design: def protocol stack

protocol_stack.go

@@ -0,0 +1,45 @@
+package nbio
+
+import (
+	"net"
+)
+
+type Protocol interface {
+	Parse(c net.Conn, b []byte, ps *ProtocolStack) (net.Conn, []byte, error)
+	Write(b []byte) (int, error)
+}
+
+type ProtocolStack struct {
+	stack []Protocol
+}
+
+func (ps *ProtocolStack) Add(p Protocol) {
+	ps.stack = append(ps.stack, p)
+}
+
+func (ps *ProtocolStack) Delete(p Protocol) {
+	for i, v := range ps.stack {
+		if v == p {
+			ps.stack[i] = nil
+			return
+		}
+	}
+}
+
+func (ps *ProtocolStack) Parse(c net.Conn, b []byte, ps_ ProtocolStack) (net.Conn, []byte, error) {
+	var err error
+	for _, p := range ps.stack {
+		if p == nil {
+			continue
+		}
+		c, b, err = p.Parse(c, b, ps)
+		if err != nil {
+			break
+		}
+	}
+	return c, b, err
+}
+
+func (ps *ProtocolStack) Write(b []byte) (int, error) {
+	return -1, ErrUnsupported
+}