Add TcpListener::from_std

Converts a TcpListener from std lib to Heph's version.

rt/src/net/tcp/listener.rs

@@ -147,6 +147,18 @@ impl TcpListener {
         Ok(socket)
     }
 
+    /// Converts a [`std::net::TcpListener`] to a [`heph_rt::net::TcpListener`].
+    ///
+    /// [`heph_rt::net::TcpListener`]: TcpListener
+    pub fn from_std<RT>(rt: &RT, listener: std::net::TcpListener) -> TcpListener
+    where
+        RT: Access,
+    {
+        TcpListener {
+            fd: AsyncFd::new(listener.into(), rt.submission_queue()),
+        }
+    }
+
     /// Returns the local socket address of this listener.
     pub fn local_addr(&self) -> io::Result<SocketAddr> {
         self.with_ref(|socket| socket.local_addr().and_then(convert_address))

rt/tests/functional/tcp/listener.rs

@@ -1,3 +1,4 @@
+use std::io;
 use std::net::SocketAddr;
 use std::time::Duration;
 
@@ -6,7 +7,7 @@ use heph::supervisor::NoSupervisor;
 use heph::ActorRef;
 use heph_rt::net::{TcpListener, TcpStream};
 use heph_rt::spawn::ActorOptions;
-use heph_rt::test::{join, join_many, try_spawn_local};
+use heph_rt::test::{block_on_local_actor, join, join_many, try_spawn_local};
 use heph_rt::util::next;
 use heph_rt::{self as rt, ThreadLocal};
 
@@ -70,6 +71,23 @@ fn ttl() {
     join(&actor_ref, Duration::from_secs(1)).unwrap();
 }
 
+#[test]
+fn listener_from_std() {
+    async fn actor(ctx: actor::Context<!, ThreadLocal>) -> io::Result<()> {
+        let listener = std::net::TcpListener::bind(any_local_address())?;
+        let listener = TcpListener::from_std(ctx.runtime_ref(), listener);
+
+        let initial = listener.ttl()?;
+        let expected = initial + 10;
+        listener.set_ttl(expected)?;
+        assert_eq!(listener.ttl()?, expected);
+
+        Ok(())
+    }
+
+    block_on_local_actor(actor_fn(actor), ()).unwrap();
+}
+
 const DATA: &[u8] = b"Hello world";
 
 async fn stream_actor<RT>(mut ctx: actor::Context<SocketAddr, RT>)