1 files changed, 10 insertions, 22 deletions
diff --git a/rrdformat/marshal_xml.go b/rrdformat/marshal_xml.go
index 7b97894..cb2db93 100644
--- a/rrdformat/marshal_xml.go
+++ b/rrdformat/marshal_xml.go
@@ -3,6 +3,8 @@ package rrdformat
 import (
 	"encoding/xml"
 	"strconv"
+
+	"git.lukeshu.com/go/librrd/rrdformat/rrdbinary"
 )
 
 //const XMLNS = "https://oss.oetiker.ch/rrdtool/rrdtool-dump.xml"
@@ -50,7 +52,7 @@ func (rrd RRD) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
 	}
 	// 3. Data Sources
 	for _, ds := range rrd.DSDefs {
-		if err := e.EncodeElement(ds, xmlStart("ds")); err != nil {
+		if err := ds.marshalXML(rrd, e, xmlStart("ds")); err != nil {
 			return err
 		}
 	}
@@ -87,7 +89,7 @@ func (t TimeWithUsec) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
 	return nil
 }
 
-func (ds DSDef) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
+func (ds DSDef) marshalXML(rrd RRD, e *xml.Encoder, start xml.StartElement) error {
 	if err := e.EncodeToken(start); err != nil {
 		return err
 	}
@@ -101,29 +103,14 @@ func (ds DSDef) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
 	switch ds.DSType {
 	case DST_CDEF:
 		var rpnps []rrdbinary.RPNToken
-		for _, param := range ds.Params {
+		for _, param := range ds.Parameters {
 			rpnps = append(rpnps, param.AsRPNTokens()...)
 		}
-		strs := make([]string, len(rpnps))
-		for _, rpnp := range rpnps {
-			switch Op(rpnp.Op) {
-			case OP_NUMBER:
-				strs = append(strs, fmt.Sprintf("%d", rpnp.Val))
-			case OP_VARIABLE:
-				if rpnp.Val < 0 || rpnp.Val >= len(rrd.DSDefs) {
-					return fmt.Errorf("out-of-bounds %s %d", Op(rpnp.Op), rpnp.Val)
-				}
-				strs = append(strs, rrd.DSDefs[int(rpnp.Val)].Name)
-			case OP_PREV_OTHER:
-				if rpnp.Val < 0 || rpnp.Val >= len(rrd.DSDefs) {
-					return fmt.Errorf("out-of-bounds %s %d", Op(rpnp.Op), rpnp.Val)
-				}
-				strs = append(strs, fmt.Sprintf("PREV(%s)", rrd.DSDefs[int(rpnp.Val)].Name))
-			default:
-				strs = append(strs, rpnp.Op.String())
-			}
+		str, err := rrd.RPNCompactToString(rpnps)
+		if err != nil {
+			return err
 		}
-		if err := e.EncodeElement(strings.Join(strs, ","), xmlStart("cdef")); err != nil {
+		if err := e.EncodeElement(str, xmlStart("cdef")); err != nil {
 			return err
 		}
 	default:
@@ -133,4 +120,5 @@ func (ds DSDef) MarshalXML(e *xml.Encoder, start xml.StartElement) error {
 	if err := e.EncodeToken(start.End()); err != nil {
 		return err
 	}
+	return nil
 }