feat: Add embassy-based sleeper for no_std (#173)

backon/Cargo.toml

@@ -25,9 +25,11 @@ std = ["fastrand/std"]
 std-blocking-sleep = []
 gloo-timers-sleep = ["gloo-timers/futures"]
 tokio-sleep = ["tokio/time"]
+embassy-sleep = ["embassy-time"]
 
 [dependencies]
 fastrand = { version = "2", default-features = false }
+embassy-time = { version = "0.3", optional = true }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 tokio = { version = "1", optional = true }

backon/src/embassy_timer_sleep.rs

@@ -0,0 +1,20 @@
+use crate::{BlockingSleeper, Sleeper};
+use core::time::Duration;
+
+/// A no_std async sleeper based on the embassy framework (https://embassy.dev)
+#[derive(Clone, Copy, Debug, Default)]
+pub struct EmbassySleeper;
+
+impl Sleeper for EmbassySleeper {
+    type Sleep = embassy_time::Timer;
+
+    fn sleep(&self, dur: Duration) -> Self::Sleep {
+        embassy_time::Timer::after_millis(dur.as_millis() as u64)
+    }
+}
+
+impl BlockingSleeper for EmbassySleeper {
+    fn sleep(&self, dur: Duration) {
+        embassy_time::block_for(embassy_time::Duration::from_millis(dur.as_millis() as u64));
+    }
+}

backon/src/lib.rs

@@ -45,6 +45,7 @@
 //! |---------------------|--------------------|-------------|---------------|
 //! | [`TokioSleeper`]    | tokio-sleep        | non-wasm32  |  Yes          |
 //! | [`GlooTimersSleep`] | gloo-timers-sleep  |   wasm32    |  Yes          |
+//! | [`EmbassySleep`]    | embassy-sleep      |   no_std    |  Yes          |
 //! | [`StdSleeper`]      | std-blocking-sleep |    std      |  No           |
 //!
 //! ## Custom Sleeper
@@ -184,5 +185,10 @@ pub use blocking_sleep::DefaultBlockingSleeper;
 #[cfg(feature = "std-blocking-sleep")]
 pub use blocking_sleep::StdSleeper;
 
+#[cfg(feature = "embassy-sleep")]
+mod embassy_timer_sleep;
+#[cfg(feature = "embassy-sleep")]
+pub use embassy_timer_sleep::EmbassySleeper;
+
 #[cfg(docsrs)]
 pub mod docs;