blob: 279b1a3bc7d38ccf50bc85214bcc76c6228fbb5b [file] [log] [blame]
#![allow(deprecated)]
use std::fmt;
use AsyncRead;
use codec::Decoder;
use super::framed::Fuse;
use futures::{Async, Poll, Stream, Sink, StartSend};
use bytes::BytesMut;
/// A `Stream` of messages decoded from an `AsyncRead`.
pub struct FramedRead<T, D> {
inner: FramedRead2<Fuse<T, D>>,
}
pub struct FramedRead2<T> {
inner: T,
eof: bool,
is_readable: bool,
buffer: BytesMut,
}
const INITIAL_CAPACITY: usize = 8 * 1024;
// ===== impl FramedRead =====
impl<T, D> FramedRead<T, D>
where T: AsyncRead,
D: Decoder,
{
/// Creates a new `FramedRead` with the given `decoder`.
pub fn new(inner: T, decoder: D) -> FramedRead<T, D> {
FramedRead {
inner: framed_read2(Fuse(inner, decoder)),
}
}
}
impl<T, D> FramedRead<T, D> {
/// Returns a reference to the underlying I/O stream wrapped by
/// `FramedRead`.
///
/// Note that care should be taken to not tamper with the underlying stream
/// of data coming in as it may corrupt the stream of frames otherwise
/// being worked with.
pub fn get_ref(&self) -> &T {
&self.inner.inner.0
}
/// Returns a mutable reference to the underlying I/O stream wrapped by
/// `FramedRead`.
///
/// Note that care should be taken to not tamper with the underlying stream
/// of data coming in as it may corrupt the stream of frames otherwise
/// being worked with.
pub fn get_mut(&mut self) -> &mut T {
&mut self.inner.inner.0
}
/// Consumes the `FramedRead`, returning its underlying I/O stream.
///
/// Note that care should be taken to not tamper with the underlying stream
/// of data coming in as it may corrupt the stream of frames otherwise
/// being worked with.
pub fn into_inner(self) -> T {
self.inner.inner.0
}
/// Returns a reference to the underlying decoder.
pub fn decoder(&self) -> &D {
&self.inner.inner.1
}
/// Returns a mutable reference to the underlying decoder.
pub fn decoder_mut(&mut self) -> &mut D {
&mut self.inner.inner.1
}
}
impl<T, D> Stream for FramedRead<T, D>
where T: AsyncRead,
D: Decoder,
{
type Item = D::Item;
type Error = D::Error;
fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
self.inner.poll()
}
}
impl<T, D> Sink for FramedRead<T, D>
where T: Sink,
{
type SinkItem = T::SinkItem;
type SinkError = T::SinkError;
fn start_send(&mut self,
item: Self::SinkItem)
-> StartSend<Self::SinkItem, Self::SinkError>
{
self.inner.inner.0.start_send(item)
}
fn poll_complete(&mut self) -> Poll<(), Self::SinkError> {
self.inner.inner.0.poll_complete()
}
fn close(&mut self) -> Poll<(), Self::SinkError> {
self.inner.inner.0.close()
}
}
impl<T, D> fmt::Debug for FramedRead<T, D>
where T: fmt::Debug,
D: fmt::Debug,
{
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
f.debug_struct("FramedRead")
.field("inner", &self.inner.inner.0)
.field("decoder", &self.inner.inner.1)
.field("eof", &self.inner.eof)
.field("is_readable", &self.inner.is_readable)
.field("buffer", &self.inner.buffer)
.finish()
}
}
// ===== impl FramedRead2 =====
pub fn framed_read2<T>(inner: T) -> FramedRead2<T> {
FramedRead2 {
inner: inner,
eof: false,
is_readable: false,
buffer: BytesMut::with_capacity(INITIAL_CAPACITY),
}
}
pub fn framed_read2_with_buffer<T>(inner: T, mut buf: BytesMut) -> FramedRead2<T> {
if buf.capacity() < INITIAL_CAPACITY {
let bytes_to_reserve = INITIAL_CAPACITY - buf.capacity();
buf.reserve(bytes_to_reserve);
}
FramedRead2 {
inner: inner,
eof: false,
is_readable: buf.len() > 0,
buffer: buf,
}
}
impl<T> FramedRead2<T> {
pub fn get_ref(&self) -> &T {
&self.inner
}
pub fn into_inner(self) -> T {
self.inner
}
pub fn into_parts(self) -> (T, BytesMut) {
(self.inner, self.buffer)
}
pub fn get_mut(&mut self) -> &mut T {
&mut self.inner
}
}
impl<T> Stream for FramedRead2<T>
where T: AsyncRead + Decoder,
{
type Item = T::Item;
type Error = T::Error;
fn poll(&mut self) -> Poll<Option<Self::Item>, Self::Error> {
loop {
// Repeatedly call `decode` or `decode_eof` as long as it is
// "readable". Readable is defined as not having returned `None`. If
// the upstream has returned EOF, and the decoder is no longer
// readable, it can be assumed that the decoder will never become
// readable again, at which point the stream is terminated.
if self.is_readable {
if self.eof {
let frame = try!(self.inner.decode_eof(&mut self.buffer));
return Ok(Async::Ready(frame));
}
trace!("attempting to decode a frame");
if let Some(frame) = try!(self.inner.decode(&mut self.buffer)) {
trace!("frame decoded from buffer");
return Ok(Async::Ready(Some(frame)));
}
self.is_readable = false;
}
assert!(!self.eof);
// Otherwise, try to read more data and try again. Make sure we've
// got room for at least one byte to read to ensure that we don't
// get a spurious 0 that looks like EOF
self.buffer.reserve(1);
if 0 == try_ready!(self.inner.read_buf(&mut self.buffer)) {
self.eof = true;
}
self.is_readable = true;
}
}
}