From c52a08276ff622ea24536cd44e707de63393f92c Mon Sep 17 00:00:00 2001
From: q191201771 <191201771@qq.com>
Date: Mon, 22 Aug 2022 20:17:28 +0800
Subject: [PATCH] =?UTF-8?q?[feat]=20nazasync:=20=E5=A2=9E=E5=8A=A0?=
 =?UTF-8?q?=E4=B8=80=E4=B8=AA=E7=AB=9E=E4=BA=89=E5=A4=B1=E8=B4=A5=E6=97=B6?=
 =?UTF-8?q?=E9=9D=9E=E9=98=BB=E5=A1=9E=E7=9A=84Once?=
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---
 pkg/nazasync/once.go | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 pkg/nazasync/once.go

diff --git a/pkg/nazasync/once.go b/pkg/nazasync/once.go
new file mode 100644
index 0000000..db8a442
--- /dev/null
+++ b/pkg/nazasync/once.go
@@ -0,0 +1,32 @@
+// Copyright 2022, Chef.  All rights reserved.
+// https://github.com/q191201771/naza
+//
+// Use of this source code is governed by a MIT-style license
+// that can be found in the License file.
+//
+// Author: Chef (191201771@qq.com)
+
+package nazasync
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+type StdOnce struct {
+	core sync.Once
+}
+
+func (o *StdOnce) Do(f func()) {
+	o.core.Do(f)
+}
+
+type NonblockingOnce struct {
+	done uint32
+}
+
+func (o *NonblockingOnce) Do(f func()) {
+	if atomic.CompareAndSwapUint32(&o.done, 0, 1) {
+		f()
+	}
+}