WIP: Implement FromRawFd for TcpStreamNew

src/net/tcp.rs

@@ -462,7 +462,10 @@ impl Future for TcpStreamConnect {
 #[cfg(unix)]
 mod sys {
     use std::os::unix::prelude::*;
-    use super::{TcpStream, TcpListener};
+    use std::io;
+    use super::{TcpStream, TcpStreamNew, TcpListener};
+    use futures::{Future, failed};
+    use mio;
 
     impl AsRawFd for TcpStream {
         fn as_raw_fd(&self) -> RawFd {
@@ -475,6 +478,25 @@ mod sys {
             self.io.get_ref().as_raw_fd()
         }
     }
+
+    impl FromRawFd for TcpStreamNew {
+        unsafe fn from_raw_fd(fd: RawFd) -> TcpStreamNew {
+            let future = match ::reactor::current() {
+                Some(handle) => {
+                    let tcp = mio::tcp::TcpStream::from_raw_fd(fd);
+                    TcpStream::new(tcp, &handle)
+                },
+                None => {
+                    let msg = "Could not retrieve a handle to the reactor Core. \
+                                Did you initialise the event loop by running `Core::new()`? \
+                                If so, is it still in scope?";
+                    let error = io::Error::new(io::ErrorKind::Other, msg);
+                    failed::<TcpStream, io::Error>(error).boxed()
+                },
+            };
+            TcpStreamNew { inner: future }
+        }
+    }
 }
 
 #[cfg(windows)]

src/reactor/mod.rs

@@ -647,3 +647,12 @@ impl<F: FnOnce(&Core) + Send + 'static> FnBox for F {
         (*self)(lp)
     }
 }
+
+/// Retrieves a `Handle` for the currently running reactor Core
+pub fn current() -> Option<Handle> {
+    if CURRENT_LOOP.is_set() {
+        CURRENT_LOOP.with(|lp| Some(lp.handle().clone()))
+    } else {
+        None
+    }
+}