restic/src/restic/backend/semaphore.go

24 lines
449 B
Go

package backend
// Semaphore limits access to a restricted resource.
type Semaphore struct {
ch chan struct{}
}
// NewSemaphore returns a new semaphore with capacity n.
func NewSemaphore(n int) *Semaphore {
return &Semaphore{
ch: make(chan struct{}, n),
}
}
// GetToken blocks until a Token is available.
func (s *Semaphore) GetToken() {
s.ch <- struct{}{}
}
// ReleaseToken returns a token.
func (s *Semaphore) ReleaseToken() {
<-s.ch
}