fluencelabs/rust-libp2p
1
0
Fork 0
mirror of https://github.com/fluencelabs/rust-libp2p synced 2025-04-25 11:02:12 +00:00
Code Issues Projects Releases Wiki Activity

Adds support for handling interface changes to mdns behaviour. (#1830)

Browse Source 
* mdns: handle address changes.

* Update examples.

* Use async-io.

* Fix tokio-chat.

* Address review comments.

* Update if-watch.

* Poll interfaces correctly.

* Use socket2 and remove wasm-time.

* Update if-watch.

* Update versions and changelogs.

* Further changelog updates.

Co-authored-by: Roman Borschel <romanb@users.noreply.github.com>
Co-authored-by: Roman S. Borschel <roman@parity.io>
This commit is contained in:
David Craven 2020-12-03 13:30:52 +01:00 committed by GitHub
parent 4bdb61be0d
commit 505a17dfc2
No known key found for this signature in database
GPG Key ID: 4AEE18F83AFDEB23
13 changed files with 161 additions and 167 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
CHANGELOG.md
View File

@ -23,6 +23,10 @@
- [`parity-multiaddr` CHANGELOG](misc/multiaddr/CHANGELOG.md)
- [`libp2p-core-derive` CHANGELOG](misc/core-derive/CHANGELOG.md)
# Version 0.32.0 [unreleased]
- Update to `libp2p-mdns-0.26`.
# Version 0.31.2 [2020-12-02]
- Bump minimum `libp2p-core` patch version.

11
Cargo.toml
View File

@ -2,7 +2,7 @@
name = "libp2p"
edition = "2018"
description = "Peer-to-peer networking library"
version = "0.31.2"
version = "0.32.0"
authors = ["Parity Technologies <admin@parity.io>"]
license = "MIT"
repository = "https://github.com/libp2p/rust-libp2p"
@ -17,7 +17,7 @@ default = [
"identify",
"kad",
"gossipsub",
"mdns-async-std",
"mdns",
"mplex",
"noise",
"ping",
@ -37,8 +37,7 @@ floodsub = ["libp2p-floodsub"]
identify = ["libp2p-identify"]
kad = ["libp2p-kad"]
gossipsub = ["libp2p-gossipsub"]
mdns-async-std = ["libp2p-mdns", "libp2p-mdns/async-std"]
mdns-tokio = ["libp2p-mdns", "libp2p-mdns/tokio"]
mdns = ["libp2p-mdns"]
mplex = ["libp2p-mplex"]
noise = ["libp2p-noise"]
ping = ["libp2p-ping"]
@ -87,7 +86,7 @@ wasm-timer = "0.2.4"
[target.'cfg(not(any(target_os = "emscripten", target_os = "wasi", target_os = "unknown")))'.dependencies]
libp2p-deflate = { version = "0.25.0", path = "protocols/deflate", optional = true }
libp2p-dns = { version = "0.25.0", path = "transports/dns", optional = true }
libp2p-mdns = { version = "0.25.0", path = "protocols/mdns", optional = true }
libp2p-mdns = { version = "0.26.0", path = "protocols/mdns", optional = true }
libp2p-tcp = { version = "0.25.1", path = "transports/tcp", optional = true }
libp2p-websocket = { version = "0.26.0", path = "transports/websocket", optional = true }
@ -125,4 +124,4 @@ members = [
[[example]]
name = "chat-tokio"
required-features = ["tcp-tokio", "mdns-tokio"]
required-features = ["tcp-tokio", "mdns"]

9
examples/chat-tokio.rs
View File

@ -46,8 +46,7 @@ use libp2p::{
core::upgrade,
identity,
floodsub::{self, Floodsub, FloodsubEvent},
// `TokioMdns` is available through the `mdns-tokio` feature.
mdns::{TokioMdns, MdnsEvent},
mdns::{Mdns, MdnsEvent},
mplex,
noise,
swarm::{NetworkBehaviourEventProcess, SwarmBuilder},
@ -90,7 +89,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
#[derive(NetworkBehaviour)]
struct MyBehaviour {
floodsub: Floodsub,
mdns: TokioMdns,
mdns: Mdns,
}
impl NetworkBehaviourEventProcess<FloodsubEvent> for MyBehaviour {
@ -122,7 +121,7 @@ async fn main() -> Result<(), Box<dyn Error>> {
// Create a Swarm to manage peers and events.
let mut swarm = {
let mdns = TokioMdns::new()?;
let mdns = Mdns::new().await?;
let mut behaviour = MyBehaviour {
floodsub: Floodsub::new(peer_id.clone()),
mdns,
@ -172,4 +171,4 @@ async fn main() -> Result<(), Box<dyn Error>> {
}
}
}
}
}

2
examples/chat.rs
View File

@ -121,7 +121,7 @@ fn main() -> Result<(), Box<dyn Error>> {
// Create a Swarm to manage peers and events
let mut swarm = {
let mdns = Mdns::new()?;
let mdns = task::block_on(Mdns::new())?;
let mut behaviour = MyBehaviour {
floodsub: Floodsub::new(local_peer_id.clone()),
mdns,

2
examples/distributed-key-value-store.rs
View File

@ -151,7 +151,7 @@ fn main() -> Result<(), Box<dyn Error>> {
// Create a Kademlia behaviour.
let store = MemoryStore::new(local_peer_id.clone());
let kademlia = Kademlia::new(local_peer_id.clone(), store);
let mdns = Mdns::new()?;
let mdns = task::block_on(Mdns::new())?;
let behaviour = MyBehaviour { kademlia, mdns };
Swarm::new(transport, behaviour, local_peer_id)
};

2
examples/mdns-passive-discovery.rs
View File

@ -26,7 +26,7 @@ fn main() -> Result<(), Box<dyn Error>> {
// This example provides passive discovery of the libp2p nodes on the
// network that send mDNS queries and answers.
task::block_on(async move {
let mut service = MdnsService::new()?;
let mut service = MdnsService::new().await?;
loop {
let (srv, packet) = service.next().await;
match packet {

13
protocols/mdns/CHANGELOG.md
View File

@ -1,3 +1,16 @@
# 0.26.0 [unreleased]
- Detect interface changes and join the MDNS multicast
group on all interfaces as they become available.
[PR 1830](https://github.com/libp2p/rust-libp2p/pull/1830).
- Replace the use of macros for abstracting over `tokio`
and `async-std` with the use of `async-io`. As a result
there may now be an additional reactor thread running
called `async-io` when using `tokio`, with the futures
still being polled by the `tokio` runtime.
[PR 1830](https://github.com/libp2p/rust-libp2p/pull/1830).
# 0.25.0 [2020-11-25]
- Update `libp2p-swarm` and `libp2p-core`.

31
protocols/mdns/Cargo.toml
View File

@ -1,7 +1,7 @@
[package]
name = "libp2p-mdns"
edition = "2018"
version = "0.25.0"
version = "0.26.0"
description = "Implementation of the libp2p mDNS discovery method"
authors = ["Parity Technologies <admin@parity.io>"]
license = "MIT"
@ -10,22 +10,21 @@ keywords = ["peer-to-peer", "libp2p", "networking"]
categories = ["network-programming", "asynchronous"]
[dependencies]
async-std = { version = "1.6.2", optional = true }
data-encoding = "2.0"
dns-parser = "0.8"
either = "1.5.3"
futures = "0.3.1"
lazy_static = "1.2"
async-io = "1.3.0"
data-encoding = "2.3.1"
dns-parser = "0.8.0"
futures = "0.3.8"
if-watch = "0.1.6"
lazy_static = "1.4.0"
libp2p-core = { version = "0.25.0", path = "../../core" }
libp2p-swarm = { version = "0.25.0", path = "../../swarm" }
log = "0.4"
net2 = "0.2"
rand = "0.7"
smallvec = "1.0"
tokio = { version = "0.3", default-features = false, features = ["net"], optional = true }
void = "1.0"
wasm-timer = "0.2.4"
log = "0.4.11"
rand = "0.7.3"
smallvec = "1.5.0"
socket2 = { version = "0.3.17", features = ["reuseport"] }
void = "1.0.2"
[dev-dependencies]
if-addrs = "0.6.4"
tokio = { version = "0.3", default-features = false, features = ["rt", "rt-multi-thread"] }
async-std = "1.7.0"
if-addrs = "0.6.5"
tokio = { version = "0.3.4", default-features = false, features = ["rt", "rt-multi-thread"] }

87
protocols/mdns/src/behaviour.rs
View File

@ -18,7 +18,8 @@
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
use crate::service::{MdnsPacket, build_query_response, build_service_discovery_response};
use crate::service::{MdnsPacket, MdnsService, build_query_response, build_service_discovery_response};
use async_io::Timer;
use futures::prelude::*;
use libp2p_core::{
Multiaddr,
@ -34,21 +35,16 @@ use libp2p_swarm::{
ProtocolsHandler,
protocols_handler::DummyProtocolsHandler
};
use log::warn;
use smallvec::SmallVec;
use std::{cmp, fmt, io, iter, mem, pin::Pin, time::Duration, task::Context, task::Poll};
use wasm_timer::{Delay, Instant};
use std::{cmp, fmt, io, iter, mem, pin::Pin, time::{Duration, Instant}, task::Context, task::Poll};
const MDNS_RESPONSE_TTL: std::time::Duration = Duration::from_secs(5 * 60);
macro_rules! codegen {
($feature_name:expr, $behaviour_name:ident, $maybe_busy_wrapper:ident, $service_name:ty) => {
/// A `NetworkBehaviour` for mDNS. Automatically discovers peers on the local network and adds
/// them to the topology.
pub struct $behaviour_name {
pub struct Mdns {
/// The inner service.
service: $maybe_busy_wrapper,
service: MdnsBusyWrapper,
/// List of nodes that we have discovered, the address, and when their TTL expires.
///
@ -59,44 +55,44 @@ pub struct $behaviour_name {
/// Future that fires when the TTL of at least one node in `discovered_nodes` expires.
///
/// `None` if `discovered_nodes` is empty.
closest_expiration: Option<Delay>,
closest_expiration: Option<Timer>,
}
/// `MdnsService::next` takes ownership of `self`, returning a future that resolves with both itself
/// and a `MdnsPacket` (similar to the old Tokio socket send style). The two states are thus `Free`
/// with an `MdnsService` or `Busy` with a future returning the original `MdnsService` and an
/// `MdnsPacket`.
enum $maybe_busy_wrapper {
Free($service_name),
Busy(Pin<Box<dyn Future<Output = ($service_name, MdnsPacket)> + Send>>),
enum MdnsBusyWrapper {
Free(MdnsService),
Busy(Pin<Box<dyn Future<Output = (MdnsService, MdnsPacket)> + Send>>),
Poisoned,
}
impl fmt::Debug for $maybe_busy_wrapper {
impl fmt::Debug for MdnsBusyWrapper {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
match self {
$maybe_busy_wrapper::Free(service) => {
fmt.debug_struct("$maybe_busy_wrapper::Free")
Self::Free(service) => {
fmt.debug_struct("MdnsBusyWrapper::Free")
.field("service", service)
.finish()
},
$maybe_busy_wrapper::Busy(_) => {
fmt.debug_struct("$maybe_busy_wrapper::Busy")
Self::Busy(_) => {
fmt.debug_struct("MdnsBusyWrapper::Busy")
.finish()
}
$maybe_busy_wrapper::Poisoned => {
fmt.debug_struct("$maybe_busy_wrapper::Poisoned")
Self::Poisoned => {
fmt.debug_struct("MdnsBusyWrapper::Poisoned")
.finish()
}
}
}
}
impl $behaviour_name {
impl Mdns {
/// Builds a new `Mdns` behaviour.
pub fn new() -> io::Result<$behaviour_name> {
Ok($behaviour_name {
service: $maybe_busy_wrapper::Free(<$service_name>::new()?),
pub async fn new() -> io::Result<Self> {
Ok(Self {
service: MdnsBusyWrapper::Free(MdnsService::new().await?),
discovered_nodes: SmallVec::new(),
closest_expiration: None,
})
@ -113,7 +109,7 @@ impl $behaviour_name {
}
}
impl NetworkBehaviour for $behaviour_name {
impl NetworkBehaviour for Mdns {
type ProtocolsHandler = DummyProtocolsHandler;
type OutEvent = MdnsEvent;
@ -138,9 +134,9 @@ impl NetworkBehaviour for $behaviour_name {
&mut self,
_: PeerId,
_: ConnectionId,
_ev: <Self::ProtocolsHandler as ProtocolsHandler>::OutEvent,
ev: <Self::ProtocolsHandler as ProtocolsHandler>::OutEvent,
) {
void::unreachable(_ev)
void::unreachable(ev)
}
fn poll(
@ -155,9 +151,8 @@ impl NetworkBehaviour for $behaviour_name {
> {
// Remove expired peers.
if let Some(ref mut closest_expiration) = self.closest_expiration {
match Future::poll(Pin::new(closest_expiration), cx) {
Poll::Ready(Ok(())) => {
let now = Instant::now();
match Pin::new(closest_expiration).poll(cx) {
Poll::Ready(now) => {
let mut expired = SmallVec::<[(PeerId, Multiaddr); 4]>::new();
while let Some(pos) = self.discovered_nodes.iter().position(|(_, _, exp)| *exp < now) {
let (peer_id, addr, _) = self.discovered_nodes.remove(pos);
@ -173,38 +168,37 @@ impl NetworkBehaviour for $behaviour_name {
}
},
Poll::Pending => (),
Poll::Ready(Err(err)) => warn!("timer has errored: {:?}", err),
}
}
// Polling the mDNS service, and obtain the list of nodes discovered this round.
let discovered = loop {
let service = mem::replace(&mut self.service, $maybe_busy_wrapper::Poisoned);
let service = mem::replace(&mut self.service, MdnsBusyWrapper::Poisoned);
let packet = match service {
$maybe_busy_wrapper::Free(service) => {
self.service = $maybe_busy_wrapper::Busy(Box::pin(service.next()));
MdnsBusyWrapper::Free(service) => {
self.service = MdnsBusyWrapper::Busy(Box::pin(service.next()));
continue;
},
$maybe_busy_wrapper::Busy(mut fut) => {
MdnsBusyWrapper::Busy(mut fut) => {
match fut.as_mut().poll(cx) {
Poll::Ready((service, packet)) => {
self.service = $maybe_busy_wrapper::Free(service);
self.service = MdnsBusyWrapper::Free(service);
packet
},
Poll::Pending => {
self.service = $maybe_busy_wrapper::Busy(fut);
self.service = MdnsBusyWrapper::Busy(fut);
return Poll::Pending;
}
}
},
$maybe_busy_wrapper::Poisoned => panic!("Mdns poisoned"),
MdnsBusyWrapper::Poisoned => panic!("Mdns poisoned"),
};
match packet {
MdnsPacket::Query(query) => {
// MaybeBusyMdnsService should always be Free.
if let $maybe_busy_wrapper::Free(ref mut service) = self.service {
if let MdnsBusyWrapper::Free(ref mut service) = self.service {
let resp = build_query_response(
query.query_id(),
params.local_peer_id().clone(),
@ -256,7 +250,7 @@ impl NetworkBehaviour for $behaviour_name {
},
MdnsPacket::ServiceDiscovery(disc) => {
// MaybeBusyMdnsService should always be Free.
if let $maybe_busy_wrapper::Free(ref mut service) = self.service {
if let MdnsBusyWrapper::Free(ref mut service) = self.service {
let resp = build_service_discovery_response(
disc.query_id(),
MDNS_RESPONSE_TTL,
@ -273,7 +267,7 @@ impl NetworkBehaviour for $behaviour_name {
.fold(None, |exp, &(_, _, elem_exp)| {
Some(exp.map(|exp| cmp::min(exp, elem_exp)).unwrap_or(elem_exp))
})
.map(Delay::new_at);
.map(Timer::at);
Poll::Ready(NetworkBehaviourAction::GenerateEvent(MdnsEvent::Discovered(DiscoveredAddrsIter {
inner: discovered.into_iter(),
@ -281,7 +275,7 @@ impl NetworkBehaviour for $behaviour_name {
}
}
impl fmt::Debug for $behaviour_name {
impl fmt::Debug for Mdns {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_struct("Mdns")
.field("service", &self.service)
@ -289,15 +283,6 @@ impl fmt::Debug for $behaviour_name {
}
}
};
}
#[cfg(feature = "async-std")]
codegen!("async-std", Mdns, MaybeBusyMdnsService, crate::service::MdnsService);
#[cfg(feature = "tokio")]
codegen!("tokio", TokioMdns, MaybeBusyTokioMdnsService, crate::service::TokioMdnsService);
/// Event that can be produced by the `Mdns` behaviour.
#[derive(Debug)]
pub enum MdnsEvent {

4
protocols/mdns/src/dns.rs
View File

@ -22,9 +22,7 @@
//! `dns_parser` library.
use crate::{META_QUERY_SERVICE, SERVICE_NAME};
use data_encoding;
use libp2p_core::{Multiaddr, PeerId};
use rand;
use std::{borrow::Cow, cmp, error, fmt, str, time::Duration};
/// Maximum size of a DNS label as per RFC1035
@ -226,7 +224,7 @@ fn segment_peer_id(peer_id: String) -> String {
/// Combines and encodes a `PeerId` and service name for a DNS query.
fn encode_peer_id(peer_id: &PeerId) -> Vec<u8> {
// DNS-safe encoding for the Peer ID
// DNS-safe encoding for the Peer ID
let raw_peer_id = data_encoding::BASE32_DNSCURVE.encode(&peer_id.as_bytes());
// ensure we don't have any labels over 63 bytes long
let encoded_peer_id = segment_peer_id(raw_peer_id);

10
protocols/mdns/src/lib.rs
View File

@ -35,12 +35,10 @@ const SERVICE_NAME: &[u8] = b"_p2p._udp.local";
/// Hardcoded name of the service used for DNS-SD.
const META_QUERY_SERVICE: &[u8] = b"_services._dns-sd._udp.local";
#[cfg(feature = "async-std")]
pub use self::{behaviour::Mdns, service::MdnsService};
#[cfg(feature = "tokio")]
pub use self::{behaviour::TokioMdns, service::TokioMdnsService};
pub use self::behaviour::MdnsEvent;
pub use crate::{
behaviour::{Mdns, MdnsEvent},
service::MdnsService,
};
mod behaviour;
mod dns;

149
protocols/mdns/src/service.rs
View File

@ -19,14 +19,15 @@
// DEALINGS IN THE SOFTWARE.
use crate::{SERVICE_NAME, META_QUERY_SERVICE, dns};
use async_io::{Async, Timer};
use dns_parser::{Packet, RData};
use either::Either::{Left, Right};
use futures::{future, prelude::*};
use futures::{prelude::*, select};
use if_watch::{IfEvent, IfWatcher};
use lazy_static::lazy_static;
use libp2p_core::{multiaddr::{Multiaddr, Protocol}, PeerId};
use log::warn;
use std::{convert::TryFrom as _, fmt, io, net::Ipv4Addr, net::SocketAddr, str, time::{Duration, Instant}};
use wasm_timer::Interval;
use lazy_static::lazy_static;
use socket2::{Socket, Domain, Type};
use std::{convert::TryFrom, fmt, io, net::{IpAddr, Ipv4Addr, UdpSocket, SocketAddr}, str, time::{Duration, Instant}};
pub use dns::{MdnsResponseError, build_query_response, build_service_discovery_response};
@ -37,9 +38,6 @@ lazy_static! {
));
}
macro_rules! codegen {
($feature_name:expr, $service_name:ident, $udp_socket:ty, $udp_socket_from_std:tt) => {
/// A running service that discovers libp2p peers and responds to other libp2p peers' queries on
/// the local network.
///
@ -71,10 +69,7 @@ macro_rules! codegen {
/// # let my_peer_id = PeerId::from(identity::Keypair::generate_ed25519().public());
/// # let my_listened_addrs: Vec<Multiaddr> = vec![];
/// # async {
/// # #[cfg(feature = "async-std")]
/// # let mut service = libp2p_mdns::service::MdnsService::new().unwrap();
/// # #[cfg(feature = "tokio")]
/// # let mut service = libp2p_mdns::service::TokioMdnsService::new().unwrap();
/// # let mut service = libp2p_mdns::service::MdnsService::new().await.unwrap();
/// let _future_to_poll = async {
/// let (mut service, packet) = service.next().await;
///
@ -108,19 +103,18 @@ macro_rules! codegen {
/// };
/// # };
/// # }
#[cfg_attr(docsrs, doc(cfg(feature = $feature_name)))]
pub struct $service_name {
pub struct MdnsService {
/// Main socket for listening.
socket: $udp_socket,
socket: Async<UdpSocket>,
/// Socket for sending queries on the network.
query_socket: $udp_socket,
query_socket: Async<UdpSocket>,
/// Interval for sending queries.
query_interval: Interval,
query_interval: Timer,
/// Whether we send queries on the network at all.
/// Note that we still need to have an interval for querying, as we need to wake up the socket
/// regularly to recover from errors. Otherwise we could simply use an `Option<Interval>`.
/// regularly to recover from errors. Otherwise we could simply use an `Option<Timer>`.
silent: bool,
/// Buffer used for receiving data from the main socket.
/// RFC6762 discourages packets larger than the interface MTU, but allows sizes of up to 9000
@ -133,55 +127,54 @@ pub struct $service_name {
send_buffers: Vec<Vec<u8>>,
/// Buffers pending to send on the query socket.
query_send_buffers: Vec<Vec<u8>>,
/// Iface watch.
if_watch: IfWatcher,
}
impl $service_name {
impl MdnsService {
/// Starts a new mDNS service.
pub fn new() -> io::Result<$service_name> {
Self::new_inner(false)
pub async fn new() -> io::Result<Self> {
Self::new_inner(false).await
}
/// Same as `new`, but we don't automatically send queries on the network.
pub fn silent() -> io::Result<$service_name> {
Self::new_inner(true)
pub async fn silent() -> io::Result<Self> {
Self::new_inner(true).await
}
/// Starts a new mDNS service.
fn new_inner(silent: bool) -> io::Result<$service_name> {
let std_socket = {
async fn new_inner(silent: bool) -> io::Result<Self> {
let socket = {
let socket = Socket::new(Domain::ipv4(), Type::dgram(), Some(socket2::Protocol::udp()))?;
socket.set_reuse_address(true)?;
#[cfg(unix)]
fn platform_specific(s: &net2::UdpBuilder) -> io::Result<()> {
net2::unix::UnixUdpBuilderExt::reuse_port(s, true)?;
Ok(())
}
#[cfg(not(unix))]
fn platform_specific(_: &net2::UdpBuilder) -> io::Result<()> { Ok(()) }
let builder = net2::UdpBuilder::new_v4()?;
builder.reuse_address(true)?;
platform_specific(&builder)?;
builder.bind(("0.0.0.0", 5353))?
socket.set_reuse_port(true)?;
socket.bind(&SocketAddr::new(Ipv4Addr::UNSPECIFIED.into(), 5353).into())?;
let socket = socket.into_udp_socket();
socket.set_multicast_loop_v4(true)?;
socket.set_multicast_ttl_v4(255)?;
Async::new(socket)?
};
let socket = $udp_socket_from_std(std_socket)?;
// Given that we pass an IP address to bind, which does not need to be resolved, we can
// use std::net::UdpSocket::bind, instead of its async counterpart from async-std.
let query_socket = $udp_socket_from_std(
std::net::UdpSocket::bind((Ipv4Addr::from([0u8, 0, 0, 0]), 0u16))?,
)?;
let query_socket = {
let socket = std::net::UdpSocket::bind((Ipv4Addr::UNSPECIFIED, 0))?;
Async::new(socket)?
};
socket.set_multicast_loop_v4(true)?;
socket.set_multicast_ttl_v4(255)?;
// TODO: correct interfaces?
socket.join_multicast_v4(From::from([224, 0, 0, 251]), Ipv4Addr::UNSPECIFIED)?;
Ok($service_name {
let if_watch = if_watch::IfWatcher::new().await?;
Ok(Self {
socket,
query_socket,
query_interval: Interval::new_at(Instant::now(), Duration::from_secs(20)),
query_interval: Timer::interval_at(Instant::now(), Duration::from_secs(20)),
silent,
recv_buffer: [0; 4096],
send_buffers: Vec::new(),
query_send_buffers: Vec::new(),
if_watch,
})
}
@ -247,18 +240,8 @@ impl $service_name {
}
}
// Either (left) listen for incoming packets or (right) send query packets whenever the
// query interval fires.
let selected_output = match futures::future::select(
Box::pin(self.socket.recv_from(&mut self.recv_buffer)),
Box::pin(self.query_interval.next()),
).await {
future::Either::Left((recved, _)) => Left(recved),
future::Either::Right(_) => Right(()),
};
match selected_output {
Left(left) => match left {
select! {
res = self.socket.recv_from(&mut self.recv_buffer).fuse() => match res {
Ok((len, from)) => {
match MdnsPacket::new_from_bytes(&self.recv_buffer[..len], from) {
Some(packet) => return (self, packet),
@ -270,7 +253,7 @@ impl $service_name {
// The query interval will wake up the task at some point so that we can try again.
},
},
Right(_) => {
_ = self.query_interval.next().fuse() => {
// Ensure underlying task is woken up on the next interval tick.
while let Some(_) = self.query_interval.next().now_or_never() {};
@ -278,13 +261,42 @@ impl $service_name {
let query = dns::build_query();
self.query_send_buffers.push(query.to_vec());
}
},
event = self.if_watch.next().fuse() => {
let multicast = From::from([224, 0, 0, 251]);
let socket = self.socket.get_ref();
match event {
Ok(IfEvent::Up(inet)) => {
if inet.addr().is_loopback() {
continue;
}
if let IpAddr::V4(addr) = inet.addr() {
log::trace!("joining multicast on iface {}", addr);
if let Err(err) = socket.join_multicast_v4(&multicast, &addr) {
log::error!("join multicast failed: {}", err);
}
}
}
Ok(IfEvent::Down(inet)) => {
if inet.addr().is_loopback() {
continue;
}
if let IpAddr::V4(addr) = inet.addr() {
log::trace!("leaving multicast on iface {}", addr);
if let Err(err) = socket.leave_multicast_v4(&multicast, &addr) {
log::error!("leave multicast failed: {}", err);
}
}
}
Err(err) => log::error!("if watch returned an error: {}", err),
}
}
};
}
}
}
impl fmt::Debug for $service_name {
impl fmt::Debug for MdnsService {
fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
fmt.debug_struct("$service_name")
.field("silent", &self.silent)
@ -292,17 +304,6 @@ impl fmt::Debug for $service_name {
}
}
};
}
#[cfg(feature = "async-std")]
codegen!("async-std", MdnsService, async_std::net::UdpSocket, (|socket| Ok::<_, std::io::Error>(async_std::net::UdpSocket::from(socket))));
// Note: Tokio's UdpSocket::from_std does not set the socket into non-blocking mode.
#[cfg(feature = "tokio")]
codegen!("tokio", TokioMdnsService, tokio::net::UdpSocket, (|socket: std::net::UdpSocket| { socket.set_nonblocking(true); tokio::net::UdpSocket::from_std(socket) }));
/// A valid mDNS packet received by the service.
#[derive(Debug)]
pub enum MdnsPacket {
@ -595,7 +596,7 @@ mod tests {
fn discover(peer_id: PeerId) {
let fut = async {
let mut service = <$service_name>::new().unwrap();
let mut service = <$service_name>::new().await.unwrap();
loop {
let next = service.next().await;
@ -639,7 +640,7 @@ mod tests {
.collect();
let fut = async {
let mut service = <$service_name>::new().unwrap();
let mut service = <$service_name>::new().await.unwrap();
let mut sent_queries = vec![];
@ -690,17 +691,15 @@ mod tests {
}
}
#[cfg(feature = "async-std")]
testgen!(
async_std,
crate::service::MdnsService,
(|fut| async_std::task::block_on::<_, ()>(fut))
);
#[cfg(feature = "tokio")]
testgen!(
tokio,
crate::service::TokioMdnsService,
crate::service::MdnsService,
(|fut| tokio::runtime::Runtime::new().unwrap().block_on::<futures::future::BoxFuture<()>>(fut))
);
}

4
src/lib.rs
View File

@ -196,8 +196,8 @@ pub use libp2p_gossipsub as gossipsub;
#[cfg_attr(docsrs, doc(cfg(feature = "mplex")))]
#[doc(inline)]
pub use libp2p_mplex as mplex;
#[cfg(any(feature = "mdns-async-std", feature = "mdns-tokio"))]
#[cfg_attr(docsrs, doc(cfg(any(feature = "mdns-async-std", feature = "mdns-tokio"))))]
#[cfg(feature = "mdns")]
#[cfg_attr(docsrs, doc(cfg(feature = "mdns")))]
#[cfg(not(any(target_os = "emscripten", target_os = "wasi", target_os = "unknown")))]
#[doc(inline)]
pub use libp2p_mdns as mdns;