feat: impl. new protol design & new head

gold/proto/hello.go

@@ -0,0 +1,30 @@
+package proto
+
+import (
+	"github.com/fumiama/orbyte/pbuf"
+	"github.com/sirupsen/logrus"
+
+	"github.com/fumiama/WireGold/gold/head"
+	"github.com/fumiama/WireGold/gold/link"
+	"github.com/fumiama/WireGold/internal/file"
+)
+
+func init() {
+	link.AddProto(head.ProtoHello, func(_ *head.Packet, peer *link.Link, data pbuf.Bytes) {
+		onHello(data, peer)
+	})
+}
+
+func onHello(data pbuf.Bytes, p *link.Link) {
+	data.V(func(b []byte) {
+		switch {
+		case len(b) == 0:
+			logrus.Warnln(file.Header(), "recv old packet, do nothing")
+		case b[0] == byte(head.HelloPing):
+			go p.WritePacket(head.ProtoHello, []byte{byte(head.HelloPong)})
+			logrus.Infoln(file.Header(), "recv, send ack")
+		default:
+			logrus.Infoln(file.Header(), "recv ack, do nothing")
+		}
+	})
+}