[import-netapp] import Netapp code into Garage codebase

src/net/util.rs

@@ -0,0 +1,96 @@
+use std::net::SocketAddr;
+
+use log::info;
+use serde::Serialize;
+
+use tokio::sync::watch;
+
+use crate::netapp::*;
+
+/// Utility function: encodes any serializable value in MessagePack binary format
+/// using the RMP library.
+///
+/// Field names and variant names are included in the serialization.
+/// This is used internally by the netapp communication protocol.
+pub fn rmp_to_vec_all_named<T>(val: &T) -> Result<Vec<u8>, rmp_serde::encode::Error>
+where
+	T: Serialize + ?Sized,
+{
+	let mut wr = Vec::with_capacity(128);
+	let mut se = rmp_serde::Serializer::new(&mut wr).with_struct_map();
+	val.serialize(&mut se)?;
+	Ok(wr)
+}
+
+/// This async function returns only when a true signal was received
+/// from a watcher that tells us when to exit.
+///
+/// Usefull in a select statement to interrupt another
+/// future:
+/// ```ignore
+/// select!(
+///     _ = a_long_task() => Success,
+///     _ = await_exit(must_exit) => Interrupted,
+/// )
+/// ```
+pub async fn await_exit(mut must_exit: watch::Receiver<bool>) {
+	while !*must_exit.borrow_and_update() {
+		if must_exit.changed().await.is_err() {
+			break;
+		}
+	}
+}
+
+/// Creates a watch that contains `false`, and that changes
+/// to `true` when a Ctrl+C signal is received.
+pub fn watch_ctrl_c() -> watch::Receiver<bool> {
+	let (send_cancel, watch_cancel) = watch::channel(false);
+	tokio::spawn(async move {
+		tokio::signal::ctrl_c()
+			.await
+			.expect("failed to install CTRL+C signal handler");
+		info!("Received CTRL+C, shutting down.");
+		send_cancel.send(true).unwrap();
+	});
+	watch_cancel
+}
+
+/// Parse a peer's address including public key, written in the format:
+/// `<public key hex>@<ip>:<port>`
+pub fn parse_peer_addr(peer: &str) -> Option<(NodeID, SocketAddr)> {
+	let delim = peer.find('@')?;
+	let (key, ip) = peer.split_at(delim);
+	let pubkey = NodeID::from_slice(&hex::decode(key).ok()?)?;
+	let ip = ip[1..].parse::<SocketAddr>().ok()?;
+	Some((pubkey, ip))
+}
+
+/// Parse and resolve a peer's address including public key, written in the format:
+/// `<public key hex>@<ip or hostname>:<port>`
+pub fn parse_and_resolve_peer_addr(peer: &str) -> Option<(NodeID, Vec<SocketAddr>)> {
+	use std::net::ToSocketAddrs;
+
+	let delim = peer.find('@')?;
+	let (key, host) = peer.split_at(delim);
+	let pubkey = NodeID::from_slice(&hex::decode(key).ok()?)?;
+	let hosts = host[1..].to_socket_addrs().ok()?.collect::<Vec<_>>();
+	if hosts.is_empty() {
+		return None;
+	}
+	Some((pubkey, hosts))
+}
+
+/// async version of parse_and_resolve_peer_addr
+pub async fn parse_and_resolve_peer_addr_async(peer: &str) -> Option<(NodeID, Vec<SocketAddr>)> {
+	let delim = peer.find('@')?;
+	let (key, host) = peer.split_at(delim);
+	let pubkey = NodeID::from_slice(&hex::decode(key).ok()?)?;
+	let hosts = tokio::net::lookup_host(&host[1..])
+		.await
+		.ok()?
+		.collect::<Vec<_>>();
+	if hosts.is_empty() {
+		return None;
+	}
+	Some((pubkey, hosts))
+}