From 974332c0ccd64fde54e7714c093b2d40b6b982ef Mon Sep 17 00:00:00 2001
From: wwqgtxx <wwqgtxx@gmail.com>
Date: Tue, 5 Mar 2024 10:57:25 +0800
Subject: [PATCH] chore: rebuild sync.Once visit code

---
 common/net/earlyconn.go   |  6 ++----
 common/once/once_go120.go | 26 ++++++++++++++++++++++++++
 common/once/once_go122.go | 26 ++++++++++++++++++++++++++
 component/mmdb/mmdb.go    |  3 ++-
 4 files changed, 56 insertions(+), 5 deletions(-)
 create mode 100644 common/once/once_go120.go
 create mode 100644 common/once/once_go122.go

diff --git a/common/net/earlyconn.go b/common/net/earlyconn.go
index c9a428194..82d392eeb 100644
--- a/common/net/earlyconn.go
+++ b/common/net/earlyconn.go
@@ -3,10 +3,9 @@ package net
 import (
 	"net"
 	"sync"
-	"sync/atomic"
-	"unsafe"
 
 	"github.com/metacubex/mihomo/common/buf"
+	"github.com/metacubex/mihomo/common/once"
 )
 
 type earlyConn struct {
@@ -44,8 +43,7 @@ func (conn *earlyConn) Upstream() any {
 }
 
 func (conn *earlyConn) Success() bool {
-	// atomic visit sync.Once.done
-	return atomic.LoadUint32((*uint32)(unsafe.Pointer(&conn.resOnce))) == 1 && conn.resErr == nil
+	return once.Done(&conn.resOnce) && conn.resErr == nil
 }
 
 func (conn *earlyConn) ReaderReplaceable() bool {
diff --git a/common/once/once_go120.go b/common/once/once_go120.go
new file mode 100644
index 000000000..51578a2da
--- /dev/null
+++ b/common/once/once_go120.go
@@ -0,0 +1,26 @@
+//go:build !go1.22
+
+package once
+
+import (
+	"sync"
+	"sync/atomic"
+	"unsafe"
+)
+
+type Once struct {
+	done uint32
+	m    sync.Mutex
+}
+
+func Done(once *sync.Once) bool {
+	// atomic visit sync.Once.done
+	return atomic.LoadUint32((*uint32)(unsafe.Pointer(once))) == 1
+}
+
+func Reset(once *sync.Once) {
+	o := (*Once)(unsafe.Pointer(once))
+	o.m.Lock()
+	defer o.m.Unlock()
+	atomic.StoreUint32(&o.done, 0)
+}
diff --git a/common/once/once_go122.go b/common/once/once_go122.go
new file mode 100644
index 000000000..5ff8461d6
--- /dev/null
+++ b/common/once/once_go122.go
@@ -0,0 +1,26 @@
+//go:build go1.22
+
+package once
+
+import (
+	"sync"
+	"sync/atomic"
+	"unsafe"
+)
+
+type Once struct {
+	done atomic.Uint32
+	m    sync.Mutex
+}
+
+func Done(once *sync.Once) bool {
+	// atomic visit sync.Once.done
+	return (*atomic.Uint32)(unsafe.Pointer(once)).Load() == 1
+}
+
+func Reset(once *sync.Once) {
+	o := (*Once)(unsafe.Pointer(once))
+	o.m.Lock()
+	defer o.m.Unlock()
+	o.done.Store(0)
+}
diff --git a/component/mmdb/mmdb.go b/component/mmdb/mmdb.go
index 24edb5e52..66b632beb 100644
--- a/component/mmdb/mmdb.go
+++ b/component/mmdb/mmdb.go
@@ -8,6 +8,7 @@ import (
 	"sync"
 	"time"
 
+	mihomoOnce "github.com/metacubex/mihomo/common/once"
 	mihomoHttp "github.com/metacubex/mihomo/component/http"
 	C "github.com/metacubex/mihomo/constant"
 	"github.com/metacubex/mihomo/log"
@@ -96,5 +97,5 @@ func DownloadMMDB(path string) (err error) {
 }
 
 func Reload() {
-	once = sync.Once{}
+	mihomoOnce.Reset(&once)
 }