New LogAll variable to enable info and debug error messages

cmd/nbnslistener/nbnslistener.go

@@ -27,6 +27,7 @@ func main() {
 		log.Fatal("invalid CIDR ", err)
 	}
 
+	nbns.LogAll = true
 	handler, err := nbns.NewHandler(*network)
 	if err != nil {
 		log.Fatal("error in nbns", err)

goroutine.go

@@ -62,7 +62,9 @@ func (h *goroutinePool) new(name string) (ret *goroutinePool) {
 func (h *goroutinePool) Begin(name string) *goroutine {
 	g := goroutine{name: name, pool: h}
 	atomic.AddInt32(&h.n, 1)
-	log.Infof("%s goroutine started", g.name)
+	if LogAll {
+		log.Infof("%s goroutine started", g.name)
+	}
 	return &g
 }
 
@@ -76,7 +78,9 @@ func (h *goroutinePool) Stopping() bool {
 func (g *goroutine) End() {
 	atomic.AddInt32(&g.pool.n, -1)
 	stopping := atomic.LoadInt32(&g.pool.stopping)
-	log.Infof("%s goroutine finished - remaining %d", g.name, atomic.LoadInt32(&g.pool.n))
+	if LogAll {
+		log.Infof("%s goroutine finished - remaining %d", g.name, atomic.LoadInt32(&g.pool.n))
+	}
 	if stopping != 0 {
 		g.pool.stoppedChannel <- g
 	}

nbns.go

@@ -16,6 +16,10 @@ type Handler struct {
 	notification  chan<- Entry
 }
 
+// LogAll tells the package to log Info and lower messages
+// Default is to log only Error and Warning; set it to true to log other messages
+var LogAll bool
+
 // Entry holds a NBNS name entry
 type Entry struct {
 	IP   net.IP
@@ -107,7 +111,9 @@ func (h *Handler) ListenAndServe(interval time.Duration) error {
 
 		if err != nil {
 			if err, ok := err.(net.Error); ok && err.Timeout() {
-				log.Debug("NBNS timeout reading result", err)
+				if LogAll {
+					log.Debug("NBNS timeout reading result", err)
+				}
 				continue
 			}
 
@@ -117,12 +123,16 @@ func (h *Handler) ListenAndServe(interval time.Duration) error {
 				if t.Op == "dial" {
 					log.Error("NBNS error unknown host", err)
 				} else if t.Op == "read" {
-					log.Debug("NBNS error conn refused", err)
+					if LogAll {
+						log.Debug("NBNS error conn refused", err)
+					}
 				}
 
 			case syscall.Errno:
 				if t == syscall.ECONNREFUSED {
-					log.Debug("NBNS error connection refused", err)
+					if LogAll {
+						log.Debug("NBNS error connection refused", err)
+					}
 				}
 
 			default:
@@ -135,26 +145,36 @@ func (h *Handler) ListenAndServe(interval time.Duration) error {
 		packet := packet(readBuffer)
 		switch {
 		case packet.opcode() == opcodeQuery && packet.response() == 1:
-			log.Info("nbns received nbns nodeStatusResponse from IP ", *udpAddr)
+			if LogAll {
+				log.Info("nbns received nbns nodeStatusResponse from IP ", *udpAddr)
+			}
 			entry, err := parseNodeStatusResponsePacket(packet, udpAddr.IP)
 			if err != nil {
 				log.Error("error processing nodeStatusResponse ", err)
 				return err
 			}
 
 			if h.notification != nil {
-				log.Debugf("nbns send notification name %s ip %s", entry.Name, entry.IP)
+				if LogAll {
+					if LogAll {
+						log.Debugf("nbns send notification name %s ip %s", entry.Name, entry.IP)
+					}
+				}
 				h.notification <- entry
 			}
 
 		case packet.response() == 0:
 			if packet.trnID() != sequence { // ignore our own request
-				log.Info("nbns not implemented - recvd nbns request from IP ", *udpAddr)
+				if LogAll {
+					log.Info("nbns not implemented - recvd nbns request from IP ", *udpAddr)
+				}
 				packet.printHeader()
 			}
 
 		default:
-			log.Infof("nbns not implemented opcode=%v ", packet.opcode())
+			if LogAll {
+				log.Infof("nbns not implemented opcode=%v ", packet.opcode())
+			}
 			packet.printHeader()
 		}
 

packet.go

@@ -87,7 +87,9 @@ func encodeNBNSName(name string) string {
 	// Final name - len 0x00 means no more names
 	buffer.Write([]byte{0x00})
 
-	log.Debugf("NBNS netbios len %v name ->%s\n", len(buffer.Bytes()), string(buffer.Bytes()))
+	if LogAll {
+		log.Debugf("NBNS netbios len %v name ->%s\n", len(buffer.Bytes()), string(buffer.Bytes()))
+	}
 
 	return string(buffer.Bytes())
 }
@@ -157,16 +159,18 @@ func (p packet) arCount() uint16 { return uint16(p[10])<<8 | uint16(p[11]) }
 func (p packet) payload() []byte { return p[12:] }
 
 func (p packet) printHeader() {
-	fmt.Println("NBNS packet structure")
-	// fmt.Printf("Buffer: 0x%02q\n", p)
-	fmt.Printf("TrnId 0x%04x\n", p.trnID())
-	fmt.Printf("response %b\n", p.response())
-	fmt.Printf("opcode %b\n", p.opcode())
-	fmt.Printf("flags %016b\n", p.flags())
-	fmt.Printf("  broadcast %v\n", p.flagsBroadcast())
-	fmt.Printf("rcode %b\n", p.rcode())
-	fmt.Printf("QDCount 0x%04x | ANCount 0x%04x\n", p.qdCount(), p.anCount())
-	fmt.Printf("NSCount 0x%04x | ARCount 0x%04x\n", p.nsCount(), p.arCount())
+	if LogAll {
+		fmt.Println("NBNS packet structure")
+		// fmt.Printf("Buffer: 0x%02q\n", p)
+		fmt.Printf("TrnId 0x%04x\n", p.trnID())
+		fmt.Printf("response %b\n", p.response())
+		fmt.Printf("opcode %b\n", p.opcode())
+		fmt.Printf("flags %016b\n", p.flags())
+		fmt.Printf("  broadcast %v\n", p.flagsBroadcast())
+		fmt.Printf("rcode %b\n", p.rcode())
+		fmt.Printf("QDCount 0x%04x | ANCount 0x%04x\n", p.qdCount(), p.anCount())
+		fmt.Printf("NSCount 0x%04x | ARCount 0x%04x\n", p.nsCount(), p.arCount())
+	}
 }
 
 // nameQueryWireFormat Name Query Request
@@ -238,7 +242,9 @@ func query(name string, questionType uint16) (packet packet) {
 //   /                           STATISTICS      (variable len)      /
 //   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 func parseNodeStatusResponsePacket(packet packet, ip net.IP) (entry Entry, err error) {
-	log.Debug("nbns parsing node status response packet")
+	if LogAll {
+		log.Debug("nbns parsing node status response packet")
+	}
 
 	// Assume no questions
 	if packet.qdCount() > 0 {
@@ -253,7 +259,9 @@ func parseNodeStatusResponsePacket(packet packet, ip net.IP) (entry Entry, err e
 	// variable len reading
 	buf := bytes.NewBuffer(packet.payload())
 	name := decodeNBNSName(buf)
-	log.Debugf("nbns name: |%s|\n", name)
+	if LogAll {
+		log.Debugf("nbns name: |%s|\n", name)
+	}
 
 	var tmp16 uint16
 	var numNames uint8
@@ -279,8 +287,10 @@ func parseNodeStatusResponsePacket(packet packet, ip net.IP) (entry Entry, err e
 	}
 
 	entry = Entry{IP: ip, Name: table[0]} // first entry
-	log.Debugf("nbns new entry name %s ip %s", entry.Name, entry.IP)
-	log.Debug("nbns node names ", table)
+	if LogAll {
+		log.Debugf("nbns new entry name %s ip %s", entry.Name, entry.IP)
+		log.Debug("nbns node names ", table)
+	}
 
 	return entry, nil
 }