From ef473827a2beaca120f45fbe490f84a0be7d381d Mon Sep 17 00:00:00 2001
From: Artur Kowalski <arturkow2000@gmail.com>
Date: Thu, 11 Aug 2022 15:52:32 +0200
Subject: [PATCH] Remove UdpIo struct

UdpIo was shared by split sender/receives halves. Since split() API is
no more UdpIo is not needed and its APIs may be moved into UdpSocket.
---
 embassy-net/src/udp.rs | 98 ++++++++++++++++++------------------------
 1 file changed, 41 insertions(+), 57 deletions(-)

diff --git a/embassy-net/src/udp.rs b/embassy-net/src/udp.rs
index ee90c3010..78b09a492 100644
--- a/embassy-net/src/udp.rs
+++ b/embassy-net/src/udp.rs
@@ -27,7 +27,8 @@ pub enum Error {
 }
 
 pub struct UdpSocket<'a> {
-    io: UdpIo<'a>,
+    stack: &'a UnsafeCell<SocketStack>,
+    handle: SocketHandle,
 }
 
 impl<'a> UdpSocket<'a> {
@@ -51,10 +52,8 @@ impl<'a> UdpSocket<'a> {
         ));
 
         Self {
-            io: UdpIo {
-                stack: &stack.socket,
-                handle,
-            },
+            stack: &stack.socket,
+            handle,
         }
     }
 
@@ -67,64 +66,17 @@ impl<'a> UdpSocket<'a> {
         // safety: not accessed reentrantly.
         if endpoint.port == 0 {
             // If user didn't specify port allocate a dynamic port.
-            endpoint.port = unsafe { &mut *self.io.stack.get() }.get_local_port();
+            endpoint.port = unsafe { &mut *self.stack.get() }.get_local_port();
         }
 
         // safety: not accessed reentrantly.
-        match unsafe { self.io.with_mut(|s, _| s.bind(endpoint)) } {
+        match unsafe { self.with_mut(|s, _| s.bind(endpoint)) } {
             Ok(()) => Ok(()),
             Err(udp::BindError::InvalidState) => Err(BindError::InvalidState),
             Err(udp::BindError::Unaddressable) => Err(BindError::NoRoute),
         }
     }
 
-    pub async fn send_to<T>(&self, buf: &[u8], remote_endpoint: T) -> Result<(), Error>
-    where
-        T: Into<IpEndpoint>,
-    {
-        self.io.write(buf, remote_endpoint.into()).await
-    }
-
-    pub async fn recv_from(&self, buf: &mut [u8]) -> Result<(usize, IpEndpoint), Error> {
-        self.io.read(buf).await
-    }
-
-    pub fn endpoint(&self) -> IpListenEndpoint {
-        unsafe { self.io.with(|s, _| s.endpoint()) }
-    }
-
-    pub fn is_open(&self) -> bool {
-        unsafe { self.io.with(|s, _| s.is_open()) }
-    }
-
-    pub fn close(&mut self) {
-        unsafe { self.io.with_mut(|s, _| s.close()) }
-    }
-
-    pub fn may_send(&self) -> bool {
-        unsafe { self.io.with(|s, _| s.can_send()) }
-    }
-
-    pub fn may_recv(&self) -> bool {
-        unsafe { self.io.with(|s, _| s.can_recv()) }
-    }
-}
-
-impl Drop for UdpSocket<'_> {
-    fn drop(&mut self) {
-        // safety: not accessed reentrantly.
-        let s = unsafe { &mut *self.io.stack.get() };
-        s.sockets.remove(self.io.handle);
-    }
-}
-
-#[derive(Copy, Clone)]
-pub struct UdpIo<'a> {
-    stack: &'a UnsafeCell<SocketStack>,
-    handle: SocketHandle,
-}
-
-impl UdpIo<'_> {
     /// SAFETY: must not call reentrantly.
     unsafe fn with<R>(&self, f: impl FnOnce(&udp::Socket, &Interface) -> R) -> R {
         let s = &*self.stack.get();
@@ -141,7 +93,7 @@ impl UdpIo<'_> {
         res
     }
 
-    async fn read(&self, buf: &mut [u8]) -> Result<(usize, IpEndpoint), Error> {
+    pub async fn recv_from(&self, buf: &mut [u8]) -> Result<(usize, IpEndpoint), Error> {
         poll_fn(move |cx| unsafe {
             self.with_mut(|s, _| match s.recv_slice(buf) {
                 Ok(x) => Poll::Ready(Ok(x)),
@@ -156,9 +108,13 @@ impl UdpIo<'_> {
         .await
     }
 
-    async fn write(&self, buf: &[u8], ep: IpEndpoint) -> Result<(), Error> {
+    pub async fn send_to<T>(&self, buf: &[u8], remote_endpoint: T) -> Result<(), Error>
+    where
+        T: Into<IpEndpoint>,
+    {
+        let remote_endpoint = remote_endpoint.into();
         poll_fn(move |cx| unsafe {
-            self.with_mut(|s, _| match s.send_slice(buf, ep) {
+            self.with_mut(|s, _| match s.send_slice(buf, remote_endpoint) {
                 // Entire datagram has been sent
                 Ok(()) => Poll::Ready(Ok(())),
                 Err(udp::SendError::BufferFull) => {
@@ -170,4 +126,32 @@ impl UdpIo<'_> {
         })
         .await
     }
+
+    pub fn endpoint(&self) -> IpListenEndpoint {
+        unsafe { self.with(|s, _| s.endpoint()) }
+    }
+
+    pub fn is_open(&self) -> bool {
+        unsafe { self.with(|s, _| s.is_open()) }
+    }
+
+    pub fn close(&mut self) {
+        unsafe { self.with_mut(|s, _| s.close()) }
+    }
+
+    pub fn may_send(&self) -> bool {
+        unsafe { self.with(|s, _| s.can_send()) }
+    }
+
+    pub fn may_recv(&self) -> bool {
+        unsafe { self.with(|s, _| s.can_recv()) }
+    }
+}
+
+impl Drop for UdpSocket<'_> {
+    fn drop(&mut self) {
+        // safety: not accessed reentrantly.
+        let s = unsafe { &mut *self.stack.get() };
+        s.sockets.remove(self.handle);
+    }
 }