From da9f1a80139977cca88e01c5a2fd665ea3df48d2 Mon Sep 17 00:00:00 2001
From: Darien Raymond <admin@v2ray.com>
Date: Tue, 11 Oct 2016 12:30:53 +0200
Subject: [PATCH] predicate.Not

---
 common/predicate/predicate.go        |  6 ++++++
 transport/internet/kcp/connection.go | 16 ++++++++++------
 2 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/common/predicate/predicate.go b/common/predicate/predicate.go
index d107071f..d5a9016d 100644
--- a/common/predicate/predicate.go
+++ b/common/predicate/predicate.go
@@ -23,3 +23,9 @@ func Any(predicates ...Predicate) Predicate {
 		return false
 	}
 }
+
+func Not(predicate Predicate) Predicate {
+	return func() bool {
+		return !predicate()
+	}
+}
diff --git a/transport/internet/kcp/connection.go b/transport/internet/kcp/connection.go
index 7b3ad43b..eba9feb9 100644
--- a/transport/internet/kcp/connection.go
+++ b/transport/internet/kcp/connection.go
@@ -225,17 +225,21 @@ func NewConnection(conv uint16, writerCloser io.WriteCloser, local *net.UDPAddr,
 	conn.congestionControl = config.Congestion
 	conn.sendingWorker = NewSendingWorker(conn)
 
+	isTerminating := func() bool {
+		return conn.State().Is(StateTerminating, StateTerminated)
+	}
+	isTerminated := func() bool {
+		return conn.State() == StateTerminated
+	}
 	conn.dataUpdater = NewUpdater(
 		conn.interval,
-		predicate.Any(conn.sendingWorker.UpdateNecessary, conn.receivingWorker.UpdateNecessary),
-		func() bool {
-			return conn.State() == StateTerminated
-		},
+		predicate.All(predicate.Not(isTerminating), predicate.Any(conn.sendingWorker.UpdateNecessary, conn.receivingWorker.UpdateNecessary)),
+		isTerminating,
 		conn.updateTask)
 	conn.pingUpdater = NewUpdater(
 		5000, // 5 seconds
-		func() bool { return conn.State() != StateTerminated },
-		func() bool { return conn.State() == StateTerminated },
+		predicate.Not(isTerminated),
+		isTerminated,
 		conn.updateTask)
 	conn.pingUpdater.WakeUp()