From c675208b8a90bee39e99c8cd3bb620b99c439482 Mon Sep 17 00:00:00 2001
From: xoviat <xoviat@users.noreply.github.com>
Date: Fri, 21 Jul 2023 16:10:34 -0500
Subject: [PATCH] wpan: complete prelim. command impl.

---
 embassy-stm32-wpan/src/mac/control.rs | 16 ++++++++++------
 embassy-stm32-wpan/src/mac/runner.rs  |  7 ++++---
 2 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/embassy-stm32-wpan/src/mac/control.rs b/embassy-stm32-wpan/src/mac/control.rs
index fd8c22b2..ded41920 100644
--- a/embassy-stm32-wpan/src/mac/control.rs
+++ b/embassy-stm32-wpan/src/mac/control.rs
@@ -1,5 +1,6 @@
 use core::future::Future;
 use core::task;
+use core::task::Poll;
 
 use embassy_sync::blocking_mutex::raw::CriticalSectionRawMutex;
 use embassy_sync::mutex::MutexGuard;
@@ -7,6 +8,7 @@ use embassy_sync::signal::Signal;
 use futures::FutureExt;
 
 use super::commands::MacCommand;
+use super::event::MacEvent;
 use super::typedefs::MacError;
 use crate::mac::runner::Runner;
 
@@ -62,10 +64,9 @@ impl<'a> EventToken<'a> {
 }
 
 impl<'a> Future for EventToken<'a> {
-    // TODO: output something
-    type Output = ();
+    type Output = MacEvent<'a>;
 
-    fn poll(self: core::pin::Pin<&mut Self>, cx: &mut task::Context<'_>) -> task::Poll<Self::Output> {
+    fn poll(self: core::pin::Pin<&mut Self>, cx: &mut task::Context<'_>) -> Poll<Self::Output> {
         self.get_mut().runner.rx_event_channel.lock(|s| {
             let signal = s.borrow_mut();
             let signal = match &*signal {
@@ -73,10 +74,13 @@ impl<'a> Future for EventToken<'a> {
                 _ => unreachable!(),
             };
 
-            let _ = signal.wait().poll_unpin(cx);
-        });
+            let result = match signal.wait().poll_unpin(cx) {
+                Poll::Ready(mac_event) => Poll::Ready(mac_event),
+                Poll::Pending => Poll::Pending,
+            };
 
-        todo!()
+            result
+        })
     }
 }
 
diff --git a/embassy-stm32-wpan/src/mac/runner.rs b/embassy-stm32-wpan/src/mac/runner.rs
index f964d6b3..482321b9 100644
--- a/embassy-stm32-wpan/src/mac/runner.rs
+++ b/embassy-stm32-wpan/src/mac/runner.rs
@@ -13,12 +13,13 @@ use crate::mac::typedefs::{AddressMode, MacAddress, PanId, SecurityLevel};
 use crate::mac::MTU;
 use crate::sub::mac::Mac;
 
+type ZeroCopyPubSub<M, T> = blocking_mutex::Mutex<M, RefCell<Option<Signal<NoopRawMutex, T>>>>;
+
 pub struct Runner<'a> {
     pub(crate) mac_subsystem: Mac,
-
     // rx event backpressure is already provided through the MacEvent drop mechanism
-    pub(crate) rx_event_channel:
-        blocking_mutex::Mutex<CriticalSectionRawMutex, RefCell<Option<Signal<NoopRawMutex, MacEvent<'a>>>>>,
+    // therefore, we don't need to worry about overwriting events
+    pub(crate) rx_event_channel: ZeroCopyPubSub<CriticalSectionRawMutex, MacEvent<'a>>,
     pub(crate) read_mutex: Mutex<CriticalSectionRawMutex, ()>,
     pub(crate) write_mutex: Mutex<CriticalSectionRawMutex, ()>,
     pub(crate) rx_channel: Channel<CriticalSectionRawMutex, MacEvent<'a>, 1>,