tryDial timeout (#881)

* Change tryDial to handle timeout correctly

* fasthttpproxy/http.go accepts timeout

* Fix example doc

Co-authored-by: Erik Dubbelboer <erik@dubbelboer.com>

* Improve import in httpproxy

* Simplify tryDial

* Cleanup

* Wait for concurrencyCh

Co-authored-by: Erik Dubbelboer <erik@dubbelboer.com>

1 files changed, 7 insertions, 36 deletions

diff --git a/tcpdialer.go b/tcpdialer.go
index b51bb21..8d6bbfb 100644
--- a/tcpdialer.go
+++ b/tcpdialer.go
@@ -324,48 +324,19 @@ func (d *TCPDialer) tryDial(network string, addr *net.TCPAddr, deadline time.Tim
 				return nil, ErrDialTimeout
 			}
 		}
+		defer func() { <-concurrencyCh }()
 	}
 
-	chv := dialResultChanPool.Get()
-	if chv == nil {
-		chv = make(chan dialResult, 1)
-	}
-	ch := chv.(chan dialResult)
-	go func() {
-		var dr dialResult
-		dr.conn, dr.err = net.DialTCP(network, d.LocalAddr, addr)
-		ch <- dr
-		if concurrencyCh != nil {
-			<-concurrencyCh
-		}
-	}()
-
-	var (
-		conn net.Conn
-		err  error
-	)
-
-	tc := AcquireTimer(timeout)
-	select {
-	case dr := <-ch:
-		conn = dr.conn
-		err = dr.err
-		dialResultChanPool.Put(ch)
-	case <-tc.C:
-		err = ErrDialTimeout
+	dialer := net.Dialer{LocalAddr: d.LocalAddr}
+	ctx, cancel_ctx := context.WithDeadline(context.Background(), deadline)
+	defer cancel_ctx()
+	conn, err := dialer.DialContext(ctx, network, addr.String())
+	if err != nil && ctx.Err() == context.DeadlineExceeded {
+		return nil, ErrDialTimeout
 	}
-	ReleaseTimer(tc)
-
 	return conn, err
 }
 
-var dialResultChanPool sync.Pool
-
-type dialResult struct {
-	conn net.Conn
-	err  error
-}
-
 // ErrDialTimeout is returned when TCP dialing is timed out.
 var ErrDialTimeout = errors.New("dialing to the given TCP address timed out")