Files
reqwest-impersonate/src/wait.rs
2019-08-16 12:59:55 -07:00

104 lines
2.2 KiB
Rust

use std::sync::Arc;
use std::thread;
use std::time::{Duration, Instant};
use futures::{Async, Future, Poll, Stream};
use futures::executor::{self, Notify};
use tokio_executor::{enter, EnterError};
pub(crate) fn timeout<F>(fut: F, timeout: Option<Duration>) -> Result<F::Item, Waited<F::Error>>
where
F: Future,
{
let mut spawn = executor::spawn(fut);
block_on(timeout, |notify| {
spawn.poll_future_notify(notify, 0)
})
}
pub(crate) fn stream<S>(stream: S, timeout: Option<Duration>) -> WaitStream<S>
where S: Stream {
WaitStream {
stream: executor::spawn(stream),
timeout,
}
}
#[derive(Debug)]
pub(crate) enum Waited<E> {
TimedOut,
Executor(EnterError),
Inner(E),
}
impl<E> From<E> for Waited<E> {
fn from(err: E) -> Waited<E> {
Waited::Inner(err)
}
}
pub(crate) struct WaitStream<S> {
stream: executor::Spawn<S>,
timeout: Option<Duration>,
}
impl<S> Iterator for WaitStream<S>
where S: Stream {
type Item = Result<S::Item, Waited<S::Error>>;
fn next(&mut self) -> Option<Self::Item> {
let res = block_on(self.timeout, |notify| {
self.stream.poll_stream_notify(notify, 0)
});
match res {
Ok(Some(val)) => Some(Ok(val)),
Ok(None) => None,
Err(err) => Some(Err(err)),
}
}
}
struct ThreadNotify {
thread: thread::Thread,
}
impl Notify for ThreadNotify {
fn notify(&self, _id: usize) {
self.thread.unpark();
}
}
fn block_on<F, U, E>(timeout: Option<Duration>, mut poll: F) -> Result<U, Waited<E>>
where
F: FnMut(&Arc<ThreadNotify>) -> Poll<U, E>,
{
let _entered = enter().map_err(Waited::Executor)?;
let deadline = timeout.map(|d| {
Instant::now() + d
});
let notify = Arc::new(ThreadNotify {
thread: thread::current(),
});
loop {
match poll(&notify)? {
Async::Ready(val) => return Ok(val),
Async::NotReady => {}
}
if let Some(deadline) = deadline {
let now = Instant::now();
if now >= deadline {
return Err(Waited::TimedOut);
}
thread::park_timeout(deadline - now);
} else {
thread::park();
}
}
}