func sendPing(conn *net.IPConn, addr *net.IPAddr, id, seq int) {
bytes, err := (&icmpMessage{
Type: icmpv4EchoRequest, Code: 0,
Body: &icmpEcho{
ID: id, Seq: seq,
Data: timeToBytes(time.Now()),
},
}).Marshal()
if err != nil {
panic(err)
}
for {
if _, _, err := conn.WriteMsgIP(bytes, nil, addr); err != nil {
if neterr, ok := err.(*net.OpError); ok {
if neterr.Err == syscall.ENOBUFS {
// creating a busy loop?
continue
}
}
}
fmt.Printf("ICMP: Ping sent: %s, id=%d.\n", addr.String(), id)
break
}
}
func (p *Pinger) sendICMP(conn, conn6 *net.IPConn) (map[string]*net.IPAddr, error) {
p.debugln("sendICMP(): Start")
p.mu.Lock()
p.id = rand.Intn(0xffff)
p.seq = rand.Intn(0xffff)
p.mu.Unlock()
queue := make(map[string]*net.IPAddr)
wg := new(sync.WaitGroup)
for key, addr := range p.addrs {
var typ int
var cn *net.IPConn
if isIPv4(addr.IP) {
typ = icmpv4EchoRequest
cn = conn
} else if isIPv6(addr.IP) {
typ = icmpv6EchoRequest
cn = conn6
} else {
continue
}
if cn == nil {
continue
}
t := timeToBytes(time.Now())
if p.Size-TimeSliceLength != 0 {
t = append(t, byteSliceOfSize(p.Size-TimeSliceLength)...)
}
p.mu.Lock()
bytes, err := (&icmpMessage{
Type: typ, Code: 0,
Body: &icmpEcho{
ID: p.id, Seq: p.seq,
Data: t,
},
}).Marshal()
p.mu.Unlock()
if err != nil {
wg.Wait()
return queue, err
}
queue[key] = addr
p.debugln("sendICMP(): Invoke goroutine")
wg.Add(1)
go func(conn *net.IPConn, ra *net.IPAddr, b []byte) {
for {
if _, _, err := conn.WriteMsgIP(bytes, nil, ra); err != nil {
if neterr, ok := err.(*net.OpError); ok {
if neterr.Err == syscall.ENOBUFS {
continue
}
}
}
break
}
p.debugln("sendICMP(): WriteMsgIP End")
wg.Done()
}(cn, addr, bytes)
}
wg.Wait()
p.debugln("sendICMP(): End")
return queue, nil
}