Fix TCP sending

esp. when an imcomplete message is send back from the server.
Fix {A,I}XFR also
Add DNSError

TODO

@@ -14,6 +14,7 @@ Todo:
 
 Issues:
 * Better sized buffers
+* Make the testsuite work with public DNS servers
 * TC bit handling
 * shortened ipv6 addresses are not parsed correctly
 * quoted quotes in txt records

dns.go

@@ -27,6 +27,20 @@ import (
 
 const Year68 = 2 << (32 - 1)
 
+type DNSError struct {
+	Error     string
+	Name      string
+	Server    string
+	IsTimeout bool
+}
+
+func (e *DNSError) String() string {
+        if e == nil {
+                return "<nil>"
+        }
+        return e.Error
+}
+
 type RR interface {
 	Header() *RR_Header
 	String() string

resolver/axfr_test.go

@@ -14,8 +14,8 @@ func TestAXFR(t *testing.T) {
 	res.Servers = []string{"127.0.0.1"}
 	m := new(dns.Msg)
 	m.Question = make([]dns.Question, 1)
-	// ask something
-	m.Question[0] = dns.Question{"miek.nl", dns.TypeAXFR, dns.ClassINET}
+	//m.Question[0] = dns.Question{"miek.nl", dns.TypeAXFR, dns.ClassINET}
+	m.Question[0] = dns.Question{"atoom.net", dns.TypeAXFR, dns.ClassINET}
 
         ch <- DnsMsg{m, nil}
 	for dm := range ch {

resolver/resolver.go

@@ -273,7 +273,7 @@ func exchange_udp(c net.Conn, m []byte, r *Resolver, send bool) (*dns.Msg, os.Er
 // Up to res.Attempts attempts.
 func exchange_tcp(c net.Conn, m []byte, r *Resolver, send bool) (*dns.Msg, os.Error) {
 	var timeout int64
-	var attempts int
+	var attempts, n int
 	if r.Mangle != nil {
 		m = r.Mangle(m)
 	}
@@ -319,16 +319,19 @@ func exchange_tcp(c net.Conn, m []byte, r *Resolver, send bool) (*dns.Msg, os.Er
 		// if length is 0??
 		// And then the message
 		buf := make([]byte, length)
-		_, err = c.Read(buf)
+
+		n, err = c.Read(buf)
 		if err != nil {
-			//println("error reading")
-			//println(err.String())
-			// More Go foo needed
-			//if e, ok := err.(Error); ok && e.Timeout() {
-			//      continue
-			//} 
 			return nil, err
 		}
+		i := n
+		if i < int(length) {
+			n, err = c.Read(buf[i:])
+			if err != nil {
+				return nil, err
+			}
+			i += n
+		}
 		in := new(dns.Msg)
 		if !in.Unpack(buf) {
 			//                        println("unpacking went wrong")