mirror of
https://github.com/ceph/ceph-csi.git
synced 2024-11-24 15:20:19 +00:00
62 lines
1.5 KiB
Go
62 lines
1.5 KiB
Go
/*
|
|
*
|
|
* Copyright 2018 gRPC authors.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*
|
|
*/
|
|
|
|
// Package grpcsync implements additional synchronization primitives built upon
|
|
// the sync package.
|
|
package grpcsync
|
|
|
|
import (
|
|
"sync"
|
|
"sync/atomic"
|
|
)
|
|
|
|
// Event represents a one-time event that may occur in the future.
|
|
type Event struct {
|
|
fired int32
|
|
c chan struct{}
|
|
o sync.Once
|
|
}
|
|
|
|
// Fire causes e to complete. It is safe to call multiple times, and
|
|
// concurrently. It returns true iff this call to Fire caused the signaling
|
|
// channel returned by Done to close.
|
|
func (e *Event) Fire() bool {
|
|
ret := false
|
|
e.o.Do(func() {
|
|
atomic.StoreInt32(&e.fired, 1)
|
|
close(e.c)
|
|
ret = true
|
|
})
|
|
return ret
|
|
}
|
|
|
|
// Done returns a channel that will be closed when Fire is called.
|
|
func (e *Event) Done() <-chan struct{} {
|
|
return e.c
|
|
}
|
|
|
|
// HasFired returns true if Fire has been called.
|
|
func (e *Event) HasFired() bool {
|
|
return atomic.LoadInt32(&e.fired) == 1
|
|
}
|
|
|
|
// NewEvent returns a new, ready-to-use Event.
|
|
func NewEvent() *Event {
|
|
return &Event{c: make(chan struct{})}
|
|
}
|