Implement AsRawFd for EventLoop<'l, Data>

This should allow inserting one `EventLoop` into the other.

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Unreleased
 
+#### Additions
+
+- Implement `AsRawFd` for `EventLoop<'l, Data>`
+
 #### Bugfixes
 
 - Fix an issue, where id-reuse could execute a PostAction on a newly registered event source

src/loop_logic.rs

@@ -1,6 +1,7 @@
 use std::cell::{Cell, RefCell};
 use std::fmt::Debug;
 use std::os::unix::io::AsFd;
+use std::os::unix::io::{AsRawFd, RawFd};
 use std::rc::Rc;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::Arc;
@@ -671,6 +672,19 @@ impl<'l, Data> EventLoop<'l, Data> {
     }
 }
 
+impl<'l, Data> AsRawFd for EventLoop<'l, Data> {
+    /// Get the underlying raw-fd of the poller.
+    ///
+    /// This could be used to create [`Generic`] source out of the current loop
+    /// and inserting into some other [`EventLoop`]. It's recommended to clone `fd`
+    /// before doing so.
+    ///
+    /// [`Generic`]: crate::generic::Generic
+    fn as_raw_fd(&self) -> RawFd {
+        self.handle.inner.poll.borrow().poller.as_raw_fd()
+    }
+}
+
 #[derive(Clone, Debug)]
 /// The EventIterator is an `Iterator` over the events relevant to a particular source
 /// This type is used in the [`EventSource::before_handle_events`] methods for

src/sys.rs

@@ -180,7 +180,7 @@ pub struct Token {
 /// source and delegate the implementations to it.
 pub struct Poll {
     /// The handle to wepoll/epoll/kqueue/... used to poll for events.
-    poller: Arc<Poller>,
+    pub(crate) poller: Arc<Poller>,
 
     /// The buffer of events returned by the poller.
     events: RefCell<Events>,