Files
h2/src/proto/settings.rs
Carl Lerche fa21970656 Much work
2017-06-23 13:13:50 -07:00

129 lines
3.4 KiB
Rust

use ConnectionError;
use frame::{self, Frame};
use proto::ReadySink;
use futures::*;
pub struct Settings<T> {
// Upstream transport
inner: T,
// Our settings
local: frame::SettingSet,
// Peer settings
remote: frame::SettingSet,
// Number of acks remaining to send to the peer
remaining_acks: usize,
// True when the local settings must be flushed to the remote
is_dirty: bool,
}
/*
* TODO:
* - Settings ack timeout for connection error
*/
impl<T> Settings<T>
where T: Stream<Item = Frame, Error = ConnectionError>,
T: Sink<SinkItem = Frame, SinkError = ConnectionError>,
{
pub fn new(inner: T, local: frame::SettingSet) -> Settings<T> {
Settings {
inner: inner,
local: local,
remote: frame::SettingSet::default(),
remaining_acks: 0,
is_dirty: true,
}
}
fn try_send_pending(&mut self) -> Poll<(), ConnectionError> {
if self.is_dirty {
let frame = frame::Settings::new(self.local.clone());
try_ready!(self.try_send(frame));
self.is_dirty = false;
}
while self.remaining_acks > 0 {
let frame = frame::Settings::ack().into();
try_ready!(self.try_send(frame));
self.remaining_acks -= 1;
}
Ok(Async::Ready(()))
}
fn try_send(&mut self, item: frame::Settings) -> Poll<(), ConnectionError> {
if let AsyncSink::NotReady(_) = try!(self.inner.start_send(item.into())) {
// Ensure that call to `poll_complete` guarantee is called to satisfied
try!(self.inner.poll_complete());
return Ok(Async::NotReady);
}
Ok(Async::Ready(()))
}
}
impl<T> Stream for Settings<T>
where T: Stream<Item = Frame, Error = ConnectionError>,
T: Sink<SinkItem = Frame, SinkError = ConnectionError>,
{
type Item = Frame;
type Error = ConnectionError;
fn poll(&mut self) -> Poll<Option<Frame>, ConnectionError> {
self.inner.poll()
}
}
impl<T> Sink for Settings<T>
where T: Stream<Item = Frame, Error = ConnectionError>,
T: Sink<SinkItem = Frame, SinkError = ConnectionError>,
{
type SinkItem = Frame;
type SinkError = ConnectionError;
fn start_send(&mut self, item: Frame) -> StartSend<Frame, ConnectionError> {
// Settings frames take priority, so `item` cannot be sent if there are
// any pending acks OR the local settings have been changed w/o sending
// an associated frame.
if !try!(self.try_send_pending()).is_ready() {
return Ok(AsyncSink::NotReady(item));
}
self.inner.start_send(item)
}
fn poll_complete(&mut self) -> Poll<(), ConnectionError> {
self.inner.poll_complete()
}
fn close(&mut self) -> Poll<(), ConnectionError> {
if !try!(self.try_send_pending()).is_ready() {
return Ok(Async::NotReady);
}
self.inner.close()
}
}
impl<T> ReadySink for Settings<T>
where T: Stream<Item = Frame, Error = ConnectionError>,
T: Sink<SinkItem = Frame, SinkError = ConnectionError>,
T: ReadySink,
{
fn poll_ready(&mut self) -> Poll<(), ConnectionError> {
if try!(self.try_send_pending()).is_ready() {
return self.inner.poll_ready();
}
Ok(Async::NotReady)
}
}