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use crate::io::driver::{Direction, Handle, Interest, ReadyEvent, ScheduledIo};
use crate::util::slab;
use mio::event::Source;
use std::io;
use std::task::{Context, Poll};
cfg_io_driver! {
#[derive(Debug)]
pub(crate) struct Registration {
handle: Handle,
shared: slab::Ref<ScheduledIo>,
}
}
unsafe impl Send for Registration {}
unsafe impl Sync for Registration {}
impl Registration {
pub(crate) fn new_with_interest_and_handle(
io: &mut impl Source,
interest: Interest,
handle: Handle,
) -> io::Result<Registration> {
let shared = if let Some(inner) = handle.inner() {
inner.add_source(io, interest)?
} else {
return Err(io::Error::new(
io::ErrorKind::Other,
"failed to find event loop",
));
};
Ok(Registration { handle, shared })
}
pub(crate) fn deregister(&mut self, io: &mut impl Source) -> io::Result<()> {
let inner = match self.handle.inner() {
Some(inner) => inner,
None => return Err(io::Error::new(io::ErrorKind::Other, "reactor gone")),
};
inner.deregister_source(io)
}
pub(crate) fn clear_readiness(&self, event: ReadyEvent) {
self.shared.clear_readiness(event);
}
pub(crate) fn poll_read_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<ReadyEvent>> {
self.poll_ready(cx, Direction::Read)
}
pub(crate) fn poll_write_ready(&self, cx: &mut Context<'_>) -> Poll<io::Result<ReadyEvent>> {
self.poll_ready(cx, Direction::Write)
}
pub(crate) fn poll_read_io<R>(
&self,
cx: &mut Context<'_>,
f: impl FnMut() -> io::Result<R>,
) -> Poll<io::Result<R>> {
self.poll_io(cx, Direction::Read, f)
}
pub(crate) fn poll_write_io<R>(
&self,
cx: &mut Context<'_>,
f: impl FnMut() -> io::Result<R>,
) -> Poll<io::Result<R>> {
self.poll_io(cx, Direction::Write, f)
}
fn poll_ready(
&self,
cx: &mut Context<'_>,
direction: Direction,
) -> Poll<io::Result<ReadyEvent>> {
let coop = ready!(crate::coop::poll_proceed(cx));
let ev = ready!(self.shared.poll_readiness(cx, direction));
if self.handle.inner().is_none() {
return Poll::Ready(Err(gone()));
}
coop.made_progress();
Poll::Ready(Ok(ev))
}
fn poll_io<R>(
&self,
cx: &mut Context<'_>,
direction: Direction,
mut f: impl FnMut() -> io::Result<R>,
) -> Poll<io::Result<R>> {
loop {
let ev = ready!(self.poll_ready(cx, direction))?;
match f() {
Ok(ret) => {
return Poll::Ready(Ok(ret));
}
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
self.clear_readiness(ev);
}
Err(e) => return Poll::Ready(Err(e)),
}
}
}
pub(crate) fn try_io<R>(
&self,
interest: Interest,
f: impl FnOnce() -> io::Result<R>,
) -> io::Result<R> {
let ev = self.shared.ready_event(interest);
if ev.ready.is_empty() {
return Err(io::ErrorKind::WouldBlock.into());
}
match f() {
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
self.clear_readiness(ev);
Err(io::ErrorKind::WouldBlock.into())
}
res => res,
}
}
}
fn gone() -> io::Error {
io::Error::new(io::ErrorKind::Other, "IO driver has terminated")
}
cfg_io_readiness! {
impl Registration {
pub(crate) async fn readiness(&self, interest: Interest) -> io::Result<ReadyEvent> {
use std::future::Future;
use std::pin::Pin;
let fut = self.shared.readiness(interest);
pin!(fut);
crate::future::poll_fn(|cx| {
if self.handle.inner().is_none() {
return Poll::Ready(Err(io::Error::new(io::ErrorKind::Other, "reactor gone")));
}
Pin::new(&mut fut).poll(cx).map(Ok)
}).await
}
pub(crate) async fn async_io<R>(&self, interest: Interest, mut f: impl FnMut() -> io::Result<R>) -> io::Result<R> {
loop {
let event = self.readiness(interest).await?;
match f() {
Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
self.clear_readiness(event);
}
x => return x,
}
}
}
}
}