lib9p

commit f1403e4335ed6f975ab98811715b23c205a422c9
parent d56d187be5ac61be68b72c82192bd93a5546b082
Author: Matsuda Kenji <info@mtkn.jp>
Date:   Sat, 15 Jul 2023 10:56:06 +0900

implement error

Diffstat:
M
fcall.go
 | 
30
+++++++++++++++++++++++++++++-
M
server.go
 | 
33
++++++++++++++++++++++++---------

2 files changed, 53 insertions(+), 10 deletions(-)
diff --git a/fcall.go b/fcall.go
@@ -189,7 +189,6 @@ func (msg RVersion) String() string {
 
 type TAuth []byte
 type RAuth []byte
-type RError []byte
 
 type TAttach []byte
 
@@ -238,3 +237,31 @@ func (msg RAttach) String() string {
 	return fmt.Sprintf("Rattach tag %d qid %v",
 		msg.Tag(), msg.Qid())
 }
+
+type RError []byte
+
+func (msg RError) Size() uint32      { return gbit32(msg[0:4]) }
+func (msg RError) SetSize(s uint32)  { pbit32(msg[0:4], s) }
+func (msg RError) Type() MsgType     { return MsgType(msg[4]) }
+func (msg RError) SetType(t MsgType) { msg[4] = byte(t) }
+func (msg RError) Tag() uint16       { return gbit16(msg[5:7]) }
+func (msg RError) SetTag(t uint16)   { pbit16(msg[5:7], t) }
+func (msg RError) conv2M() []byte  { return []byte(msg)[:msg.Size()] }
+func (msg RError) EName() error {
+	size := gbit16(msg[7:9])
+	return fmt.Errorf("%s", string(msg[9:9+size]))
+}
+func (msg RError) SetEName(err error) {
+	size := uint32(len(err.Error()))
+	uint16Max := uint32(1 << 16)
+	if size >= uint16Max {
+		panic("error message too large")
+	}
+	pbit16(msg[7:9], uint16(size))
+	for i := 0; i < int(size); i++ {
+		msg[9+i] = err.Error()[i]
+	}
+}
+func (msg RError) String() string {
+	return fmt.Sprintf("Rerror tag %d ename %v", msg.Tag(), msg.EName())
+}
+\ No newline at end of file
diff --git a/server.go b/server.go
@@ -80,6 +80,18 @@ func sVersion(s *Srv, r *Req) {
 
 func rVersion(r *Req, err error) {}
 
+func rError(r *Req, err error) {
+	size := uint32(4 + 1 + 2 + 2 + len(err.Error()))
+	ofcall := RError(make([]byte, size))
+
+	ofcall.SetSize(size)
+	ofcall.SetType(Rerror)
+	ofcall.SetTag(r.ifcall.Tag())
+	ofcall.SetEName(err)
+
+	r.ofcall = ofcall
+}
+
 func Serve(s *Srv) {
 	for {
 		r, err := getReq(s)
@@ -89,7 +101,7 @@ func Serve(s *Srv) {
 		}
 		switch r.ifcall.Type() {
 		default:
-			log.Print("unknown message type")
+			respond(r, fmt.Errorf("unknown message type: %d", r.ifcall.Type()))
 		case Tversion:
 			sVersion(s, r)
 		}
@@ -97,12 +109,16 @@ func Serve(s *Srv) {
 }
 
 func respond(r *Req, err error) {
-	switch ofcall := r.ofcall.(type) {
-	default:
-		// TODO: Respond with Rerror.
-		log.Fatalf("unknown message type: %v", ofcall)
-	case RVersion:
-		rVersion(r, err)
+	if err != nil {
+		rError(r, err)
+	} else {
+		switch ofcall := r.ofcall.(type) {
+		default:
+			// TODO: Respond with Rerror.
+			rError(r, fmt.Errorf("unknown message type: %s", ofcall.Type()))
+		case RVersion:
+			rVersion(r, err)
+		}
 	}
 
 	if chatty9P {
@@ -110,4 +126,4 @@ func respond(r *Req, err error) {
 	}
 	r.srv.Write(r.ofcall.conv2M())
 
-}
-\ No newline at end of file
+}