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tcp: update API documentation (#1392)
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carllerche committed Aug 5, 2019
1 parent 6cbe3d4 commit 6d8cc4e
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Showing 5 changed files with 294 additions and 462 deletions.
6 changes: 3 additions & 3 deletions tokio-io/Cargo.toml
Expand Up @@ -21,6 +21,9 @@ Core I/O primitives for asynchronous I/O in Rust.
categories = ["asynchronous"]
publish = false

[features]
util = ["memchr"]

[dependencies]
bytes = "0.4.7"
log = "0.4"
Expand All @@ -32,6 +35,3 @@ pin-utils = "0.1.0-alpha.4"
tokio = { version = "0.2.0", path = "../tokio" }
futures-util-preview = "0.3.0-alpha.17"
tokio-test = { version = "0.2.0", path = "../tokio-test" }

[features]
util = ["memchr"]
42 changes: 28 additions & 14 deletions tokio-reactor/src/poll_evented.rs
Expand Up @@ -52,19 +52,33 @@ use tokio_io::{AsyncRead, AsyncWrite};
/// [`TcpListener`] implements poll_accept by using [`poll_read_ready`] and
/// [`clear_read_ready`].
///
/// ```rust,ignore
/// pub fn poll_accept(&mut self) -> Poll<(net::TcpStream, SocketAddr), io::Error> {
/// let ready = Ready::readable();
/// ```rust
/// use tokio_reactor::PollEvented;
///
/// try_ready!(self.poll_evented.poll_read_ready(ready));
/// use futures_core::ready;
/// use mio::Ready;
/// use mio::net::{TcpStream, TcpListener};
/// use std::io;
/// use std::task::{Context, Poll};
///
/// match self.poll_evented.get_ref().accept_std() {
/// Ok(pair) => Ok(Async::Ready(pair)),
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// self.poll_evented.clear_read_ready(ready);
/// Ok(Async::NotReady)
/// struct MyListener {
/// poll_evented: PollEvented<TcpListener>,
/// }
///
/// impl MyListener {
/// pub fn poll_accept(&mut self, cx: &mut Context<'_>) -> Poll<Result<TcpStream, io::Error>> {
/// let ready = Ready::readable();
///
/// ready!(self.poll_evented.poll_read_ready(cx, ready))?;
///
/// match self.poll_evented.get_ref().accept() {
/// Ok((socket, _)) => Poll::Ready(Ok(socket)),
/// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => {
/// self.poll_evented.clear_read_ready(cx, ready);
/// Poll::Pending
/// }
/// Err(e) => Poll::Ready(Err(e)),
/// }
/// Err(e) => Err(e),
/// }
/// }
/// ```
Expand Down Expand Up @@ -209,8 +223,8 @@ where
/// `writable`. HUP is always implicitly included on platforms that support
/// it.
///
/// If the resource is not ready for a read then `Async::NotReady` is
/// returned and the current task is notified once a new event is received.
/// If the resource is not ready for a read then `Poll::Pending` is returned
/// and the current task is notified once a new event is received.
///
/// The I/O resource will remain in a read-ready state until readiness is
/// cleared by calling [`clear_read_ready`].
Expand Down Expand Up @@ -241,8 +255,8 @@ where
/// Clears the I/O resource's read readiness state and registers the current
/// task to be notified once a read readiness event is received.
///
/// After calling this function, `poll_read_ready` will return `NotReady`
/// until a new read readiness event has been received.
/// After calling this function, `poll_read_ready` will return
/// `Poll::Pending` until a new read readiness event has been received.
///
/// The `mask` argument specifies the readiness bits to clear. This may not
/// include `writable` or `hup`.
Expand Down
20 changes: 10 additions & 10 deletions tokio-reactor/src/registration.rs
Expand Up @@ -263,15 +263,15 @@ impl Registration {
///
/// There are several possible return values:
///
/// * `Ok(Async::Ready(readiness))` means that the I/O resource has received
/// * `Poll::Ready(Ok(readiness))` means that the I/O resource has received
/// a new readiness event. The readiness value is included.
///
/// * `Ok(NotReady)` means that no new readiness events have been received
/// * `Poll::Pending` means that no new readiness events have been received
/// since the last call to `poll_read_ready`.
///
/// * `Err(err)` means that the registration has encountered an error. This
/// error either represents a permanent internal error **or** the fact
/// that [`register`] was not called first.
/// * `Poll::Ready(Err(err))` means that the registration has encountered an
/// error. This error either represents a permanent internal error **or**
/// the fact that [`register`] was not called first.
///
/// [`register`]: #method.register
/// [edge-triggered]: https://docs.rs/mio/0.6/mio/struct.Poll.html#edge-triggered-and-level-triggered
Expand Down Expand Up @@ -314,15 +314,15 @@ impl Registration {
///
/// There are several possible return values:
///
/// * `Ok(Async::Ready(readiness))` means that the I/O resource has received
/// * `Poll::Ready(Ok(readiness))` means that the I/O resource has received
/// a new readiness event. The readiness value is included.
///
/// * `Ok(NotReady)` means that no new readiness events have been received
/// * `Poll::Pending` means that no new readiness events have been received
/// since the last call to `poll_write_ready`.
///
/// * `Err(err)` means that the registration has encountered an error. This
/// error either represents a permanent internal error **or** the fact
/// that [`register`] was not called first.
/// * `Poll::Ready(Err(err))` means that the registration has encountered an
/// error. This error either represents a permanent internal error **or**
/// the fact that [`register`] was not called first.
///
/// [`register`]: #method.register
/// [edge-triggered]: https://docs.rs/mio/0.6/mio/struct.Poll.html#edge-triggered-and-level-triggered
Expand Down
155 changes: 35 additions & 120 deletions tokio-tcp/src/listener.rs
Expand Up @@ -18,26 +18,22 @@ use tokio_reactor::{Handle, PollEvented};
/// # Examples
///
/// ```no_run
/// use futures::stream::Stream;
/// use std::net::SocketAddr;
/// use tokio::net::{TcpListener, TcpStream};
/// #![feature(async_await)]
///
/// fn process_socket(socket: TcpStream) {
/// // ...
/// }
/// use tokio::net::TcpListener;
/// use std::error::Error;
/// # async fn process_socket<T>(socket: T) {}
///
/// let addr = "127.0.0.1:8080".parse::<SocketAddr>()?;
/// let listener = TcpListener::bind(&addr)?;
/// #[tokio::main]
/// async fn main() -> Result<(), Box<dyn Error>> {
/// let addr = "127.0.0.1:8080".parse()?;
/// let mut listener = TcpListener::bind(&addr)?;
///
/// // accept connections and process them
/// tokio::run(listener.incoming()
/// .map_err(|e| eprintln!("failed to accept socket; error = {:?}", e))
/// .for_each(|socket| {
/// loop {
/// let (socket, _) = listener.accept().await?;
/// process_socket(socket);
/// Ok(())
/// })
/// );
/// # Ok::<_, Box<dyn std::error::Error>>(())
/// }
/// }
/// ```
pub struct TcpListener {
io: PollEvented<mio::net::TcpListener>,
Expand All @@ -64,42 +60,38 @@ impl TcpListener {
Ok(TcpListener::new(l))
}

/// Attempt to accept a connection and create a new connected `TcpStream` if
/// successful.
///
/// Note that typically for simple usage it's easier to treat incoming
/// connections as a `Stream` of `TcpStream`s with the `incoming` method
/// below.
///
/// # Return
///
/// On success, returns `Ok(Async::Ready((socket, addr)))`.
///
/// If the listener is not ready to accept, the method returns
/// `Ok(Async::NotReady)` and arranges for the current task to receive a
/// notification when the listener becomes ready to accept.
/// Accept a new incoming connection from this listener.
///
/// # Panics
/// This function will yield once a new TCP connection is established. When
/// established, the corresponding [`TcpStream`] and the remote peer's
/// address will be returned.
///
/// This function will panic if called from outside of a task context.
/// [`TcpStream`]: ../struct.TcpStream.html
///
/// # Examples
///
/// ```no_run
/// use std::net::SocketAddr;
/// ```
/// #![feature(async_await)]
///
/// # async fn dox() -> Result<(), Box<dyn std::error::Error>> {
/// use tokio::net::TcpListener;
/// use futures::Async;
///
/// let addr = "127.0.0.1:0".parse::<SocketAddr>()?;
/// let addr = "127.0.0.1:8080".parse()?;
/// let mut listener = TcpListener::bind(&addr)?;
/// match listener.poll_accept() {
/// Ok(Async::Ready((_socket, addr))) => println!("listener ready to accept: {:?}", addr),
/// Ok(Async::NotReady) => println!("listener not ready to accept!"),
/// Err(e) => eprintln!("got an error: {}", e),
/// match listener.accept().await {
/// Ok((_socket, addr)) => println!("new client: {:?}", addr),
/// Err(e) => println!("couldn't get client: {:?}", e),
/// }
/// # Ok::<_, Box<dyn std::error::Error>>(())
/// # Ok(())
/// # }
/// ```
pub fn poll_accept(
#[allow(clippy::needless_lifetimes)] // false positive: https://github.com/rust-lang/rust-clippy/issues/3988
pub async fn accept(&mut self) -> io::Result<(TcpStream, SocketAddr)> {
use async_util::future::poll_fn;
poll_fn(|cx| self.poll_accept(cx)).await
}

pub(crate) fn poll_accept(
&mut self,
cx: &mut Context<'_>,
) -> Poll<io::Result<(TcpStream, SocketAddr)>> {
Expand All @@ -111,62 +103,7 @@ impl TcpListener {
Poll::Ready(Ok((io, addr)))
}

/// Accept a new incoming connection from this listener.
///
/// This function will yield once a new TCP connection is established. When
/// established, the corresponding [`TcpStream`] and the remote peer's
/// address will be returned.
///
/// [`TcpStream`]: ../struct.TcpStream.html
///
/// # Examples
///
/// ```
/// unimplemented!();
/// ```
#[allow(clippy::needless_lifetimes)] // false positive: https://github.com/rust-lang/rust-clippy/issues/3988
pub async fn accept(&mut self) -> io::Result<(TcpStream, SocketAddr)> {
use async_util::future::poll_fn;
poll_fn(|cx| self.poll_accept(cx)).await
}

/// Attempt to accept a connection and create a new connected `TcpStream` if
/// successful.
///
/// This function is the same as `accept` above except that it returns a
/// `std::net::TcpStream` instead of a `tokio::net::TcpStream`. This in turn
/// can then allow for the TCP stream to be associated with a different
/// reactor than the one this `TcpListener` is associated with.
///
/// # Return
///
/// On success, returns `Ok(Async::Ready((socket, addr)))`.
///
/// If the listener is not ready to accept, the method returns
/// `Ok(Async::NotReady)` and arranges for the current task to receive a
/// notification when the listener becomes ready to accept.
///
/// # Panics
///
/// This function will panic if called from outside of a task context.
///
/// # Examples
///
/// ```no_run
/// use std::net::SocketAddr;
/// use tokio::net::TcpListener;
/// use futures::Async;
///
/// let addr = "127.0.0.1:0".parse::<SocketAddr>()?;
/// let mut listener = TcpListener::bind(&addr)?;
/// match listener.poll_accept_std() {
/// Ok(Async::Ready((_socket, addr))) => println!("listener ready to accept: {:?}", addr),
/// Ok(Async::NotReady) => println!("listener not ready to accept!"),
/// Err(e) => eprintln!("got an error: {}", e),
/// }
/// # Ok::<_, Box<dyn std::error::Error>>(())
/// ```
pub fn poll_accept_std(
fn poll_accept_std(
&mut self,
cx: &mut Context<'_>,
) -> Poll<io::Result<(net::TcpStream, SocketAddr)>> {
Expand Down Expand Up @@ -267,28 +204,6 @@ impl TcpListener {
/// necessarily fatal ‒ for example having too many open file descriptors or the other side
/// closing the connection while it waits in an accept queue. These would terminate the stream
/// if not handled in any way.
///
/// If aiming for production, decision what to do about them must be made. The
/// [`tk-listen`](https://crates.io/crates/tk-listen) crate might be of some help.
///
/// # Examples
///
/// ```
/// use tokio::net::TcpListener;
/// use futures::stream::Stream;
/// use std::net::SocketAddr;
///
/// let addr = "127.0.0.1:0".parse::<SocketAddr>()?;
/// let listener = TcpListener::bind(&addr)?;
///
/// listener.incoming()
/// .map_err(|e| eprintln!("failed to accept stream; error = {:?}", e))
/// .for_each(|_socket| {
/// println!("new socket!");
/// Ok(())
/// });
/// # Ok::<_, Box<dyn std::error::Error>>(())
/// ```
#[cfg(feature = "async-traits")]
pub fn incoming(self) -> Incoming {
Incoming::new(self)
Expand Down

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