Add UDP example app

examples/std/Cargo.toml

@@ -6,7 +6,7 @@ version = "0.1.0"
 [dependencies]
 embassy-util = { version = "0.1.0", path = "../../embassy-util", features = ["log"] }
 embassy-executor = { version = "0.1.0", path = "../../embassy-executor", features = ["log", "std", "time", "nightly"] }
-embassy-net = { version = "0.1.0", path = "../../embassy-net", features=[ "std", "log", "medium-ethernet", "tcp", "dhcpv4", "pool-16"] }
+embassy-net = { version = "0.1.0", path = "../../embassy-net", features=[ "std", "log", "medium-ethernet", "tcp", "udp", "dhcpv4", "pool-16"] }
 embedded-io = { version = "0.3.0", features = ["async", "std", "futures"] }
 
 async-io = "1.6.0"

examples/std/src/bin/net_udp.rs

@@ -0,0 +1,109 @@
+#![feature(type_alias_impl_trait)]
+
+use clap::Parser;
+use embassy_executor::executor::{Executor, Spawner};
+use embassy_net::udp::UdpSocket;
+use embassy_net::{ConfigStrategy, Ipv4Address, Ipv4Cidr, PacketMetadata, Stack, StackResources};
+use embassy_util::Forever;
+use heapless::Vec;
+use log::*;
+use rand_core::{OsRng, RngCore};
+
+#[path = "../tuntap.rs"]
+mod tuntap;
+
+use crate::tuntap::TunTapDevice;
+
+macro_rules! forever {
+    ($val:expr) => {{
+        type T = impl Sized;
+        static FOREVER: Forever<T> = Forever::new();
+        FOREVER.put_with(move || $val)
+    }};
+}
+
+#[derive(Parser)]
+#[clap(version = "1.0")]
+struct Opts {
+    /// TAP device name
+    #[clap(long, default_value = "tap0")]
+    tap: String,
+    /// use a static IP instead of DHCP
+    #[clap(long)]
+    static_ip: bool,
+}
+
+#[embassy_executor::task]
+async fn net_task(stack: &'static Stack<TunTapDevice>) -> ! {
+    stack.run().await
+}
+
+#[embassy_executor::task]
+async fn main_task(spawner: Spawner) {
+    let opts: Opts = Opts::parse();
+
+    // Init network device
+    let device = TunTapDevice::new(&opts.tap).unwrap();
+
+    // Choose between dhcp or static ip
+    let config = if opts.static_ip {
+        ConfigStrategy::Static(embassy_net::Config {
+            address: Ipv4Cidr::new(Ipv4Address::new(192, 168, 69, 2), 24),
+            dns_servers: Vec::new(),
+            gateway: Some(Ipv4Address::new(192, 168, 69, 1)),
+        })
+    } else {
+        ConfigStrategy::Dhcp
+    };
+
+    // Generate random seed
+    let mut seed = [0; 8];
+    OsRng.fill_bytes(&mut seed);
+    let seed = u64::from_le_bytes(seed);
+
+    // Init network stack
+    let stack = &*forever!(Stack::new(
+        device,
+        config,
+        forever!(StackResources::<1, 2, 8>::new()),
+        seed
+    ));
+
+    // Launch network task
+    spawner.spawn(net_task(stack)).unwrap();
+
+    // Then we can use it!
+    let mut rx_meta = [PacketMetadata::EMPTY; 16];
+    let mut rx_buffer = [0; 4096];
+    let mut tx_meta = [PacketMetadata::EMPTY; 16];
+    let mut tx_buffer = [0; 4096];
+    let mut buf = [0; 4096];
+
+    let mut socket = UdpSocket::new(stack, &mut rx_meta, &mut rx_buffer, &mut tx_meta, &mut tx_buffer);
+    socket.bind(9400).unwrap();
+
+    loop {
+        let (n, ep) = socket.recv_from(&mut buf).await.unwrap();
+        if let Ok(s) = core::str::from_utf8(&buf[..n]) {
+            info!("ECHO (to {}): {}", ep, s);
+        } else {
+            info!("ECHO (to {}): bytearray len {}", ep, n);
+        }
+        socket.send_to(&buf[..n], ep).await.unwrap();
+    }
+}
+
+static EXECUTOR: Forever<Executor> = Forever::new();
+
+fn main() {
+    env_logger::builder()
+        .filter_level(log::LevelFilter::Debug)
+        .filter_module("async_io", log::LevelFilter::Info)
+        .format_timestamp_nanos()
+        .init();
+
+    let executor = EXECUTOR.put(Executor::new());
+    executor.run(|spawner| {
+        spawner.spawn(main_task(spawner)).unwrap();
+    });
+}