smtpd/onceCloseListerner.go

28 lines
642 B
Go

package smtpd
import (
"net"
"sync"
"sync/atomic"
)
// onceCloseListener wraps a net.Listener, protecting it from
// multiple Close calls.
type onceCloseListener struct {
net.Listener
once sync.Once
closeErr error
}
func (oc *onceCloseListener) Close() error {
oc.once.Do(oc.close)
return oc.closeErr
}
func (oc *onceCloseListener) close() { oc.closeErr = oc.Listener.Close() }
type atomicBool int32
func (b *atomicBool) isSet() bool { return atomic.LoadInt32((*int32)(b)) != 0 }
func (b *atomicBool) setTrue() { atomic.StoreInt32((*int32)(b), 1) }
func (b *atomicBool) setFalse() { atomic.StoreInt32((*int32)(b), 0) }