1 use super::MAX_SAFE_MILLIS_DURATION;
2 use crate::time::{Clock, Duration, Instant};
3 
4 /// A structure which handles conversion from Instants to `u64` timestamps.
5 #[derive(Debug)]
6 pub(crate) struct TimeSource {
7     start_time: Instant,
8 }
9 
10 impl TimeSource {
new(clock: &Clock) -> Self11     pub(crate) fn new(clock: &Clock) -> Self {
12         Self {
13             start_time: clock.now(),
14         }
15     }
16 
deadline_to_tick(&self, t: Instant) -> u6417     pub(crate) fn deadline_to_tick(&self, t: Instant) -> u64 {
18         // Round up to the end of a ms
19         self.instant_to_tick(t + Duration::from_nanos(999_999))
20     }
21 
instant_to_tick(&self, t: Instant) -> u6422     pub(crate) fn instant_to_tick(&self, t: Instant) -> u64 {
23         // round up
24         let dur: Duration = t.saturating_duration_since(self.start_time);
25         let ms = dur
26             .as_millis()
27             .try_into()
28             .unwrap_or(MAX_SAFE_MILLIS_DURATION);
29         ms.min(MAX_SAFE_MILLIS_DURATION)
30     }
31 
tick_to_duration(&self, t: u64) -> Duration32     pub(crate) fn tick_to_duration(&self, t: u64) -> Duration {
33         Duration::from_millis(t)
34     }
35 
now(&self, clock: &Clock) -> u6436     pub(crate) fn now(&self, clock: &Clock) -> u64 {
37         self.instant_to_tick(clock.now())
38     }
39 
40     #[cfg(test)]
41     #[allow(dead_code)]
start_time(&self) -> Instant42     pub(super) fn start_time(&self) -> Instant {
43         self.start_time
44     }
45 }
46