCancelSafe for EmbeddedIOAsyncAdapter<T> {}
99impl<T: Write + Unpin> WriteCancelSafe for EmbeddedIOAsyncAdapter<T> {}
100
101impl<T> Read for EmbeddedIOAsyncAdapter<T>
102where
103    T: eio::Read + ReadCancelSafe + Unpin,
104{
105    fn poll_read(
106        mut self: Pin<&mut Self>,
107        cx: &mut Context<'_>,
108        buf: &mut [u8],
109    ) -> Poll<Result<usize, Self::Error>> {
110        pin!(self.0.read(buf)).poll(cx)
111    }
112}
113
114impl<T> Write for EmbeddedIOAsyncAdapter<T>
115where
116    T: eio::Write + WriteCancelSafe + Unpin,
117{
118    fn poll_write(
119        mut self: Pin<&mut Self>,
120        cx: &mut Context<'_>,
121        buf: &[u8],
122    ) -> Poll<Result<usize, Self::Error>> {
123        pin!(self.0.write(buf)).poll(cx)
124    }
125
126    fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
127        pin!(self.0.flush()).poll(cx)
128    }
129}
130
131#[derive(Debug, Copy, Clone, Eq, PartialEq, Ord, PartialOrd, Hash)]
132pub struct EmbeddedIOAsyncAdapterUsingReady<T>(pub T);
133
134impl<T: ErrorType> ErrorType for EmbeddedIOAsyncAdapterUsingReady<T> {
135    type Error = T::Error;
136}
137
138impl<T> Read for EmbeddedIOAsyncAdapterUsingReady<T>
139where
140    T: eio::Read + eio::ReadReady + Unpin,
141{
142    fn poll_read(
143        mut self: Pin<&mut Self>,
144        cx: &mut Context<'_>,
145        buf: &mut [u8],
146    ) -> Poll<Result<usize, Self::Error>> {
147        if self.0.read_ready()? {
148            match pin!(self.0.read(buf)).poll(cx) {
149                Poll::Ready(r) => Poll::Ready(r),
150                Poll::Pending => unreachable!(),
151            }
152        } else {
153            Poll::Pending
154        }
155    }
156}
157
158impl<T> Write for EmbeddedIOAsyncAdapterUsingReady<T>
159where
160    T: eio::Write + eio::WriteReady + FlushCancelSafe + Unpin,
161{
162    fn poll_write(
163        mut self: Pin<&mut Self>,
164        cx: &mut Context<'_>,
165        buf: &[u8],
166    ) -> Poll<Result<usize, Self::Error>> {
167        if self.0.write_ready()? {
168            match pin!(self.0.write(buf)).poll(cx) {
169                Poll::Ready(r) => Poll::Ready(r),
170                Poll::Pending => unreachable!(),
171            }
172        } else {
173            Poll::Pending
174        }
175    }
176
177    fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<(), Self::Error>> {
178        pin!(self.0.flush()).poll(cx)
179    }
180}
sel4_async_io/lib.rs

sel4_async_io/
lib.rs
