From cc407796cd93d765edb57bd687afeec70920f522 Mon Sep 17 00:00:00 2001
From: Kirill Danshin <kirill@danshin.pro>
Date: Thu, 16 Apr 2020 22:47:01 +0300
Subject: [PATCH] fix: s.concurrency stays 0 when you don't use s.ServeConn

Signed-off-by: Kirill Danshin <kirill@danshin.pro>
---
 server.go | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/server.go b/server.go
index 43a4507..34e6f43 100644
--- a/server.go
+++ b/server.go
@@ -1888,8 +1888,14 @@ func (s *Server) idleTimeout() time.Duration {
 	return s.ReadTimeout
 }
 
+func (s *Server) serveConnCleanup() {
+	atomic.AddInt32(&s.open, -1)
+	atomic.AddUint32(&s.concurrency, ^uint32(0))
+}
+
 func (s *Server) serveConn(c net.Conn) (err error) {
-	defer atomic.AddInt32(&s.open, -1)
+	defer s.serveConnCleanup()
+	atomic.AddUint32(&s.concurrency, 1)
 
 	var proto string
 	if proto, err = s.getNextProto(c); err != nil {