[mx] more error nitpicks

1 files changed, 16 insertions, 12 deletions

diff --git a/memex/sdar.go b/memex/sdar.go
index ac4666b..dc3a6a9 100644
--- a/memex/sdar.go
+++ b/memex/sdar.go
@@ -45,9 +45,9 @@ type SdarReader struct{ *SdarProcess }
 var SdarPath string
 
 var (
-	readError  = errors.New("sdar read failed")
-	addError   = errors.New("sdar add failed")
-	protoError = errors.New("sdar protocol error")
+	readError  = errors.New("read failed")
+	addError   = errors.New("add failed")
+	protoError = errors.New("protocol error")
 )
 
 func (a Addr) Ok() bool {
@@ -282,30 +282,34 @@ func (a SdarAdder) AddBuffer(b *bytes.Buffer) (Addr, error) {
 	return a.getAddr()
 }
 
-func (r SdarReader) writeStreamTo(limit int, w io.Writer) error {
+func (r SdarReader) writeStreamTo(limit int, w io.Writer, addr Addr) error {
 	for {
 		ans := readPkt(r.output)
 		if len(ans) < 3 {
 			return r.err(protoError)
 		}
+		wrap := func(e error) error {
+			short := addr.String()[:10] + "..."
+			return r.err(fmt.Errorf("%w for %s", e, short))
+		}
 		switch string(ans[:3]) {
 		default:
-			return r.err(protoError)
+			return wrap(protoError)
 		case "err":
-			return r.err(readError)
+			return wrap(readError)
 		case "end":
 			return nil
 		case "raw":
 			if len(ans) < 4 || ans[3] != ' ' {
-				return r.err(protoError)
+				return wrap(protoError)
 			}
 			nb, err := strconv.Atoi(string(ans[4 : len(ans)-1]))
 			if err != nil || (limit >= 0 && nb > limit) {
-				return r.err(protoError)
+				return wrap(protoError)
 			}
 			n, err := io.CopyN(w, r.output, int64(nb))
 			if int(n) != nb || err != nil {
-				return r.err(protoError)
+				return wrap(protoError)
 			}
 			if limit >= 0 {
 				limit -= int(n)
@@ -318,7 +322,7 @@ func (r SdarReader) WriteTo(addr Addr, w io.Writer) error {
 	if err := r.sendPkt("%v", addr); err != nil {
 		return err
 	}
-	return r.writeStreamTo(-1, w)
+	return r.writeStreamTo(-1, w, addr)
 }
 
 func (r SdarReader) ReadObject(b []byte, addr Addr, off int64) (int, error) {
@@ -329,7 +333,7 @@ func (r SdarReader) ReadObject(b []byte, addr Addr, off int64) (int, error) {
 		return 0, err
 	}
 	buf := bytes.NewBuffer(b[:0])
-	err := r.writeStreamTo(len(b), buf)
+	err := r.writeStreamTo(len(b), buf, addr)
 	return buf.Len(), err
 }
 
@@ -341,7 +345,7 @@ func (r SdarReader) ReadAll(addr Addr) (*bytes.Buffer, error) {
 		return nil, err
 	}
 	var buf bytes.Buffer
-	err := r.writeStreamTo(-1, &buf)
+	err := r.writeStreamTo(-1, &buf, addr)
 	return &buf, err
 }