naive-timer

A minimal naive timer for embedded platforms in Rust (no_std + alloc).

NOTE: We need to use a nightly version of Rust.

Code

The naive-timer is really naive, that it only has 30 lines of code.

```rust use alloc::boxed::Box; use alloc::collections::BTreeMap; use core::time::Duration;

/// A naive timer.

[derive(Default)]

pub struct Timer { events: BTreeMap, }

/// The type of callback function. type Callback = Box;

impl Timer { /// Add a timer. /// /// The callback will be called on timer expired after deadline. pub fn add( &mut self, mut deadline: Duration, callback: impl FnOnce(Duration) + Send + Sync + 'static, ) { while self.events.containskey(&deadline) { deadline += Duration::fromnanos(1); } self.events.insert(deadline, Box::new(callback)); }

/// Expire timers.
///
/// Given the current time `now`, trigger and remove all expired timers.
pub fn expire(&mut self, now: Duration) {
    while let Some(entry) = self.events.first_entry() {
        if *entry.key() > now {
            return;
        }
        let (_, callback) = entry.remove_entry();
        callback(now);
    }
}

} ```

That's ALL.

License

The code in this repository is licensed under the MIT License.