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|
package proton
import (
"math/rand"
"time"
"github.com/ProtonMail/gluon/async"
)
type Ticker struct {
C chan time.Time
stopCh chan struct{}
doneCh chan struct{}
}
// NewTicker returns a new ticker that ticks at a random time between period and period+jitter.
// It can be stopped by closing calling Stop().
func NewTicker(period, jitter time.Duration, panicHandler async.PanicHandler) *Ticker {
t := &Ticker{
C: make(chan time.Time),
stopCh: make(chan struct{}),
doneCh: make(chan struct{}),
}
go func() {
defer async.HandlePanic(panicHandler)
defer close(t.doneCh)
for {
select {
case <-t.stopCh:
return
case <-time.After(withJitter(period, jitter)):
select {
case <-t.stopCh:
return
case t.C <- time.Now():
// ...
}
}
}
}()
return t
}
func (t *Ticker) Stop() {
close(t.stopCh)
<-t.doneCh
}
func withJitter(period, jitter time.Duration) time.Duration {
if jitter == 0 {
return period
}
return period + time.Duration(rand.Int63n(int64(jitter)))
}
|
