diff --git a/rtic-channel/src/lib.rs b/rtic-channel/src/lib.rs index 6f816b5755..3cee78be5c 100644 --- a/rtic-channel/src/lib.rs +++ b/rtic-channel/src/lib.rs @@ -119,6 +119,14 @@ macro_rules! make_channel { /// Error state for when the receiver has been dropped. pub struct NoReceiver(pub T); +/// Errors that 'try_send` can have. +pub enum TrySendError { + /// Error state for when the receiver has been dropped. + NoReceiver(T), + /// Error state when the queue is full. + Full(T), +} + impl core::fmt::Debug for NoReceiver where T: core::fmt::Debug, @@ -128,6 +136,32 @@ where } } +impl core::fmt::Debug for TrySendError +where + T: core::fmt::Debug, +{ + fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result { + match self { + TrySendError::NoReceiver(v) => write!(f, "NoReceiver({:?})", v), + TrySendError::Full(v) => write!(f, "Full({:?})", v), + } + } +} + +impl PartialEq for TrySendError +where + T: PartialEq, +{ + fn eq(&self, other: &Self) -> bool { + match (self, other) { + (TrySendError::NoReceiver(v1), TrySendError::NoReceiver(v2)) => v1.eq(v2), + (TrySendError::NoReceiver(_), TrySendError::Full(_)) => false, + (TrySendError::Full(_), TrySendError::NoReceiver(_)) => false, + (TrySendError::Full(v1), TrySendError::Full(v2)) => v1.eq(v2), + } + } +} + /// A `Sender` can send to the channel and can be cloned. pub struct Sender<'a, T, const N: usize>(&'a Channel); @@ -178,18 +212,22 @@ impl<'a, T, const N: usize> Sender<'a, T, N> { } /// Try to send a value, non-blocking. If the channel is full this will return an error. - /// Note; this does not check if the channel is closed. - pub fn try_send(&mut self, val: T) -> Result<(), T> { + pub fn try_send(&mut self, val: T) -> Result<(), TrySendError> { // If the wait queue is not empty, we can't try to push into the queue. if !self.0.wait_queue.is_empty() { - return Err(val); + return Err(TrySendError::Full(val)); + } + + // No receiver available. + if self.is_closed() { + return Err(TrySendError::NoReceiver(val)); } let idx = if let Some(idx) = critical_section::with(|cs| self.0.access(cs).freeq.pop_front()) { idx } else { - return Err(val); + return Err(TrySendError::Full(val)); }; self.send_footer(idx, val); @@ -330,19 +368,18 @@ impl<'a, T, const N: usize> core::fmt::Debug for Receiver<'a, T, N> { } } -/// Error state for when all senders has been dropped. -pub struct NoSender; - -impl core::fmt::Debug for NoSender { - fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result { - write!(f, "NoSender") - } +/// Possible receive errors. +#[derive(Debug, PartialEq, Eq)] +pub enum ReceiveError { + /// Error state for when all senders has been dropped. + NoSender, + /// Error state for when the queue is empty. + Empty, } impl<'a, T, const N: usize> Receiver<'a, T, N> { /// Receives a value if there is one in the channel, non-blocking. - /// Note; this does not check if the channel is closed. - pub fn try_recv(&mut self) -> Option { + pub fn try_recv(&mut self) -> Result { // Try to get a ready slot. let ready_slot = critical_section::with(|cs| self.0.access(cs).readyq.pop_front()); @@ -363,15 +400,19 @@ impl<'a, T, const N: usize> Receiver<'a, T, N> { wait_head.wake(); } - Some(r) + Ok(r) } else { - None + if self.is_closed() { + Err(ReceiveError::NoSender) + } else { + Err(ReceiveError::Empty) + } } } /// Receives a value, waiting if the queue is empty. /// If all senders are dropped this will error with `NoSender`. - pub async fn recv(&mut self) -> Result { + pub async fn recv(&mut self) -> Result { // There was nothing in the queue, setup the waiting. poll_fn(|cx| { // Register waker. @@ -379,13 +420,14 @@ impl<'a, T, const N: usize> Receiver<'a, T, N> { self.0.receiver_waker.register(cx.waker()); // Try to dequeue. - if let Some(val) = self.try_recv() { - return Poll::Ready(Ok(val)); - } - - // If the queue is empty and there is no sender, return the error. - if self.is_closed() { - return Poll::Ready(Err(NoSender)); + match self.try_recv() { + Ok(val) => { + return Poll::Ready(Ok(val)); + } + Err(ReceiveError::NoSender) => { + return Poll::Ready(Err(ReceiveError::NoSender)); + } + _ => {} } Poll::Pending @@ -476,13 +518,13 @@ mod tests { s.try_send(i).unwrap(); } - assert_eq!(s.try_send(11), Err(11)); + assert_eq!(s.try_send(11), Err(TrySendError::Full(11))); for i in 0..10 { assert_eq!(r.try_recv().unwrap(), i); } - assert_eq!(r.try_recv(), None); + assert_eq!(r.try_recv(), Err(ReceiveError::Empty)); } #[test] @@ -493,7 +535,7 @@ mod tests { assert!(r.is_closed()); - assert_eq!(r.try_recv(), None); + assert_eq!(r.try_recv(), Err(ReceiveError::NoSender)); } #[test] @@ -504,7 +546,7 @@ mod tests { assert!(s.is_closed()); - assert_eq!(s.try_send(11), Ok(())); + assert_eq!(s.try_send(11), Err(TrySendError::NoReceiver(11))); } #[tokio::test]