feat: support unix sockets (#145)

src/unix.rs

@@ -0,0 +1,31 @@
+use hyper::server::accept::Accept;
+use tokio::net::UnixListener;
+
+use std::pin::Pin;
+use std::task::{Context, Poll};
+
+pub struct UnixAcceptor {
+    inner: UnixListener,
+}
+
+impl UnixAcceptor {
+    pub fn from_listener(listener: UnixListener) -> Self {
+        Self { inner: listener }
+    }
+}
+
+impl Accept for UnixAcceptor {
+    type Conn = tokio::net::UnixStream;
+    type Error = std::io::Error;
+
+    fn poll_accept(
+        self: Pin<&mut Self>,
+        cx: &mut Context<'_>,
+    ) -> Poll<Option<Result<Self::Conn, Self::Error>>> {
+        match self.inner.poll_accept(cx) {
+            Poll::Pending => Poll::Pending,
+            Poll::Ready(Ok((socket, _addr))) => Poll::Ready(Some(Ok(socket))),
+            Poll::Ready(Err(err)) => Poll::Ready(Some(Err(err))),
+        }
+    }
+}