Golang InitQueryChannels Examples

Example #1

File: xfrprx.go Project: elazarl/godns

func main() {
	err := make(chan os.Error)

	// Outgoing queries
	dns.InitQueryChannels()
	go query("tcp", err)
	go query("udp", err)

	// Incoming queries
	go listen("tcp", "127.0.0.1:8053", err)
	go listen("tcp", "[::1]:8053", err)
	go listen("udp", "127.0.0.1:8053", err)
	go listen("udp", "[::1]:8053", err)

forever:
	for {
		select {
		case e := <-err:
			fmt.Printf("Error received, stopping: %s\n", e.String())
			break forever
		case <-signal.Incoming:
			fmt.Printf("Signal received, stopping\n")
			break forever
		case q := <-dns.QueryReply:
			fmt.Printf("Query received:\n%v\n", q.Reply)
		}
	}
	close(err)
}

Example #2

File: q.go Project: elazarl/godns

func main() {
	var dnssec *bool = flag.Bool("dnssec", false, "Request DNSSEC records")
	var short *bool = flag.Bool("short", false, "Abbriate long DNSKEY and RRSIG RRs")
	var aa *bool = flag.Bool("aa", false, "Set AA flag in query")
	var ad *bool = flag.Bool("ad", false, "Set AD flag in query")
	var cd *bool = flag.Bool("cd", false, "Set CD flag in query")
	var rd *bool = flag.Bool("rd", true, "Unset RD flag in query")
	var tcp *bool = flag.Bool("tcp", false, "TCP mode")
	var nsid *bool = flag.Bool("nsid", false, "Ask for the NSID")
	flag.Usage = func() {
		fmt.Fprintf(os.Stderr, "Usage: %s [@server(:port)] [qtype] [qclass] [name ...]\n", os.Args[0])
		flag.PrintDefaults()
	}

	// Need to think about it... Config
	c, _ := dns.ClientConfigFromFile("/etc/resolv.conf")
	nameserver := "@" + c.Servers[0]
	qtype := uint16(dns.TypeA)      // Default qtype
	qclass := uint16(dns.ClassINET) // Default qclass
	var qname []string

	flag.Parse()

Flags:
	for i := 0; i < flag.NArg(); i++ {
		// If it starts with @ it is a nameserver
		if flag.Arg(i)[0] == '@' {
			nameserver = flag.Arg(i)
			continue Flags
		}
		// First class, then type, to make ANY queries possible
		// And if it looks like type, it is a type
		for k, v := range dns.Rr_str {
			if v == strings.ToUpper(flag.Arg(i)) {
				qtype = k
				continue Flags
			}
		}
		// If it looks like a class, it is a class
		for k, v := range dns.Class_str {
			if v == strings.ToUpper(flag.Arg(i)) {
				qclass = k
				continue Flags
			}
		}
		// If it starts with TYPExxx it is unknown rr
		if strings.HasPrefix(flag.Arg(i), "TYPE") {
			i, e := strconv.Atoi(string([]byte(flag.Arg(i))[4:]))
			if e == nil {
				qtype = uint16(i)
				continue Flags
			}
		}

		// Anything else is a qname
		qname = append(qname, flag.Arg(i))
	}

	nameserver = string([]byte(nameserver)[1:]) // chop off @
	if !strings.HasSuffix(nameserver, ":53") {
		nameserver += ":53"
	}

	err := make(chan os.Error)
	if *tcp {
		go query("tcp", err)
	} else {
		go query("udp", err)
	}

	dns.InitQueryChannels()
	// Start the querier in a closure
	go func() {
		for _, v := range qname {
			d, m := newConnMsg(v, nameserver, c.Attempts, qtype, qclass, *aa, *ad, *cd, *rd, *dnssec, *nsid)
			dns.QueryRequest <- &dns.Query{Query: m, Conn: d}
		}
	}()

	i := 0
forever:
	for {
		select {
		case r := <-dns.QueryReply:
			if r.Reply != nil {
				if r.Query.Id != r.Reply.Id {
					fmt.Printf("Id mismatch\n")
				}
				if *short {
					r.Reply = shortMsg(r.Reply)
				}
				fmt.Printf("%v", r.Reply)
			} else {
				fmt.Printf("%v\n", r.Err.String())
			}
			i++
			if i == len(qname) {
				break forever
			}
		case e := <-err:
			fmt.Printf("%v", e.String())
			break forever
		}
	}
}