From 14f42a9aa27fff2ca8579153ed79b845627835df Mon Sep 17 00:00:00 2001
From: Colin Walters <walters@verbum.org>
Date: Mon, 9 Mar 2026 17:42:03 +0000
Subject: [PATCH] activation: Implement From<FileDescriptor> for OwnedFd

I think this crate predates I/O safety in std, but now that `OwnedFd`
is part of std we can use it.

I want to have most of my crates use `#[forbid(unsafe_code)]` and this
helps.

Assisted-by: OpenCode (claude-opus-4-6)
Signed-off-by: Colin Walters <walters@verbum.org>
---
 src/activation.rs | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/src/activation.rs b/src/activation.rs
index adbd478..fae8bfb 100644
--- a/src/activation.rs
+++ b/src/activation.rs
@@ -5,7 +5,7 @@ use nix::sys::socket::{AddressFamily, SockaddrLike, SockaddrStorage};
 use nix::sys::stat::fstat;
 use std::convert::TryFrom;
 use std::env;
-use std::os::unix::io::{IntoRawFd, RawFd};
+use std::os::unix::io::{FromRawFd, IntoRawFd, OwnedFd, RawFd};
 use std::process;
 
 /// Minimum FD number used by systemd for passing sockets.
@@ -271,6 +271,14 @@ impl IntoRawFd for FileDescriptor {
     }
 }
 
+impl From<FileDescriptor> for OwnedFd {
+    fn from(fd: FileDescriptor) -> Self {
+        // SAFETY: FileDescriptor owns its fd, and IntoRawFd consumes it,
+        // so we have exclusive ownership of the raw fd at this point.
+        unsafe { OwnedFd::from_raw_fd(fd.into_raw_fd()) }
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;