split into small files

grace/listener.go

@@ -0,0 +1,62 @@
+package grace
+
+import (
+	"net"
+	"os"
+	"syscall"
+	"time"
+)
+
+type graceListener struct {
+	net.Listener
+	stop    chan error
+	stopped bool
+	server  *graceServer
+}
+
+func newGraceListener(l net.Listener, srv *graceServer) (el *graceListener) {
+	el = &graceListener{
+		Listener: l,
+		stop:     make(chan error),
+		server:   srv,
+	}
+	go func() {
+		_ = <-el.stop
+		el.stopped = true
+		el.stop <- el.Listener.Close()
+	}()
+	return
+}
+
+func (gl *graceListener) Accept() (c net.Conn, err error) {
+	tc, err := gl.Listener.(*net.TCPListener).AcceptTCP()
+	if err != nil {
+		return
+	}
+
+	tc.SetKeepAlive(true)
+	tc.SetKeepAlivePeriod(3 * time.Minute)
+
+	c = graceConn{
+		Conn:   tc,
+		server: gl.server,
+	}
+
+	gl.server.wg.Add(1)
+	return
+}
+
+func (el *graceListener) Close() error {
+	if el.stopped {
+		return syscall.EINVAL
+	}
+	el.stop <- nil
+	return <-el.stop
+}
+
+func (el *graceListener) File() *os.File {
+	// returns a dup(2) - FD_CLOEXEC flag *not* set
+	tl := el.Listener.(*net.TCPListener)
+	fl, _ := tl.File()
+	return fl
+}