diff --git a/embassy/src/channel/pubsub/mod.rs b/embassy/src/channel/pubsub/mod.rs index 33440188..fdd67536 100644 --- a/embassy/src/channel/pubsub/mod.rs +++ b/embassy/src/channel/pubsub/mod.rs @@ -1,19 +1,25 @@ //! Implementation of [PubSubChannel], a queue where published messages get received by all subscribers. +#![deny(missing_docs)] + use core::cell::RefCell; use core::fmt::Debug; -use core::future::Future; -use core::marker::PhantomData; -use core::ops::{Deref, DerefMut}; -use core::pin::Pin; use core::task::{Context, Poll, Waker}; use heapless::Deque; +use self::publisher::{ImmediatePub, Pub}; +use self::subscriber::Sub; use crate::blocking_mutex::raw::RawMutex; use crate::blocking_mutex::Mutex; use crate::waitqueue::MultiWakerRegistration; +pub mod publisher; +pub mod subscriber; + +pub use publisher::{DynImmediatePublisher, DynPublisher, ImmediatePublisher, Publisher}; +pub use subscriber::{DynSubscriber, Subscriber}; + /// A broadcast channel implementation where multiple publishers can send messages to multiple subscribers /// /// Any published message can be read by all subscribers. @@ -48,11 +54,7 @@ impl ImmediatePublisher { - ImmediatePublisher(ImmediatePub { - channel: self, - _phantom: Default::default(), - }) + ImmediatePublisher(ImmediatePub::new(self)) } /// Create a new publisher that can only send immediate messages. /// This kind of publisher does not take up a publisher slot. pub fn dyn_immediate_publisher(&self) -> DynImmediatePublisher { - DynImmediatePublisher(ImmediatePub { - channel: self, - _phantom: Default::default(), - }) + DynImmediatePublisher(ImmediatePub::new(self)) } } @@ -340,258 +326,6 @@ impl PubSubSta } } -/// A subscriber to a channel -/// -/// This instance carries a reference to the channel, but uses a trait object for it so that the channel's -/// generics are erased on this subscriber -pub struct Sub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { - /// The message id of the next message we are yet to receive - next_message_id: u64, - /// The channel we are a subscriber to - channel: &'a PSB, - _phantom: PhantomData, -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Sub<'a, PSB, T> { - /// Wait for a published message - pub fn next_message<'s>(&'s mut self) -> SubscriberWaitFuture<'s, 'a, PSB, T> { - SubscriberWaitFuture { subscriber: self } - } - - /// Wait for a published message (ignoring lag results) - pub async fn next_message_pure(&mut self) -> T { - loop { - match self.next_message().await { - WaitResult::Lagged(_) => continue, - WaitResult::Message(message) => break message, - } - } - } - - /// Try to see if there's a published message we haven't received yet. - /// - /// This function does not peek. The message is received if there is one. - pub fn try_next_message(&mut self) -> Option> { - match self.channel.get_message_with_context(&mut self.next_message_id, None) { - Poll::Ready(result) => Some(result), - Poll::Pending => None, - } - } - - /// Try to see if there's a published message we haven't received yet (ignoring lag results). - /// - /// This function does not peek. The message is received if there is one. - pub fn try_next_message_pure(&mut self) -> Option { - loop { - match self.try_next_message() { - Some(WaitResult::Lagged(_)) => continue, - Some(WaitResult::Message(message)) => break Some(message), - None => break None, - } - } - } -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Drop for Sub<'a, PSB, T> { - fn drop(&mut self) { - self.channel.unregister_subscriber(self.next_message_id) - } -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for Sub<'a, PSB, T> {} - -pub struct DynSubscriber<'a, T: Clone>(Sub<'a, dyn PubSubBehavior + 'a, T>); - -impl<'a, T: Clone> Deref for DynSubscriber<'a, T> { - type Target = Sub<'a, dyn PubSubBehavior + 'a, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, T: Clone> DerefMut for DynSubscriber<'a, T> { - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - -pub struct Subscriber<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( - Sub<'a, PubSubChannel, T>, -); - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref - for Subscriber<'a, M, T, CAP, SUBS, PUBS> -{ - type Target = Sub<'a, PubSubChannel, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut - for Subscriber<'a, M, T, CAP, SUBS, PUBS> -{ - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - -/// Warning: The stream implementation ignores lag results and returns all messages. -/// This might miss some messages without you knowing it. -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> futures::Stream for Sub<'a, PSB, T> { - type Item = T; - - fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll> { - match self - .channel - .get_message_with_context(&mut self.next_message_id, Some(cx)) - { - Poll::Ready(WaitResult::Message(message)) => Poll::Ready(Some(message)), - Poll::Ready(WaitResult::Lagged(_)) => { - cx.waker().wake_by_ref(); - Poll::Pending - } - Poll::Pending => Poll::Pending, - } - } -} - -/// A publisher to a channel -/// -/// This instance carries a reference to the channel, but uses a trait object for it so that the channel's -/// generics are erased on this subscriber -pub struct Pub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { - /// The channel we are a publisher for - channel: &'a PSB, - _phantom: PhantomData, -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Pub<'a, PSB, T> { - /// Publish a message right now even when the queue is full. - /// This may cause a subscriber to miss an older message. - pub fn publish_immediate(&self, message: T) { - self.channel.publish_immediate(message) - } - - /// Publish a message. But if the message queue is full, wait for all subscribers to have read the last message - pub fn publish<'s>(&'s self, message: T) -> PublisherWaitFuture<'s, 'a, PSB, T> { - PublisherWaitFuture { - message: Some(message), - publisher: self, - } - } - - /// Publish a message if there is space in the message queue - pub fn try_publish(&self, message: T) -> Result<(), T> { - self.channel.publish_with_context(message, None) - } -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Drop for Pub<'a, PSB, T> { - fn drop(&mut self) { - self.channel.unregister_publisher() - } -} - -pub struct DynPublisher<'a, T: Clone>(Pub<'a, dyn PubSubBehavior + 'a, T>); - -impl<'a, T: Clone> Deref for DynPublisher<'a, T> { - type Target = Pub<'a, dyn PubSubBehavior + 'a, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, T: Clone> DerefMut for DynPublisher<'a, T> { - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - -pub struct Publisher<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( - Pub<'a, PubSubChannel, T>, -); - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref - for Publisher<'a, M, T, CAP, SUBS, PUBS> -{ - type Target = Pub<'a, PubSubChannel, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut - for Publisher<'a, M, T, CAP, SUBS, PUBS> -{ - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - -/// A publisher that can only use the `publish_immediate` function, but it doesn't have to be registered with the channel. -/// (So an infinite amount is possible) -pub struct ImmediatePub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { - /// The channel we are a publisher for - channel: &'a PSB, - _phantom: PhantomData, -} - -impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> ImmediatePub<'a, PSB, T> { - /// Publish the message right now even when the queue is full. - /// This may cause a subscriber to miss an older message. - pub fn publish_immediate(&mut self, message: T) { - self.channel.publish_immediate(message) - } - - /// Publish a message if there is space in the message queue - pub fn try_publish(&self, message: T) -> Result<(), T> { - self.channel.publish_with_context(message, None) - } -} - -pub struct DynImmediatePublisher<'a, T: Clone>(ImmediatePub<'a, dyn PubSubBehavior + 'a, T>); - -impl<'a, T: Clone> Deref for DynImmediatePublisher<'a, T> { - type Target = ImmediatePub<'a, dyn PubSubBehavior + 'a, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, T: Clone> DerefMut for DynImmediatePublisher<'a, T> { - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - -pub struct ImmediatePublisher<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( - ImmediatePub<'a, PubSubChannel, T>, -); - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref - for ImmediatePublisher<'a, M, T, CAP, SUBS, PUBS> -{ - type Target = ImmediatePub<'a, PubSubChannel, T>; - - fn deref(&self) -> &Self::Target { - &self.0 - } -} - -impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut - for ImmediatePublisher<'a, M, T, CAP, SUBS, PUBS> -{ - fn deref_mut(&mut self) -> &mut Self::Target { - &mut self.0 - } -} - /// Error type for the [PubSubChannel] #[derive(Debug, PartialEq, Clone)] pub enum Error { @@ -603,59 +337,29 @@ pub enum Error { MaximumPublishersReached, } +/// 'Middle level' behaviour of the pubsub channel. +/// This trait is used so that Sub and Pub can be generic over the channel. pub trait PubSubBehavior { + /// Try to get a message from the queue with the given message id. + /// + /// If the message is not yet present and a context is given, then its waker is registered in the subsriber wakers. fn get_message_with_context(&self, next_message_id: &mut u64, cx: Option<&mut Context<'_>>) -> Poll>; + /// Try to publish a message to the queue. + /// + /// If the queue is full and a context is given, then its waker is registered in the publisher wakers. fn publish_with_context(&self, message: T, cx: Option<&mut Context<'_>>) -> Result<(), T>; + /// Publish a message immediately fn publish_immediate(&self, message: T); + /// Let the channel know that a subscriber has dropped fn unregister_subscriber(&self, subscriber_next_message_id: u64); + /// Let the channel know that a publisher has dropped fn unregister_publisher(&self); } -/// Future for the subscriber wait action -pub struct SubscriberWaitFuture<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> { - subscriber: &'s mut Sub<'a, PSB, T>, -} - -impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Future for SubscriberWaitFuture<'s, 'a, PSB, T> { - type Output = WaitResult; - - fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll { - self.subscriber - .channel - .get_message_with_context(&mut self.subscriber.next_message_id, Some(cx)) - } -} - -impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for SubscriberWaitFuture<'s, 'a, PSB, T> {} - -/// Future for the publisher wait action -pub struct PublisherWaitFuture<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> { - /// The message we need to publish - message: Option, - publisher: &'s Pub<'a, PSB, T>, -} - -impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Future for PublisherWaitFuture<'s, 'a, PSB, T> { - type Output = (); - - fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll { - let message = self.message.take().unwrap(); - match self.publisher.channel.publish_with_context(message, Some(cx)) { - Ok(()) => Poll::Ready(()), - Err(message) => { - self.message = Some(message); - Poll::Pending - } - } - } -} - -impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for PublisherWaitFuture<'s, 'a, PSB, T> {} - /// The result of the subscriber wait procedure #[derive(Debug, Clone, PartialEq)] pub enum WaitResult { diff --git a/embassy/src/channel/pubsub/publisher.rs b/embassy/src/channel/pubsub/publisher.rs new file mode 100644 index 00000000..89a0b924 --- /dev/null +++ b/embassy/src/channel/pubsub/publisher.rs @@ -0,0 +1,183 @@ +//! Implementation of anything directly publisher related + +use core::marker::PhantomData; +use core::ops::{Deref, DerefMut}; +use core::pin::Pin; +use core::task::{Context, Poll}; + +use futures::Future; + +use super::{PubSubBehavior, PubSubChannel}; +use crate::blocking_mutex::raw::RawMutex; + +/// A publisher to a channel +pub struct Pub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { + /// The channel we are a publisher for + channel: &'a PSB, + _phantom: PhantomData, +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Pub<'a, PSB, T> { + pub(super) fn new(channel: &'a PSB) -> Self { + Self { + channel, + _phantom: Default::default(), + } + } + + /// Publish a message right now even when the queue is full. + /// This may cause a subscriber to miss an older message. + pub fn publish_immediate(&self, message: T) { + self.channel.publish_immediate(message) + } + + /// Publish a message. But if the message queue is full, wait for all subscribers to have read the last message + pub fn publish<'s>(&'s self, message: T) -> PublisherWaitFuture<'s, 'a, PSB, T> { + PublisherWaitFuture { + message: Some(message), + publisher: self, + } + } + + /// Publish a message if there is space in the message queue + pub fn try_publish(&self, message: T) -> Result<(), T> { + self.channel.publish_with_context(message, None) + } +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Drop for Pub<'a, PSB, T> { + fn drop(&mut self) { + self.channel.unregister_publisher() + } +} + +/// A publisher that holds a dynamic reference to the channel +pub struct DynPublisher<'a, T: Clone>(pub(super) Pub<'a, dyn PubSubBehavior + 'a, T>); + +impl<'a, T: Clone> Deref for DynPublisher<'a, T> { + type Target = Pub<'a, dyn PubSubBehavior + 'a, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, T: Clone> DerefMut for DynPublisher<'a, T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// A publisher that holds a generic reference to the channel +pub struct Publisher<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( + pub(super) Pub<'a, PubSubChannel, T>, +); + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref + for Publisher<'a, M, T, CAP, SUBS, PUBS> +{ + type Target = Pub<'a, PubSubChannel, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut + for Publisher<'a, M, T, CAP, SUBS, PUBS> +{ + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// A publisher that can only use the `publish_immediate` function, but it doesn't have to be registered with the channel. +/// (So an infinite amount is possible) +pub struct ImmediatePub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { + /// The channel we are a publisher for + channel: &'a PSB, + _phantom: PhantomData, +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> ImmediatePub<'a, PSB, T> { + pub(super) fn new(channel: &'a PSB) -> Self { + Self { + channel, + _phantom: Default::default(), + } + } + /// Publish the message right now even when the queue is full. + /// This may cause a subscriber to miss an older message. + pub fn publish_immediate(&mut self, message: T) { + self.channel.publish_immediate(message) + } + + /// Publish a message if there is space in the message queue + pub fn try_publish(&self, message: T) -> Result<(), T> { + self.channel.publish_with_context(message, None) + } +} + +/// An immediate publisher that holds a dynamic reference to the channel +pub struct DynImmediatePublisher<'a, T: Clone>(pub(super) ImmediatePub<'a, dyn PubSubBehavior + 'a, T>); + +impl<'a, T: Clone> Deref for DynImmediatePublisher<'a, T> { + type Target = ImmediatePub<'a, dyn PubSubBehavior + 'a, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, T: Clone> DerefMut for DynImmediatePublisher<'a, T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// An immediate publisher that holds a generic reference to the channel +pub struct ImmediatePublisher<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( + pub(super) ImmediatePub<'a, PubSubChannel, T>, +); + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref + for ImmediatePublisher<'a, M, T, CAP, SUBS, PUBS> +{ + type Target = ImmediatePub<'a, PubSubChannel, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut + for ImmediatePublisher<'a, M, T, CAP, SUBS, PUBS> +{ + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// Future for the publisher wait action +pub struct PublisherWaitFuture<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> { + /// The message we need to publish + message: Option, + publisher: &'s Pub<'a, PSB, T>, +} + +impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Future for PublisherWaitFuture<'s, 'a, PSB, T> { + type Output = (); + + fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll { + let message = self.message.take().unwrap(); + match self.publisher.channel.publish_with_context(message, Some(cx)) { + Ok(()) => Poll::Ready(()), + Err(message) => { + self.message = Some(message); + Poll::Pending + } + } + } +} + +impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for PublisherWaitFuture<'s, 'a, PSB, T> {} diff --git a/embassy/src/channel/pubsub/subscriber.rs b/embassy/src/channel/pubsub/subscriber.rs new file mode 100644 index 00000000..23c4938d --- /dev/null +++ b/embassy/src/channel/pubsub/subscriber.rs @@ -0,0 +1,153 @@ +//! Implementation of anything directly subscriber related + +use core::marker::PhantomData; +use core::ops::{Deref, DerefMut}; +use core::pin::Pin; +use core::task::{Context, Poll}; + +use futures::Future; + +use super::{PubSubBehavior, PubSubChannel, WaitResult}; +use crate::blocking_mutex::raw::RawMutex; + +/// A subscriber to a channel +pub struct Sub<'a, PSB: PubSubBehavior + ?Sized, T: Clone> { + /// The message id of the next message we are yet to receive + next_message_id: u64, + /// The channel we are a subscriber to + channel: &'a PSB, + _phantom: PhantomData, +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Sub<'a, PSB, T> { + pub(super) fn new(next_message_id: u64, channel: &'a PSB) -> Self { + Self { + next_message_id, + channel, + _phantom: Default::default(), + } + } + + /// Wait for a published message + pub fn next_message<'s>(&'s mut self) -> SubscriberWaitFuture<'s, 'a, PSB, T> { + SubscriberWaitFuture { subscriber: self } + } + + /// Wait for a published message (ignoring lag results) + pub async fn next_message_pure(&mut self) -> T { + loop { + match self.next_message().await { + WaitResult::Lagged(_) => continue, + WaitResult::Message(message) => break message, + } + } + } + + /// Try to see if there's a published message we haven't received yet. + /// + /// This function does not peek. The message is received if there is one. + pub fn try_next_message(&mut self) -> Option> { + match self.channel.get_message_with_context(&mut self.next_message_id, None) { + Poll::Ready(result) => Some(result), + Poll::Pending => None, + } + } + + /// Try to see if there's a published message we haven't received yet (ignoring lag results). + /// + /// This function does not peek. The message is received if there is one. + pub fn try_next_message_pure(&mut self) -> Option { + loop { + match self.try_next_message() { + Some(WaitResult::Lagged(_)) => continue, + Some(WaitResult::Message(message)) => break Some(message), + None => break None, + } + } + } +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Drop for Sub<'a, PSB, T> { + fn drop(&mut self) { + self.channel.unregister_subscriber(self.next_message_id) + } +} + +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for Sub<'a, PSB, T> {} + +/// Warning: The stream implementation ignores lag results and returns all messages. +/// This might miss some messages without you knowing it. +impl<'a, PSB: PubSubBehavior + ?Sized, T: Clone> futures::Stream for Sub<'a, PSB, T> { + type Item = T; + + fn poll_next(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll> { + match self + .channel + .get_message_with_context(&mut self.next_message_id, Some(cx)) + { + Poll::Ready(WaitResult::Message(message)) => Poll::Ready(Some(message)), + Poll::Ready(WaitResult::Lagged(_)) => { + cx.waker().wake_by_ref(); + Poll::Pending + } + Poll::Pending => Poll::Pending, + } + } +} + +/// A subscriber that holds a dynamic reference to the channel +pub struct DynSubscriber<'a, T: Clone>(pub(super) Sub<'a, dyn PubSubBehavior + 'a, T>); + +impl<'a, T: Clone> Deref for DynSubscriber<'a, T> { + type Target = Sub<'a, dyn PubSubBehavior + 'a, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, T: Clone> DerefMut for DynSubscriber<'a, T> { + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// A subscriber that holds a generic reference to the channel +pub struct Subscriber<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize>( + pub(super) Sub<'a, PubSubChannel, T>, +); + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> Deref + for Subscriber<'a, M, T, CAP, SUBS, PUBS> +{ + type Target = Sub<'a, PubSubChannel, T>; + + fn deref(&self) -> &Self::Target { + &self.0 + } +} + +impl<'a, M: RawMutex, T: Clone, const CAP: usize, const SUBS: usize, const PUBS: usize> DerefMut + for Subscriber<'a, M, T, CAP, SUBS, PUBS> +{ + fn deref_mut(&mut self) -> &mut Self::Target { + &mut self.0 + } +} + +/// Future for the subscriber wait action +pub struct SubscriberWaitFuture<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> { + subscriber: &'s mut Sub<'a, PSB, T>, +} + +impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Future for SubscriberWaitFuture<'s, 'a, PSB, T> { + type Output = WaitResult; + + fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll { + self.subscriber + .channel + .get_message_with_context(&mut self.subscriber.next_message_id, Some(cx)) + } +} + +impl<'s, 'a, PSB: PubSubBehavior + ?Sized, T: Clone> Unpin for SubscriberWaitFuture<'s, 'a, PSB, T> {}