From db238ed17ffacc08ab491cdb65511648bf2dbda0 Mon Sep 17 00:00:00 2001
From: Kirill Chibisov <contact@kchibisov.com>
Date: Mon, 9 Oct 2023 20:44:22 +0400
Subject: [PATCH] Implement `AsRawFd` for `EventLoop<'l, Data>`

This should allow inserting one `EventLoop` into the other.
---
 CHANGELOG.md      |  4 ++++
 src/loop_logic.rs | 14 ++++++++++++++
 src/sys.rs        |  2 +-
 3 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index dc6e702c..71001277 100644
--- a/CHANGELOG.md
+++ b/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
diff --git a/src/loop_logic.rs b/src/loop_logic.rs
index 258848c5..dca97fb6 100644
--- a/src/loop_logic.rs
+++ b/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
diff --git a/src/sys.rs b/src/sys.rs
index 35e39fb3..dd2b94d7 100644
--- a/src/sys.rs
+++ b/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>,