Struct UdpSocket 

pub struct UdpSocket { /* private fields */ }

Available on crate feature udp only.

A UDP socket with the guard in front of it.

let mut socket = net_io::UdpSocket::bind("0.0.0.0:5353")?;
let mut buf = [0u8; 1500];
loop {
    let datagram = socket.recv_from(&mut buf)?;
    if datagram.truncated {
        continue; // larger than we accept
    }
    // Replies are limited to the size of what the peer sent until it is verified.
    socket.send_to(&buf[..datagram.len], datagram.from)?;
}

Implementations

impl UdpSocket

pub fn bind<A: ToSocketAddrs>(addr: A) -> Result<UdpSocket, NetError>

Binds with UdpOptions::new. The first resolved address that binds wins.

Errors

AddrInUse, AddrNotAvailable, PermissionDenied, NoAddresses, Bind.

pub fn bind_with<A: ToSocketAddrs>( addr: A, options: UdpOptions, ) -> Result<UdpSocket, NetError>

Binds with options.

Errors

As UdpSocket::bind; InvalidConfig for an option out of range.

pub fn recv_from(&mut self, buf: &mut [u8]) -> Result<Datagram, NetError>

Receives one datagram within the budgets. Datagrams over budget are read, dropped, and counted; ICMP error reports are counted and never end the socket. Under a flood the call returns within twice the read timeout.

Errors

TimedOut { kind: Read } (only with a read timeout), Os.

pub fn recv_batch( &mut self, slots: &mut [DatagramBuffer<'_>], ) -> Result<usize, NetError>

Waits for a datagram, then takes what else is ready, up to slots.len() (64 at most). Each datagram passes the budgets as in UdpSocket::recv_from: one that does not leaves its slot’s datagram at None, so walk every slot. One system call on Linux (recvmmsg), a loop elsewhere. Returns how many slots hold a datagram. Packet info is not reported here.

Errors

As UdpSocket::recv_from.

pub fn send_batch( &mut self, datagrams: &[OutgoingDatagram<'_>], ) -> Result<usize, NetError>

Sends from the front of datagrams, each under the guard of UdpSocket::send_to, until one is refused or the OS takes no more. One system call per 64 on Linux (sendmmsg), a loop elsewhere. Returns how many went.

Errors

Limit { which: Amplification } when the first is refused, Os.

pub fn join_multicast( &self, group: IpAddr, interface: MulticastInterface, ) -> Result<(), NetError>

Joins a multicast group. Datagrams to the group then pass the same budgets as any other; a reply to a group member is still under the amplification guard.

Errors

InvalidConfig when the interface’s family is not the group’s, Os.

pub fn recv(&mut self, buf: &mut [u8]) -> Result<Datagram, NetError>

Receives from the connected peer (see UdpSocket::connect).

Errors

As UdpSocket::recv_from.

pub fn send_to(&mut self, buf: &[u8], to: SocketAddr) -> Result<usize, NetError>

Sends one datagram. To a source not marked verified, the bytes sent within the window never exceed factor times the bytes received from it; a source never heard from gets nothing (an empty datagram aside).

Errors

Limit { which: Amplification } (nothing was sent), Os.

pub fn send(&mut self, buf: &[u8]) -> Result<usize, NetError>

Sends to the connected peer, under the same guard as UdpSocket::send_to.

Errors

Closed when not connected; as UdpSocket::send_to.

pub fn connect(&mut self, to: SocketAddr) -> Result<(), NetError>

Fixes the peer: the kernel drops datagrams from other sources, and UdpSocket::send goes to it.

Errors

Os.

pub fn mark_verified(&mut self, peer: SocketAddr)

The protocol proved peer can receive (a cookie, a handshake): the guard no longer limits sends to it, and its table entry is kept.

pub fn set_read_timeout( &mut self, timeout: Option<Duration>, ) -> Result<(), NetError>

How long a receive waits (None: forever, the default).

Errors

InvalidConfig for a zero duration, Os.

pub fn local_addr(&self) -> Result<SocketAddr, NetError>

The bound address.

Errors

Os when getsockname fails.

pub fn stats(&self) -> UdpStats

Counters since the socket was bound.

Trait Implementations

impl AsFd for UdpSocket

Available on Unix only.

fn as_fd(&self) -> BorrowedFd<'_>

Borrows the file descriptor.

impl Debug for UdpSocket

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.