Monotonic rewrite (#874)

* Rework timer_queue and monotonic architecture

Goals:
 * make Monotonic purely internal
 * make Monotonic purely tick passed, no fugit involved
 * create a wrapper struct in the user's code via a macro that then
   converts the "now" from the tick based monotonic to a fugit based
   timestamp

We need to proxy the delay functions of the timer queue anyway,
so we could simply perform the conversion in those proxy functions.

* Update cargo.lock

* Update readme of rtic-time

* CI: ESP32: Redact esp_image: Too volatile

* Fixup: Changelog double entry rebase mistake

---------

Co-authored-by: Henrik Tjäder <henrik@tjaders.com>

1 files changed, 113 insertions, 0 deletions

diff --git a/rtic-time/src/monotonic/timer_queue_based_monotonic.rs b/rtic-time/src/monotonic/timer_queue_based_monotonic.rs
new file mode 100644
index 0000000..699958b
--- /dev/null
+++ b/rtic-time/src/monotonic/timer_queue_based_monotonic.rs
@@ -0,0 +1,113 @@
+use crate::{timer_queue::TimerQueueBackend, TimeoutError};
+
+use crate::Monotonic;
+
+/// A [`Monotonic`] that is backed by the [`TimerQueue`](crate::timer_queue::TimerQueue).
+pub trait TimerQueueBasedMonotonic {
+    /// The backend for the timer queue
+    type Backend: TimerQueueBackend;
+
+    /// The type for instant, defining an instant in time.
+    ///
+    /// **Note:** In all APIs in RTIC that use instants from this monotonic, this type will be used.
+    type Instant: TimerQueueBasedInstant<Ticks = <Self::Backend as TimerQueueBackend>::Ticks>
+        + core::ops::Add<Self::Duration, Output = Self::Instant>
+        + core::ops::Sub<Self::Duration, Output = Self::Instant>
+        + core::ops::Sub<Self::Instant, Output = Self::Duration>;
+
+    /// The type for duration, defining a duration of time.
+    ///
+    /// **Note:** In all APIs in RTIC that use duration from this monotonic, this type will be used.
+    type Duration: TimerQueueBasedDuration<Ticks = <Self::Backend as TimerQueueBackend>::Ticks>;
+}
+
+impl<T: TimerQueueBasedMonotonic> Monotonic for T {
+    type Instant = T::Instant;
+    type Duration = T::Duration;
+
+    fn now() -> Self::Instant {
+        Self::Instant::from_ticks(T::Backend::timer_queue().now())
+    }
+
+    async fn delay(duration: Self::Duration) {
+        T::Backend::timer_queue().delay(duration.ticks()).await
+    }
+
+    async fn delay_until(instant: Self::Instant) {
+        T::Backend::timer_queue().delay_until(instant.ticks()).await
+    }
+
+    async fn timeout_at<F: core::future::Future>(
+        instant: Self::Instant,
+        future: F,
+    ) -> Result<F::Output, TimeoutError> {
+        T::Backend::timer_queue()
+            .timeout_at(instant.ticks(), future)
+            .await
+    }
+
+    async fn timeout_after<F: core::future::Future>(
+        duration: Self::Duration,
+        future: F,
+    ) -> Result<F::Output, TimeoutError> {
+        T::Backend::timer_queue()
+            .timeout_after(duration.ticks(), future)
+            .await
+    }
+}
+
+/// An instant that can be used in [`TimerQueueBasedMonotonic`].
+pub trait TimerQueueBasedInstant: Ord + Copy {
+    /// The internal type of the instant
+    type Ticks;
+    /// Convert from ticks to the instant
+    fn from_ticks(ticks: Self::Ticks) -> Self;
+    /// Convert the instant to ticks
+    fn ticks(self) -> Self::Ticks;
+}
+
+/// A duration that can be used in [`TimerQueueBasedMonotonic`].
+pub trait TimerQueueBasedDuration: Copy {
+    /// The internal type of the duration
+    type Ticks;
+    /// Convert the duration to ticks
+    fn ticks(self) -> Self::Ticks;
+}
+
+impl<const NOM: u32, const DENOM: u32> TimerQueueBasedInstant for fugit::Instant<u64, NOM, DENOM> {
+    type Ticks = u64;
+    fn from_ticks(ticks: Self::Ticks) -> Self {
+        Self::from_ticks(ticks)
+    }
+    fn ticks(self) -> Self::Ticks {
+        Self::ticks(&self)
+    }
+}
+
+impl<const NOM: u32, const DENOM: u32> TimerQueueBasedInstant for fugit::Instant<u32, NOM, DENOM> {
+    type Ticks = u32;
+    fn from_ticks(ticks: Self::Ticks) -> Self {
+        Self::from_ticks(ticks)
+    }
+    fn ticks(self) -> Self::Ticks {
+        Self::ticks(&self)
+    }
+}
+
+impl<const NOM: u32, const DENOM: u32> TimerQueueBasedDuration
+    for fugit::Duration<u64, NOM, DENOM>
+{
+    type Ticks = u64;
+    fn ticks(self) -> Self::Ticks {
+        Self::ticks(&self)
+    }
+}
+
+impl<const NOM: u32, const DENOM: u32> TimerQueueBasedDuration
+    for fugit::Duration<u32, NOM, DENOM>
+{
+    type Ticks = u32;
+    fn ticks(self) -> Self::Ticks {
+        Self::ticks(&self)
+    }
+}