65 lines
892 B
Go
65 lines
892 B
Go
/* SPDX-License-Identifier: GPL-2.0
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*
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* Copyright (C) 2017-2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
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*/
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package main
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type Signal struct {
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enabled AtomicBool
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C chan struct{}
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}
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func NewSignal() (s Signal) {
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s.C = make(chan struct{}, 1)
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s.Enable()
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return
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}
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func (s *Signal) Close() {
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close(s.C)
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}
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func (s *Signal) Disable() {
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s.enabled.Set(false)
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s.Clear()
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}
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func (s *Signal) Enable() {
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s.enabled.Set(true)
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}
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/* Unblock exactly one listener
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*/
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func (s *Signal) Send() {
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if s.enabled.Get() {
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select {
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case s.C <- struct{}{}:
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default:
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}
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}
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}
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/* Clear the signal if already fired
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*/
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func (s Signal) Clear() {
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select {
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case <-s.C:
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default:
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}
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}
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/* Unblocks all listeners (forever)
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*/
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func (s Signal) Broadcast() {
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if s.enabled.Get() {
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close(s.C)
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}
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}
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/* Wait for the signal
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*/
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func (s Signal) Wait() chan struct{} {
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return s.C
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}
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