1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64

use std::io::{self, Read, Write};

use futures::{Async, Poll};
use futures::sync::BiLock;

use {AsyncRead, AsyncWrite};

/// The readable half of an object returned from `AsyncRead::split`.
#[derive(Debug)]
pub struct ReadHalf<T> {
    handle: BiLock<T>,
}

/// The writable half of an object returned from `AsyncRead::split`.
#[derive(Debug)]
pub struct WriteHalf<T> {
    handle: BiLock<T>,
}

pub fn split<T: AsyncRead + AsyncWrite>(t: T) -> (ReadHalf<T>, WriteHalf<T>) {
    let (a, b) = BiLock::new(t);
    (ReadHalf { handle: a }, WriteHalf { handle: b })
}

fn would_block() -> io::Error {
    io::Error::new(io::ErrorKind::WouldBlock, "would block")
}

impl<T: AsyncRead> Read for ReadHalf<T> {
    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
        match self.handle.poll_lock() {
            Async::Ready(mut l) => l.read(buf),
            Async::NotReady => Err(would_block()),
        }
    }
}

impl<T: AsyncRead> AsyncRead for ReadHalf<T> {
}

impl<T: AsyncWrite> Write for WriteHalf<T> {
    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
        match self.handle.poll_lock() {
            Async::Ready(mut l) => l.write(buf),
            Async::NotReady => Err(would_block()),
        }
    }

    fn flush(&mut self) -> io::Result<()> {
        match self.handle.poll_lock() {
            Async::Ready(mut l) => l.flush(),
            Async::NotReady => Err(would_block()),
        }
    }
}

impl<T: AsyncWrite> AsyncWrite for WriteHalf<T> {
    fn shutdown(&mut self) -> Poll<(), io::Error> {
        match self.handle.poll_lock() {
            Async::Ready(mut l) => l.shutdown(),
            Async::NotReady => Err(would_block()),
        }
    }
}