From 90200fbecb45e098209ff7c1f45d03ea0ecde8bf Mon Sep 17 00:00:00 2001
From: Darien Raymond <admin@v2ray.com>
Date: Mon, 13 Feb 2017 23:12:27 +0100
Subject: [PATCH] remove signal.Once

---
 common/signal/once.go               | 29 -----------------------------
 transport/internet/internal/pool.go | 23 ++++++++++++++---------
 2 files changed, 14 insertions(+), 38 deletions(-)
 delete mode 100644 common/signal/once.go

diff --git a/common/signal/once.go b/common/signal/once.go
deleted file mode 100644
index db30b009..00000000
--- a/common/signal/once.go
+++ /dev/null
@@ -1,29 +0,0 @@
-package signal
-
-import (
-	"sync"
-	"sync/atomic"
-)
-
-type Once struct {
-	m    sync.Mutex
-	done uint32
-}
-
-func (o *Once) Do(f func()) {
-	if atomic.LoadUint32(&o.done) == 1 {
-		return
-	}
-	o.m.Lock()
-	defer o.m.Unlock()
-	if o.done == 0 {
-		atomic.StoreUint32(&o.done, 1)
-		f()
-	}
-}
-
-func (o *Once) Reset() {
-	o.m.Lock()
-	defer o.m.Unlock()
-	atomic.StoreUint32(&o.done, 0)
-}
diff --git a/transport/internet/internal/pool.go b/transport/internet/internal/pool.go
index fe8b8371..efa87724 100644
--- a/transport/internet/internal/pool.go
+++ b/transport/internet/internal/pool.go
@@ -4,8 +4,6 @@ import (
 	"net"
 	"sync"
 	"time"
-
-	"v2ray.com/core/common/signal"
 )
 
 // ConnectionRecyler is the interface for recycling connections.
@@ -32,15 +30,18 @@ func (ec *ExpiringConnection) Expired() bool {
 // Pool is a connection pool.
 type Pool struct {
 	sync.Mutex
-	connsByDest map[ConnectionID][]*ExpiringConnection
-	cleanupOnce signal.Once
+	connsByDest  map[ConnectionID][]*ExpiringConnection
+	cleanupToken chan bool
 }
 
 // NewConnectionPool creates a new Pool.
 func NewConnectionPool() *Pool {
-	return &Pool{
-		connsByDest: make(map[ConnectionID][]*ExpiringConnection),
+	p := &Pool{
+		connsByDest:  make(map[ConnectionID][]*ExpiringConnection),
+		cleanupToken: make(chan bool, 1),
 	}
+	p.cleanupToken <- true
+	return p
 }
 
 // Get returns a connection with matching connection ID. Nil if not found.
@@ -73,7 +74,9 @@ func (p *Pool) Get(id ConnectionID) net.Conn {
 }
 
 func (p *Pool) cleanup() {
-	defer p.cleanupOnce.Reset()
+	defer func() {
+		p.cleanupToken <- true
+	}()
 
 	for len(p.connsByDest) > 0 {
 		time.Sleep(time.Second * 5)
@@ -117,7 +120,9 @@ func (p *Pool) Put(id ConnectionID, conn net.Conn) {
 	}
 	p.connsByDest[id] = list
 
-	p.cleanupOnce.Do(func() {
+	select {
+	case <-p.cleanupToken:
 		go p.cleanup()
-	})
+	default:
+	}
 }