Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 147 insertions, 0 deletions

diff --git a/third_party/rust/socket2/src/sockref.rs b/third_party/rust/socket2/src/sockref.rs
new file mode 100644
index 0000000000..257323beb3
--- /dev/null
+++ b/third_party/rust/socket2/src/sockref.rs
@@ -0,0 +1,147 @@
+use std::fmt;
+use std::marker::PhantomData;
+use std::mem::ManuallyDrop;
+use std::ops::Deref;
+#[cfg(unix)]
+use std::os::unix::io::{AsRawFd, FromRawFd};
+#[cfg(windows)]
+use std::os::windows::io::{AsRawSocket, FromRawSocket};
+
+use crate::Socket;
+
+/// A reference to a [`Socket`] that can be used to configure socket types other
+/// than the `Socket` type itself.
+///
+/// This allows for example a [`TcpStream`], found in the standard library, to
+/// be configured using all the additional methods found in the [`Socket`] API.
+///
+/// `SockRef` can be created from any socket type that implements [`AsRawFd`]
+/// (Unix) or [`AsRawSocket`] (Windows) using the [`From`] implementation, but
+/// the caller must ensure the file descriptor/socket is a valid.
+///
+/// [`TcpStream`]: std::net::TcpStream
+// Don't use intra-doc links because they won't build on every platform.
+/// [`AsRawFd`]: https://doc.rust-lang.org/stable/std/os/unix/io/trait.AsRawFd.html
+/// [`AsRawSocket`]: https://doc.rust-lang.org/stable/std/os/windows/io/trait.AsRawSocket.html
+///
+/// # Examples
+///
+/// Below is an example of converting a [`TcpStream`] into a [`SockRef`].
+///
+/// ```
+/// use std::net::{TcpStream, SocketAddr};
+///
+/// use socket2::SockRef;
+///
+/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
+/// // Create `TcpStream` from the standard library.
+/// let address: SocketAddr = "127.0.0.1:1234".parse()?;
+/// # let b1 = std::sync::Arc::new(std::sync::Barrier::new(2));
+/// # let b2 = b1.clone();
+/// # let handle = std::thread::spawn(move || {
+/// #    let listener = std::net::TcpListener::bind(address).unwrap();
+/// #    b2.wait();
+/// #    let (stream, _) = listener.accept().unwrap();
+/// #    std::thread::sleep(std::time::Duration::from_millis(10));
+/// #    drop(stream);
+/// # });
+/// # b1.wait();
+/// let stream = TcpStream::connect(address)?;
+///
+/// // Create a `SockRef`erence to the stream.
+/// let socket_ref = SockRef::from(&stream);
+/// // Use `Socket::set_nodelay` on the stream.
+/// socket_ref.set_nodelay(true)?;
+/// drop(socket_ref);
+///
+/// assert_eq!(stream.nodelay()?, true);
+/// # handle.join().unwrap();
+/// # Ok(())
+/// # }
+/// ```
+///
+/// Below is an example of **incorrect usage** of `SockRef::from`, which is
+/// currently possible (but not intended and will be fixed in future versions).
+///
+/// ```compile_fail
+/// use socket2::SockRef;
+///
+/// # fn main() -> Result<(), Box<dyn std::error::Error>> {
+/// /// THIS USAGE IS NOT VALID!
+/// let socket_ref = SockRef::from(&123);
+/// // The above line is overseen possibility when using `SockRef::from`, it
+/// // uses the `RawFd` (on Unix), which is a type alias for `c_int`/`i32`,
+/// // which implements `AsRawFd`. However it may be clear that this usage is
+/// // invalid as it doesn't guarantee that `123` is a valid file descriptor.
+///
+/// // Using `Socket::set_nodelay` now will call it on a file descriptor we
+/// // don't own! We don't even not if the file descriptor is valid or a socket.
+/// socket_ref.set_nodelay(true)?;
+/// drop(socket_ref);
+/// # Ok(())
+/// # }
+/// # DO_NOT_COMPILE
+/// ```
+pub struct SockRef<'s> {
+    /// Because this is a reference we don't own the `Socket`, however `Socket`
+    /// closes itself when dropped, so we use `ManuallyDrop` to prevent it from
+    /// closing itself.
+    socket: ManuallyDrop<Socket>,
+    /// Because we don't own the socket we need to ensure the socket remains
+    /// open while we have a "reference" to it, the lifetime `'s` ensures this.
+    _lifetime: PhantomData<&'s Socket>,
+}
+
+impl<'s> Deref for SockRef<'s> {
+    type Target = Socket;
+
+    fn deref(&self) -> &Self::Target {
+        &self.socket
+    }
+}
+
+/// On Windows, a corresponding `From<&impl AsRawSocket>` implementation exists.
+#[cfg(unix)]
+#[cfg_attr(docsrs, doc(cfg(unix)))]
+impl<'s, S> From<&'s S> for SockRef<'s>
+where
+    S: AsRawFd,
+{
+    /// The caller must ensure `S` is actually a socket.
+    fn from(socket: &'s S) -> Self {
+        let fd = socket.as_raw_fd();
+        assert!(fd >= 0);
+        SockRef {
+            socket: ManuallyDrop::new(unsafe { Socket::from_raw_fd(fd) }),
+            _lifetime: PhantomData,
+        }
+    }
+}
+
+/// On Unix, a corresponding `From<&impl AsRawFd>` implementation exists.
+#[cfg(windows)]
+#[cfg_attr(docsrs, doc(cfg(windows)))]
+impl<'s, S> From<&'s S> for SockRef<'s>
+where
+    S: AsRawSocket,
+{
+    /// See the `From<&impl AsRawFd>` implementation.
+    fn from(socket: &'s S) -> Self {
+        let socket = socket.as_raw_socket();
+        assert!(socket != winapi::um::winsock2::INVALID_SOCKET as _);
+        SockRef {
+            socket: ManuallyDrop::new(unsafe { Socket::from_raw_socket(socket) }),
+            _lifetime: PhantomData,
+        }
+    }
+}
+
+impl fmt::Debug for SockRef<'_> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("SockRef")
+            .field("raw", &self.socket.as_raw())
+            .field("local_addr", &self.socket.local_addr().ok())
+            .field("peer_addr", &self.socket.peer_addr().ok())
+            .finish()
+    }
+}