Struct DualStack 

pub struct DualStack<'set, 'sockets> { /* private fields */ }

A family-aware UdpIo over a v4 and/or v6 smoltcp UDP socket living in a shared SocketSet — the smoltcp transport (single- OR dual-stack), mirroring hick-embassy’s DualUdp.

The engine fans every multicast to BOTH groups, so each datagram must reach the socket of ITS OWN family rather than be enqueued on a mismatched one (which would panic or be silently dropped). try_send routes by the destination’s family and reports SendError::Unsupported for an absent family (the engine then confirms on the family it has); try_recv alternates the two sockets round-robin so a sustained backlog on one family cannot starve the other under the engine’s per-pump RX cap. For a SINGLE-stack node, leave the absent family’s handle None — the family-explicit replacement for naively pumping one raw socket.

pump borrows the SocketSet for the duration of one step; build a fresh DualStack each step (it is a thin view) with DualStack::new, e.g. engine.pump(now, &mut DualStack::new(sockets, Some(h4), Some(h6)), buf).

Implementations

impl<'set, 'sockets> DualStack<'set, 'sockets>

pub fn new( sockets: &'set mut SocketSet<'sockets>, v4: Option<SocketHandle>, v6: Option<SocketHandle>, ) -> Self

Build the transport view for one pump step over a v4 and/or v6 socket living in sockets. Pass None for an absent family on a single-stack node.

Trait Implementations

impl UdpIo for DualStack<'_, '_>

fn try_recv(&mut self, buf: &mut [u8]) -> Option<RecvMeta>

Pull one queued datagram into buf, returning its metadata, or None when the receive queue is empty. Non-blocking.

fn try_send(&mut self, buf: &[u8], dst: SocketAddr) -> Result<(), SendError>

Enqueue one datagram for dst. Non-blocking; returns SendError::Busy when the transmit queue is full, or SendError::Unsupported when there is no socket / route for the datagram’s address family.