From 698f8c2f01ea549d77d7dc3338a12e04c11057b9 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Wed, 17 Apr 2024 14:02:58 +0200 Subject: Adding upstream version 1.64.0+dfsg1. Signed-off-by: Daniel Baumann --- library/std/src/net/tcp.rs | 1050 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1050 insertions(+) create mode 100644 library/std/src/net/tcp.rs (limited to 'library/std/src/net/tcp.rs') diff --git a/library/std/src/net/tcp.rs b/library/std/src/net/tcp.rs new file mode 100644 index 000000000..69b72a81c --- /dev/null +++ b/library/std/src/net/tcp.rs @@ -0,0 +1,1050 @@ +#![deny(unsafe_op_in_unsafe_fn)] + +#[cfg(all(test, not(target_os = "emscripten")))] +mod tests; + +use crate::io::prelude::*; + +use crate::fmt; +use crate::io::{self, IoSlice, IoSliceMut}; +use crate::iter::FusedIterator; +use crate::net::{Shutdown, SocketAddr, ToSocketAddrs}; +use crate::sys_common::net as net_imp; +use crate::sys_common::{AsInner, FromInner, IntoInner}; +use crate::time::Duration; + +/// A TCP stream between a local and a remote socket. +/// +/// After creating a `TcpStream` by either [`connect`]ing to a remote host or +/// [`accept`]ing a connection on a [`TcpListener`], data can be transmitted +/// by [reading] and [writing] to it. +/// +/// The connection will be closed when the value is dropped. The reading and writing +/// portions of the connection can also be shut down individually with the [`shutdown`] +/// method. +/// +/// The Transmission Control Protocol is specified in [IETF RFC 793]. +/// +/// [`accept`]: TcpListener::accept +/// [`connect`]: TcpStream::connect +/// [IETF RFC 793]: https://tools.ietf.org/html/rfc793 +/// [reading]: Read +/// [`shutdown`]: TcpStream::shutdown +/// [writing]: Write +/// +/// # Examples +/// +/// ```no_run +/// use std::io::prelude::*; +/// use std::net::TcpStream; +/// +/// fn main() -> std::io::Result<()> { +/// let mut stream = TcpStream::connect("127.0.0.1:34254")?; +/// +/// stream.write(&[1])?; +/// stream.read(&mut [0; 128])?; +/// Ok(()) +/// } // the stream is closed here +/// ``` +#[stable(feature = "rust1", since = "1.0.0")] +pub struct TcpStream(net_imp::TcpStream); + +/// A TCP socket server, listening for connections. +/// +/// After creating a `TcpListener` by [`bind`]ing it to a socket address, it listens +/// for incoming TCP connections. These can be accepted by calling [`accept`] or by +/// iterating over the [`Incoming`] iterator returned by [`incoming`][`TcpListener::incoming`]. +/// +/// The socket will be closed when the value is dropped. +/// +/// The Transmission Control Protocol is specified in [IETF RFC 793]. +/// +/// [`accept`]: TcpListener::accept +/// [`bind`]: TcpListener::bind +/// [IETF RFC 793]: https://tools.ietf.org/html/rfc793 +/// +/// # Examples +/// +/// ```no_run +/// use std::net::{TcpListener, TcpStream}; +/// +/// fn handle_client(stream: TcpStream) { +/// // ... +/// } +/// +/// fn main() -> std::io::Result<()> { +/// let listener = TcpListener::bind("127.0.0.1:80")?; +/// +/// // accept connections and process them serially +/// for stream in listener.incoming() { +/// handle_client(stream?); +/// } +/// Ok(()) +/// } +/// ``` +#[stable(feature = "rust1", since = "1.0.0")] +pub struct TcpListener(net_imp::TcpListener); + +/// An iterator that infinitely [`accept`]s connections on a [`TcpListener`]. +/// +/// This `struct` is created by the [`TcpListener::incoming`] method. +/// See its documentation for more. +/// +/// [`accept`]: TcpListener::accept +#[must_use = "iterators are lazy and do nothing unless consumed"] +#[stable(feature = "rust1", since = "1.0.0")] +#[derive(Debug)] +pub struct Incoming<'a> { + listener: &'a TcpListener, +} + +/// An iterator that infinitely [`accept`]s connections on a [`TcpListener`]. +/// +/// This `struct` is created by the [`TcpListener::into_incoming`] method. +/// See its documentation for more. +/// +/// [`accept`]: TcpListener::accept +#[derive(Debug)] +#[unstable(feature = "tcplistener_into_incoming", issue = "88339")] +pub struct IntoIncoming { + listener: TcpListener, +} + +impl TcpStream { + /// Opens a TCP connection to a remote host. + /// + /// `addr` is an address of the remote host. Anything which implements + /// [`ToSocketAddrs`] trait can be supplied for the address; see this trait + /// documentation for concrete examples. + /// + /// If `addr` yields multiple addresses, `connect` will be attempted with + /// each of the addresses until a connection is successful. If none of + /// the addresses result in a successful connection, the error returned from + /// the last connection attempt (the last address) is returned. + /// + /// # Examples + /// + /// Open a TCP connection to `127.0.0.1:8080`: + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// if let Ok(stream) = TcpStream::connect("127.0.0.1:8080") { + /// println!("Connected to the server!"); + /// } else { + /// println!("Couldn't connect to server..."); + /// } + /// ``` + /// + /// Open a TCP connection to `127.0.0.1:8080`. If the connection fails, open + /// a TCP connection to `127.0.0.1:8081`: + /// + /// ```no_run + /// use std::net::{SocketAddr, TcpStream}; + /// + /// let addrs = [ + /// SocketAddr::from(([127, 0, 0, 1], 8080)), + /// SocketAddr::from(([127, 0, 0, 1], 8081)), + /// ]; + /// if let Ok(stream) = TcpStream::connect(&addrs[..]) { + /// println!("Connected to the server!"); + /// } else { + /// println!("Couldn't connect to server..."); + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn connect(addr: A) -> io::Result { + super::each_addr(addr, net_imp::TcpStream::connect).map(TcpStream) + } + + /// Opens a TCP connection to a remote host with a timeout. + /// + /// Unlike `connect`, `connect_timeout` takes a single [`SocketAddr`] since + /// timeout must be applied to individual addresses. + /// + /// It is an error to pass a zero `Duration` to this function. + /// + /// Unlike other methods on `TcpStream`, this does not correspond to a + /// single system call. It instead calls `connect` in nonblocking mode and + /// then uses an OS-specific mechanism to await the completion of the + /// connection request. + #[stable(feature = "tcpstream_connect_timeout", since = "1.21.0")] + pub fn connect_timeout(addr: &SocketAddr, timeout: Duration) -> io::Result { + net_imp::TcpStream::connect_timeout(addr, timeout).map(TcpStream) + } + + /// Returns the socket address of the remote peer of this TCP connection. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpStream}; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// assert_eq!(stream.peer_addr().unwrap(), + /// SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080))); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn peer_addr(&self) -> io::Result { + self.0.peer_addr() + } + + /// Returns the socket address of the local half of this TCP connection. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::{IpAddr, Ipv4Addr, TcpStream}; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// assert_eq!(stream.local_addr().unwrap().ip(), + /// IpAddr::V4(Ipv4Addr::new(127, 0, 0, 1))); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn local_addr(&self) -> io::Result { + self.0.socket_addr() + } + + /// Shuts down the read, write, or both halves of this connection. + /// + /// This function will cause all pending and future I/O on the specified + /// portions to return immediately with an appropriate value (see the + /// documentation of [`Shutdown`]). + /// + /// # Platform-specific behavior + /// + /// Calling this function multiple times may result in different behavior, + /// depending on the operating system. On Linux, the second call will + /// return `Ok(())`, but on macOS, it will return `ErrorKind::NotConnected`. + /// This may change in the future. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::{Shutdown, TcpStream}; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.shutdown(Shutdown::Both).expect("shutdown call failed"); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn shutdown(&self, how: Shutdown) -> io::Result<()> { + self.0.shutdown(how) + } + + /// Creates a new independently owned handle to the underlying socket. + /// + /// The returned `TcpStream` is a reference to the same stream that this + /// object references. Both handles will read and write the same stream of + /// data, and options set on one stream will be propagated to the other + /// stream. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// let stream_clone = stream.try_clone().expect("clone failed..."); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn try_clone(&self) -> io::Result { + self.0.duplicate().map(TcpStream) + } + + /// Sets the read timeout to the timeout specified. + /// + /// If the value specified is [`None`], then [`read`] calls will block + /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is + /// passed to this method. + /// + /// # Platform-specific behavior + /// + /// Platforms may return a different error code whenever a read times out as + /// a result of setting this option. For example Unix typically returns an + /// error of the kind [`WouldBlock`], but Windows may return [`TimedOut`]. + /// + /// [`read`]: Read::read + /// [`WouldBlock`]: io::ErrorKind::WouldBlock + /// [`TimedOut`]: io::ErrorKind::TimedOut + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_read_timeout(None).expect("set_read_timeout call failed"); + /// ``` + /// + /// An [`Err`] is returned if the zero [`Duration`] is passed to this + /// method: + /// + /// ```no_run + /// use std::io; + /// use std::net::TcpStream; + /// use std::time::Duration; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080").unwrap(); + /// let result = stream.set_read_timeout(Some(Duration::new(0, 0))); + /// let err = result.unwrap_err(); + /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput) + /// ``` + #[stable(feature = "socket_timeout", since = "1.4.0")] + pub fn set_read_timeout(&self, dur: Option) -> io::Result<()> { + self.0.set_read_timeout(dur) + } + + /// Sets the write timeout to the timeout specified. + /// + /// If the value specified is [`None`], then [`write`] calls will block + /// indefinitely. An [`Err`] is returned if the zero [`Duration`] is + /// passed to this method. + /// + /// # Platform-specific behavior + /// + /// Platforms may return a different error code whenever a write times out + /// as a result of setting this option. For example Unix typically returns + /// an error of the kind [`WouldBlock`], but Windows may return [`TimedOut`]. + /// + /// [`write`]: Write::write + /// [`WouldBlock`]: io::ErrorKind::WouldBlock + /// [`TimedOut`]: io::ErrorKind::TimedOut + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_write_timeout(None).expect("set_write_timeout call failed"); + /// ``` + /// + /// An [`Err`] is returned if the zero [`Duration`] is passed to this + /// method: + /// + /// ```no_run + /// use std::io; + /// use std::net::TcpStream; + /// use std::time::Duration; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080").unwrap(); + /// let result = stream.set_write_timeout(Some(Duration::new(0, 0))); + /// let err = result.unwrap_err(); + /// assert_eq!(err.kind(), io::ErrorKind::InvalidInput) + /// ``` + #[stable(feature = "socket_timeout", since = "1.4.0")] + pub fn set_write_timeout(&self, dur: Option) -> io::Result<()> { + self.0.set_write_timeout(dur) + } + + /// Returns the read timeout of this socket. + /// + /// If the timeout is [`None`], then [`read`] calls will block indefinitely. + /// + /// # Platform-specific behavior + /// + /// Some platforms do not provide access to the current timeout. + /// + /// [`read`]: Read::read + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_read_timeout(None).expect("set_read_timeout call failed"); + /// assert_eq!(stream.read_timeout().unwrap(), None); + /// ``` + #[stable(feature = "socket_timeout", since = "1.4.0")] + pub fn read_timeout(&self) -> io::Result> { + self.0.read_timeout() + } + + /// Returns the write timeout of this socket. + /// + /// If the timeout is [`None`], then [`write`] calls will block indefinitely. + /// + /// # Platform-specific behavior + /// + /// Some platforms do not provide access to the current timeout. + /// + /// [`write`]: Write::write + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_write_timeout(None).expect("set_write_timeout call failed"); + /// assert_eq!(stream.write_timeout().unwrap(), None); + /// ``` + #[stable(feature = "socket_timeout", since = "1.4.0")] + pub fn write_timeout(&self) -> io::Result> { + self.0.write_timeout() + } + + /// Receives data on the socket from the remote address to which it is + /// connected, without removing that data from the queue. On success, + /// returns the number of bytes peeked. + /// + /// Successive calls return the same data. This is accomplished by passing + /// `MSG_PEEK` as a flag to the underlying `recv` system call. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8000") + /// .expect("Couldn't connect to the server..."); + /// let mut buf = [0; 10]; + /// let len = stream.peek(&mut buf).expect("peek failed"); + /// ``` + #[stable(feature = "peek", since = "1.18.0")] + pub fn peek(&self, buf: &mut [u8]) -> io::Result { + self.0.peek(buf) + } + + /// Sets the value of the `SO_LINGER` option on this socket. + /// + /// This value controls how the socket is closed when data remains + /// to be sent. If `SO_LINGER` is set, the socket will remain open + /// for the specified duration as the system attempts to send pending data. + /// Otherwise, the system may close the socket immediately, or wait for a + /// default timeout. + /// + /// # Examples + /// + /// ```no_run + /// #![feature(tcp_linger)] + /// + /// use std::net::TcpStream; + /// use std::time::Duration; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_linger(Some(Duration::from_secs(0))).expect("set_linger call failed"); + /// ``` + #[unstable(feature = "tcp_linger", issue = "88494")] + pub fn set_linger(&self, linger: Option) -> io::Result<()> { + self.0.set_linger(linger) + } + + /// Gets the value of the `SO_LINGER` option on this socket. + /// + /// For more information about this option, see [`TcpStream::set_linger`]. + /// + /// # Examples + /// + /// ```no_run + /// #![feature(tcp_linger)] + /// + /// use std::net::TcpStream; + /// use std::time::Duration; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_linger(Some(Duration::from_secs(0))).expect("set_linger call failed"); + /// assert_eq!(stream.linger().unwrap(), Some(Duration::from_secs(0))); + /// ``` + #[unstable(feature = "tcp_linger", issue = "88494")] + pub fn linger(&self) -> io::Result> { + self.0.linger() + } + + /// Sets the value of the `TCP_NODELAY` option on this socket. + /// + /// If set, this option disables the Nagle algorithm. This means that + /// segments are always sent as soon as possible, even if there is only a + /// small amount of data. When not set, data is buffered until there is a + /// sufficient amount to send out, thereby avoiding the frequent sending of + /// small packets. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_nodelay(true).expect("set_nodelay call failed"); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> { + self.0.set_nodelay(nodelay) + } + + /// Gets the value of the `TCP_NODELAY` option on this socket. + /// + /// For more information about this option, see [`TcpStream::set_nodelay`]. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_nodelay(true).expect("set_nodelay call failed"); + /// assert_eq!(stream.nodelay().unwrap_or(false), true); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn nodelay(&self) -> io::Result { + self.0.nodelay() + } + + /// Sets the value for the `IP_TTL` option on this socket. + /// + /// This value sets the time-to-live field that is used in every packet sent + /// from this socket. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_ttl(100).expect("set_ttl call failed"); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn set_ttl(&self, ttl: u32) -> io::Result<()> { + self.0.set_ttl(ttl) + } + + /// Gets the value of the `IP_TTL` option for this socket. + /// + /// For more information about this option, see [`TcpStream::set_ttl`]. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.set_ttl(100).expect("set_ttl call failed"); + /// assert_eq!(stream.ttl().unwrap_or(0), 100); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn ttl(&self) -> io::Result { + self.0.ttl() + } + + /// Gets the value of the `SO_ERROR` option on this socket. + /// + /// This will retrieve the stored error in the underlying socket, clearing + /// the field in the process. This can be useful for checking errors between + /// calls. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpStream; + /// + /// let stream = TcpStream::connect("127.0.0.1:8080") + /// .expect("Couldn't connect to the server..."); + /// stream.take_error().expect("No error was expected..."); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn take_error(&self) -> io::Result> { + self.0.take_error() + } + + /// Moves this TCP stream into or out of nonblocking mode. + /// + /// This will result in `read`, `write`, `recv` and `send` operations + /// becoming nonblocking, i.e., immediately returning from their calls. + /// If the IO operation is successful, `Ok` is returned and no further + /// action is required. If the IO operation could not be completed and needs + /// to be retried, an error with kind [`io::ErrorKind::WouldBlock`] is + /// returned. + /// + /// On Unix platforms, calling this method corresponds to calling `fcntl` + /// `FIONBIO`. On Windows calling this method corresponds to calling + /// `ioctlsocket` `FIONBIO`. + /// + /// # Examples + /// + /// Reading bytes from a TCP stream in non-blocking mode: + /// + /// ```no_run + /// use std::io::{self, Read}; + /// use std::net::TcpStream; + /// + /// let mut stream = TcpStream::connect("127.0.0.1:7878") + /// .expect("Couldn't connect to the server..."); + /// stream.set_nonblocking(true).expect("set_nonblocking call failed"); + /// + /// # fn wait_for_fd() { unimplemented!() } + /// let mut buf = vec![]; + /// loop { + /// match stream.read_to_end(&mut buf) { + /// Ok(_) => break, + /// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => { + /// // wait until network socket is ready, typically implemented + /// // via platform-specific APIs such as epoll or IOCP + /// wait_for_fd(); + /// } + /// Err(e) => panic!("encountered IO error: {e}"), + /// }; + /// }; + /// println!("bytes: {buf:?}"); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> { + self.0.set_nonblocking(nonblocking) + } +} + +// In addition to the `impl`s here, `TcpStream` also has `impl`s for +// `AsFd`/`From`/`Into` and +// `AsRawFd`/`IntoRawFd`/`FromRawFd`, on Unix and WASI, and +// `AsSocket`/`From`/`Into` and +// `AsRawSocket`/`IntoRawSocket`/`FromRawSocket` on Windows. + +#[stable(feature = "rust1", since = "1.0.0")] +impl Read for TcpStream { + fn read(&mut self, buf: &mut [u8]) -> io::Result { + self.0.read(buf) + } + + fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result { + self.0.read_vectored(bufs) + } + + #[inline] + fn is_read_vectored(&self) -> bool { + self.0.is_read_vectored() + } +} +#[stable(feature = "rust1", since = "1.0.0")] +impl Write for TcpStream { + fn write(&mut self, buf: &[u8]) -> io::Result { + self.0.write(buf) + } + + fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result { + self.0.write_vectored(bufs) + } + + #[inline] + fn is_write_vectored(&self) -> bool { + self.0.is_write_vectored() + } + + fn flush(&mut self) -> io::Result<()> { + Ok(()) + } +} +#[stable(feature = "rust1", since = "1.0.0")] +impl Read for &TcpStream { + fn read(&mut self, buf: &mut [u8]) -> io::Result { + self.0.read(buf) + } + + fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result { + self.0.read_vectored(bufs) + } + + #[inline] + fn is_read_vectored(&self) -> bool { + self.0.is_read_vectored() + } +} +#[stable(feature = "rust1", since = "1.0.0")] +impl Write for &TcpStream { + fn write(&mut self, buf: &[u8]) -> io::Result { + self.0.write(buf) + } + + fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result { + self.0.write_vectored(bufs) + } + + #[inline] + fn is_write_vectored(&self) -> bool { + self.0.is_write_vectored() + } + + fn flush(&mut self) -> io::Result<()> { + Ok(()) + } +} + +impl AsInner for TcpStream { + fn as_inner(&self) -> &net_imp::TcpStream { + &self.0 + } +} + +impl FromInner for TcpStream { + fn from_inner(inner: net_imp::TcpStream) -> TcpStream { + TcpStream(inner) + } +} + +impl IntoInner for TcpStream { + fn into_inner(self) -> net_imp::TcpStream { + self.0 + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl fmt::Debug for TcpStream { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.0.fmt(f) + } +} + +impl TcpListener { + /// Creates a new `TcpListener` which will be bound to the specified + /// address. + /// + /// The returned listener is ready for accepting connections. + /// + /// Binding with a port number of 0 will request that the OS assigns a port + /// to this listener. The port allocated can be queried via the + /// [`TcpListener::local_addr`] method. + /// + /// The address type can be any implementor of [`ToSocketAddrs`] trait. See + /// its documentation for concrete examples. + /// + /// If `addr` yields multiple addresses, `bind` will be attempted with + /// each of the addresses until one succeeds and returns the listener. If + /// none of the addresses succeed in creating a listener, the error returned + /// from the last attempt (the last address) is returned. + /// + /// # Examples + /// + /// Creates a TCP listener bound to `127.0.0.1:80`: + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// ``` + /// + /// Creates a TCP listener bound to `127.0.0.1:80`. If that fails, create a + /// TCP listener bound to `127.0.0.1:443`: + /// + /// ```no_run + /// use std::net::{SocketAddr, TcpListener}; + /// + /// let addrs = [ + /// SocketAddr::from(([127, 0, 0, 1], 80)), + /// SocketAddr::from(([127, 0, 0, 1], 443)), + /// ]; + /// let listener = TcpListener::bind(&addrs[..]).unwrap(); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn bind(addr: A) -> io::Result { + super::each_addr(addr, net_imp::TcpListener::bind).map(TcpListener) + } + + /// Returns the local socket address of this listener. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::{Ipv4Addr, SocketAddr, SocketAddrV4, TcpListener}; + /// + /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap(); + /// assert_eq!(listener.local_addr().unwrap(), + /// SocketAddr::V4(SocketAddrV4::new(Ipv4Addr::new(127, 0, 0, 1), 8080))); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn local_addr(&self) -> io::Result { + self.0.socket_addr() + } + + /// Creates a new independently owned handle to the underlying socket. + /// + /// The returned [`TcpListener`] is a reference to the same socket that this + /// object references. Both handles can be used to accept incoming + /// connections and options set on one listener will affect the other. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap(); + /// let listener_clone = listener.try_clone().unwrap(); + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn try_clone(&self) -> io::Result { + self.0.duplicate().map(TcpListener) + } + + /// Accept a new incoming connection from this listener. + /// + /// This function will block the calling thread until a new TCP connection + /// is established. When established, the corresponding [`TcpStream`] and the + /// remote peer's address will be returned. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:8080").unwrap(); + /// match listener.accept() { + /// Ok((_socket, addr)) => println!("new client: {addr:?}"), + /// Err(e) => println!("couldn't get client: {e:?}"), + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn accept(&self) -> io::Result<(TcpStream, SocketAddr)> { + // On WASM, `TcpStream` is uninhabited (as it's unsupported) and so + // the `a` variable here is technically unused. + #[cfg_attr(target_arch = "wasm32", allow(unused_variables))] + self.0.accept().map(|(a, b)| (TcpStream(a), b)) + } + + /// Returns an iterator over the connections being received on this + /// listener. + /// + /// The returned iterator will never return [`None`] and will also not yield + /// the peer's [`SocketAddr`] structure. Iterating over it is equivalent to + /// calling [`TcpListener::accept`] in a loop. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::{TcpListener, TcpStream}; + /// + /// fn handle_connection(stream: TcpStream) { + /// //... + /// } + /// + /// fn main() -> std::io::Result<()> { + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// + /// for stream in listener.incoming() { + /// match stream { + /// Ok(stream) => { + /// handle_connection(stream); + /// } + /// Err(e) => { /* connection failed */ } + /// } + /// } + /// Ok(()) + /// } + /// ``` + #[stable(feature = "rust1", since = "1.0.0")] + pub fn incoming(&self) -> Incoming<'_> { + Incoming { listener: self } + } + + /// Turn this into an iterator over the connections being received on this + /// listener. + /// + /// The returned iterator will never return [`None`] and will also not yield + /// the peer's [`SocketAddr`] structure. Iterating over it is equivalent to + /// calling [`TcpListener::accept`] in a loop. + /// + /// # Examples + /// + /// ```no_run + /// #![feature(tcplistener_into_incoming)] + /// use std::net::{TcpListener, TcpStream}; + /// + /// fn listen_on(port: u16) -> impl Iterator { + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// listener.into_incoming() + /// .filter_map(Result::ok) /* Ignore failed connections */ + /// } + /// + /// fn main() -> std::io::Result<()> { + /// for stream in listen_on(80) { + /// /* handle the connection here */ + /// } + /// Ok(()) + /// } + /// ``` + #[must_use = "`self` will be dropped if the result is not used"] + #[unstable(feature = "tcplistener_into_incoming", issue = "88339")] + pub fn into_incoming(self) -> IntoIncoming { + IntoIncoming { listener: self } + } + + /// Sets the value for the `IP_TTL` option on this socket. + /// + /// This value sets the time-to-live field that is used in every packet sent + /// from this socket. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// listener.set_ttl(100).expect("could not set TTL"); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn set_ttl(&self, ttl: u32) -> io::Result<()> { + self.0.set_ttl(ttl) + } + + /// Gets the value of the `IP_TTL` option for this socket. + /// + /// For more information about this option, see [`TcpListener::set_ttl`]. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// listener.set_ttl(100).expect("could not set TTL"); + /// assert_eq!(listener.ttl().unwrap_or(0), 100); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn ttl(&self) -> io::Result { + self.0.ttl() + } + + #[stable(feature = "net2_mutators", since = "1.9.0")] + #[deprecated(since = "1.16.0", note = "this option can only be set before the socket is bound")] + #[allow(missing_docs)] + pub fn set_only_v6(&self, only_v6: bool) -> io::Result<()> { + self.0.set_only_v6(only_v6) + } + + #[stable(feature = "net2_mutators", since = "1.9.0")] + #[deprecated(since = "1.16.0", note = "this option can only be set before the socket is bound")] + #[allow(missing_docs)] + pub fn only_v6(&self) -> io::Result { + self.0.only_v6() + } + + /// Gets the value of the `SO_ERROR` option on this socket. + /// + /// This will retrieve the stored error in the underlying socket, clearing + /// the field in the process. This can be useful for checking errors between + /// calls. + /// + /// # Examples + /// + /// ```no_run + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:80").unwrap(); + /// listener.take_error().expect("No error was expected"); + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn take_error(&self) -> io::Result> { + self.0.take_error() + } + + /// Moves this TCP stream into or out of nonblocking mode. + /// + /// This will result in the `accept` operation becoming nonblocking, + /// i.e., immediately returning from their calls. If the IO operation is + /// successful, `Ok` is returned and no further action is required. If the + /// IO operation could not be completed and needs to be retried, an error + /// with kind [`io::ErrorKind::WouldBlock`] is returned. + /// + /// On Unix platforms, calling this method corresponds to calling `fcntl` + /// `FIONBIO`. On Windows calling this method corresponds to calling + /// `ioctlsocket` `FIONBIO`. + /// + /// # Examples + /// + /// Bind a TCP listener to an address, listen for connections, and read + /// bytes in nonblocking mode: + /// + /// ```no_run + /// use std::io; + /// use std::net::TcpListener; + /// + /// let listener = TcpListener::bind("127.0.0.1:7878").unwrap(); + /// listener.set_nonblocking(true).expect("Cannot set non-blocking"); + /// + /// # fn wait_for_fd() { unimplemented!() } + /// # fn handle_connection(stream: std::net::TcpStream) { unimplemented!() } + /// for stream in listener.incoming() { + /// match stream { + /// Ok(s) => { + /// // do something with the TcpStream + /// handle_connection(s); + /// } + /// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => { + /// // wait until network socket is ready, typically implemented + /// // via platform-specific APIs such as epoll or IOCP + /// wait_for_fd(); + /// continue; + /// } + /// Err(e) => panic!("encountered IO error: {e}"), + /// } + /// } + /// ``` + #[stable(feature = "net2_mutators", since = "1.9.0")] + pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> { + self.0.set_nonblocking(nonblocking) + } +} + +// In addition to the `impl`s here, `TcpListener` also has `impl`s for +// `AsFd`/`From`/`Into` and +// `AsRawFd`/`IntoRawFd`/`FromRawFd`, on Unix and WASI, and +// `AsSocket`/`From`/`Into` and +// `AsRawSocket`/`IntoRawSocket`/`FromRawSocket` on Windows. + +#[stable(feature = "rust1", since = "1.0.0")] +impl<'a> Iterator for Incoming<'a> { + type Item = io::Result; + fn next(&mut self) -> Option> { + Some(self.listener.accept().map(|p| p.0)) + } +} + +#[stable(feature = "tcp_listener_incoming_fused_iterator", since = "1.64.0")] +impl FusedIterator for Incoming<'_> {} + +#[unstable(feature = "tcplistener_into_incoming", issue = "88339")] +impl Iterator for IntoIncoming { + type Item = io::Result; + fn next(&mut self) -> Option> { + Some(self.listener.accept().map(|p| p.0)) + } +} + +#[unstable(feature = "tcplistener_into_incoming", issue = "88339")] +impl FusedIterator for IntoIncoming {} + +impl AsInner for TcpListener { + fn as_inner(&self) -> &net_imp::TcpListener { + &self.0 + } +} + +impl FromInner for TcpListener { + fn from_inner(inner: net_imp::TcpListener) -> TcpListener { + TcpListener(inner) + } +} + +impl IntoInner for TcpListener { + fn into_inner(self) -> net_imp::TcpListener { + self.0 + } +} + +#[stable(feature = "rust1", since = "1.0.0")] +impl fmt::Debug for TcpListener { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + self.0.fmt(f) + } +} -- cgit v1.2.3