From dceb8ee535dafbc56740c7ab702e067c9ea8ecce Mon Sep 17 00:00:00 2001
From: wwqgtxx <wwqgtxx@gmail.com>
Date: Wed, 13 Mar 2024 14:49:46 +0800
Subject: [PATCH] fix: resolve atomic.Value usages with interface types

---
 common/atomic/value.go | 19 +++++++++++++++----
 go.mod                 |  2 +-
 go.sum                 |  4 ++--
 3 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/common/atomic/value.go b/common/atomic/value.go
index cbc6c5b8c..36623b3ee 100644
--- a/common/atomic/value.go
+++ b/common/atomic/value.go
@@ -15,20 +15,31 @@ type TypedValue[T any] struct {
 	value atomic.Value
 }
 
+// tValue is a struct with determined type to resolve atomic.Value usages with interface types
+// https://github.com/golang/go/issues/22550
+//
+// The intention to have an atomic value store for errors. However, running this code panics:
+// panic: sync/atomic: store of inconsistently typed value into Value
+// This is because atomic.Value requires that the underlying concrete type be the same (which is a reasonable expectation for its implementation).
+// When going through the atomic.Value.Store method call, the fact that both these are of the error interface is lost.
+type tValue[T any] struct {
+	value T
+}
+
 func (t *TypedValue[T]) Load() T {
 	value := t.value.Load()
 	if value == nil {
 		return DefaultValue[T]()
 	}
-	return value.(T)
+	return value.(tValue[T]).value
 }
 
 func (t *TypedValue[T]) Store(value T) {
-	t.value.Store(value)
+	t.value.Store(tValue[T]{value})
 }
 
 func (t *TypedValue[T]) Swap(new T) T {
-	old := t.value.Swap(new)
+	old := t.value.Swap(tValue[T]{new})
 	if old == nil {
 		return DefaultValue[T]()
 	}
@@ -36,7 +47,7 @@ func (t *TypedValue[T]) Swap(new T) T {
 }
 
 func (t *TypedValue[T]) CompareAndSwap(old, new T) bool {
-	return t.value.CompareAndSwap(old, new)
+	return t.value.CompareAndSwap(tValue[T]{old}, tValue[T]{new})
 }
 
 func (t *TypedValue[T]) MarshalJSON() ([]byte, error) {
diff --git a/go.mod b/go.mod
index 2d1ac543e..9becc8c85 100644
--- a/go.mod
+++ b/go.mod
@@ -111,4 +111,4 @@ require (
 	golang.org/x/tools v0.18.0 // indirect
 )
 
-replace github.com/sagernet/sing => github.com/metacubex/sing v0.0.0-20240313005020-c77f32e55220
+replace github.com/sagernet/sing => github.com/metacubex/sing v0.0.0-20240313064558-c197257f6542
diff --git a/go.sum b/go.sum
index 62e8fb69b..7277a32e1 100644
--- a/go.sum
+++ b/go.sum
@@ -106,8 +106,8 @@ github.com/metacubex/gvisor v0.0.0-20240214095142-666a73bcf165 h1:QIQI4gEm+gTwVN
 github.com/metacubex/gvisor v0.0.0-20240214095142-666a73bcf165/go.mod h1:SKY70wiF1UTSoyuDZyKPMsUC6MsMxh8Y3ZNkIa6J3fU=
 github.com/metacubex/quic-go v0.41.1-0.20240307164142-46c6f7cdf2d1 h1:63zKmEWU4MB5MjUSCmeDhm3OzilF7ypXWPq0gAA2GE8=
 github.com/metacubex/quic-go v0.41.1-0.20240307164142-46c6f7cdf2d1/go.mod h1:F/t8VnA47xoia8ABlNA4InkZjssvFJ5p6E6jKdbkgAs=
-github.com/metacubex/sing v0.0.0-20240313005020-c77f32e55220 h1:lZLFR28Jf3gjoHh560uC8AKnWcQ2+VQoQY/rSj6kSrc=
-github.com/metacubex/sing v0.0.0-20240313005020-c77f32e55220/go.mod h1:+60H3Cm91RnL9dpVGWDPHt0zTQImO9Vfqt9a4rSambI=
+github.com/metacubex/sing v0.0.0-20240313064558-c197257f6542 h1:e9nBnrJBv3HzZVeSzJN0G2SADjebd2ZLF1F5dmsjUTc=
+github.com/metacubex/sing v0.0.0-20240313064558-c197257f6542/go.mod h1:+60H3Cm91RnL9dpVGWDPHt0zTQImO9Vfqt9a4rSambI=
 github.com/metacubex/sing-quic v0.0.0-20240310154810-47bca850fc01 h1:5INHs85Gp1JZsdF7fQp1pXUjfJOX2dhwZjuUQWJVSt8=
 github.com/metacubex/sing-quic v0.0.0-20240310154810-47bca850fc01/go.mod h1:WyY0zYxv+o+18R/Ece+QFontlgXoobKbNqbtYn2zjz8=
 github.com/metacubex/sing-shadowsocks v0.2.6 h1:6oEB3QcsFYnNiFeoevcXrCwJ3sAablwVSgtE9R3QeFQ=