doc tweaks, Len() tweaks

dns.go

@@ -19,15 +19,15 @@
 //
 // Or directly from a string:
 //
-//      mx := NewRR("miek.nl. 3600 IN MX 10 mx.miek.nl.")
+//      mx, err := NewRR("miek.nl. 3600 IN MX 10 mx.miek.nl.")
 //
 // Or when the default TTL (3600) and class (IN) suit you:
 //
-//      mx := NewRR("miek.nl. MX 10 mx.miek.nl.")
+//      mx, err := NewRR("miek.nl. MX 10 mx.miek.nl.")
 //
 // Or even:
 //
-//      mx := NewRR("$ORIGIN nl.\nmiek 1H IN MX 10 mx.miek")
+//      mx, err := NewRR("$ORIGIN nl.\nmiek 1H IN MX 10 mx.miek")
 // 
 // The package dns supports (async) querying/replying, incoming/outgoing Axfr/Ixfr, 
 // TSIG, EDNS0, dynamic updates, notifies and DNSSEC validation/signing.

dns_test.go

@@ -101,3 +101,21 @@ func TestBailiwick(t *testing.T) {
 		}
 	}
 }
+
+func TestPack(t *testing.T) {
+	rr := []string{"US.    86400	IN	NSEC	0-.us. NS SOA RRSIG NSEC DNSKEY TYPE65534"}
+	m := new(Msg)
+	var err error
+	m.Answer = make([]RR, 1)
+	for _, r := range rr {
+		m.Answer[0], err = NewRR(r)
+		if err != nil {
+			t.Logf("Failed to create RR: %s\n", err.Error())
+			continue
+		}
+		if _, ok := m.Pack(); !ok {
+			t.Log("Packing failed")
+			t.Fail()
+		}
+	}
+}

msg.go

@@ -1119,6 +1119,9 @@ func (h *MsgHdr) String() string {
 // Pack packs a Msg: it is converted to to wire format.
 // If the dns.Compress is true the message will be in compressed wire format.
 func (dns *Msg) Pack() (msg []byte, ok bool) {
+	if dns == nil {
+		return nil, false
+	}
 	var dh Header
 	compression := make(map[string]int) // Compression pointer mappings
 
@@ -1278,25 +1281,18 @@ func (dns *Msg) String() string {
 func (dns *Msg) Len() int {
 	// Message header is always 12 bytes       
 	l := 12
-	if len(dns.Question) > 0 {
-		for i := 0; i < len(dns.Question); i++ {
-			l += dns.Question[i].Len()
-		}
+	for i := 0; i < len(dns.Question); i++ {
+		l += dns.Question[i].Len()
 	}
-	if len(dns.Answer) > 0 {
-		for i := 0; i < len(dns.Answer); i++ {
-			l += dns.Answer[i].Len()
-		}
+	println("LENGTE", len(dns.Answer))
+	for i := 0; i < len(dns.Answer); i++ {
+		l += dns.Answer[i].Len()
 	}
-	if len(dns.Ns) > 0 {
-		for i := 0; i < len(dns.Ns); i++ {
-			l += dns.Ns[i].Len()
-		}
+	for i := 0; i < len(dns.Ns); i++ {
+		l += dns.Ns[i].Len()
 	}
-	if len(dns.Extra) > 0 {
-		for i := 0; i < len(dns.Extra); i++ {
-			l += dns.Extra[i].Len()
-		}
+	for i := 0; i < len(dns.Extra); i++ {
+		l += dns.Extra[i].Len()
 	}
 	return l
 }