wip

tun-async/Cargo.toml

@@ -3,7 +3,11 @@ name = "tun-async"
 version = "0.1.0"
 edition = "2021"
 
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+[features]
+default = ["tokio"]
+tokio = ["dep:tokio"]
 
 [dependencies]
-tun = { version = "0.1", path = "../tun" }
+fehler = "1.0"
+tun = { path = "../tun" }
+tokio = { version = "1.0", features = ["net"], optional = true }

tun-async/src/lib.rs

@@ -1,14 +1,5 @@
-pub fn add(left: usize, right: usize) -> usize {
-    left + right
-}
+#[cfg(feature = "tokio")]
+#[path = "tokio/mod.rs"]
+pub(crate) mod imp;
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn it_works() {
-        let result = add(2, 2);
-        assert_eq!(result, 4);
-    }
-}
+pub use imp::TunQueue;

tun-async/src/tokio/mod.rs

@@ -0,0 +1,29 @@
+use fehler::throws;
+use std::{
+    io::{self, Error},
+    mem::MaybeUninit,
+};
+use tokio::io::unix::AsyncFd;
+
+pub struct TunQueue {
+    io: AsyncFd<tun::TunQueue>,
+}
+
+impl TunQueue {
+    #[throws]
+    pub fn from_queue(queue: tun::TunQueue) -> Self {
+        Self {
+            io: AsyncFd::new(queue)?,
+        }
+    }
+
+    pub async fn try_recv(&self, buf: &mut [MaybeUninit<u8>]) -> io::Result<usize> {
+        loop {
+            let mut guard = self.io.readable().await?;
+            match guard.try_io(|inner| inner.get_ref().recv(buf)) {
+                Ok(result) => return result,
+                Err(..) => continue,
+            }
+        }
+    }
+}