diff --git a/harvester/vendor/github.com/tatsushid/go-fastping/LICENSE b/harvester/vendor/github.com/tatsushid/go-fastping/LICENSE
new file mode 100644
index 0000000..abb8dee
--- /dev/null
+++ b/harvester/vendor/github.com/tatsushid/go-fastping/LICENSE
@@ -0,0 +1,20 @@
+The MIT License (MIT)
+
+Copyright (c) 2013 Tatsushi Demachi
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of
+this software and associated documentation files (the "Software"), to deal in
+the Software without restriction, including without limitation the rights to
+use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
+the Software, and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
+IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
diff --git a/harvester/vendor/github.com/tatsushid/go-fastping/README.md b/harvester/vendor/github.com/tatsushid/go-fastping/README.md
new file mode 100644
index 0000000..d77a261
--- /dev/null
+++ b/harvester/vendor/github.com/tatsushid/go-fastping/README.md
@@ -0,0 +1,54 @@
+go-fastping
+===========
+
+go-fastping is a Go language ICMP ping library, inspired by the `AnyEvent::FastPing`
+Perl module, for quickly sending ICMP ECHO REQUEST packets. Original Perl module
+is available at http://search.cpan.org/~mlehmann/AnyEvent-FastPing-2.01/
+
+All original functions haven't been implemented yet.
+
+[![GoDoc](https://godoc.org/github.com/tatsushid/go-fastping?status.svg)](https://godoc.org/github.com/tatsushid/go-fastping)
+
+## Installation
+
+Install and update with `go get -u github.com/tatsushid/go-fastping`
+
+## Examples
+
+Import this package and write
+
+```go
+p := fastping.NewPinger()
+ra, err := net.ResolveIPAddr("ip4:icmp", os.Args[1])
+if err != nil {
+	fmt.Println(err)
+	os.Exit(1)
+}
+p.AddIPAddr(ra)
+p.OnRecv = func(addr *net.IPAddr, rtt time.Duration) {
+	fmt.Printf("IP Addr: %s receive, RTT: %v\n", addr.String(), rtt)
+}
+p.OnIdle = func() {
+	fmt.Println("finish")
+}
+err = p.Run()
+if err != nil {
+	fmt.Println(err)
+}
+```
+
+The example sends an ICMP packet and waits for a response. If it receives a
+response, it calls the "receive" callback. After that, once MaxRTT time has
+passed, it calls the "idle" callback. For more details,
+refer [to the godoc][godoc], and if you need more examples,
+please see "cmd/ping/ping.go".
+
+## Caution
+This package implements ICMP ping using both raw socket and UDP. If your program
+uses this package in raw socket mode, it needs to be run as a root user.
+
+## License
+go-fastping is under MIT License. See the [LICENSE][license] file for details.
+
+[godoc]: http://godoc.org/github.com/tatsushid/go-fastping
+[license]: https://github.com/tatsushid/go-fastping/blob/master/LICENSE
diff --git a/harvester/vendor/github.com/tatsushid/go-fastping/fastping.go b/harvester/vendor/github.com/tatsushid/go-fastping/fastping.go
new file mode 100644
index 0000000..96950ca
--- /dev/null
+++ b/harvester/vendor/github.com/tatsushid/go-fastping/fastping.go
@@ -0,0 +1,685 @@
+// Package fastping is an ICMP ping library inspired by AnyEvent::FastPing Perl
+// module to send ICMP ECHO REQUEST packets quickly. Original Perl module is
+// available at
+// http://search.cpan.org/~mlehmann/AnyEvent-FastPing-2.01/
+//
+// It hasn't been fully implemented original functions yet.
+//
+// Here is an example:
+//
+//	p := fastping.NewPinger()
+//	ra, err := net.ResolveIPAddr("ip4:icmp", os.Args[1])
+//	if err != nil {
+//		fmt.Println(err)
+//		os.Exit(1)
+//	}
+//	p.AddIPAddr(ra)
+//	p.OnRecv = func(addr *net.IPAddr, rtt time.Duration) {
+//		fmt.Printf("IP Addr: %s receive, RTT: %v\n", addr.String(), rtt)
+//	}
+//	p.OnIdle = func() {
+//		fmt.Println("finish")
+//	}
+//	err = p.Run()
+//	if err != nil {
+//		fmt.Println(err)
+//	}
+//
+// It sends an ICMP packet and wait a response. If it receives a response,
+// it calls "receive" callback. After that, MaxRTT time passed, it calls
+// "idle" callback. If you need more example, please see "cmd/ping/ping.go".
+//
+// This library needs to run as a superuser for sending ICMP packets when
+// privileged raw ICMP endpoints is used so in such a case, to run go test
+// for the package, please run like a following
+//
+//	sudo go test
+//
+package fastping
+
+import (
+	"errors"
+	"fmt"
+	"log"
+	"math/rand"
+	"net"
+	"sync"
+	"syscall"
+	"time"
+
+	"golang.org/x/net/icmp"
+	"golang.org/x/net/ipv4"
+	"golang.org/x/net/ipv6"
+)
+
+const (
+	TimeSliceLength  = 8
+	ProtocolICMP     = 1
+	ProtocolIPv6ICMP = 58
+)
+
+var (
+	ipv4Proto = map[string]string{"ip": "ip4:icmp", "udp": "udp4"}
+	ipv6Proto = map[string]string{"ip": "ip6:ipv6-icmp", "udp": "udp6"}
+)
+
+func byteSliceOfSize(n int) []byte {
+	b := make([]byte, n)
+	for i := 0; i < len(b); i++ {
+		b[i] = 1
+	}
+
+	return b
+}
+
+func timeToBytes(t time.Time) []byte {
+	nsec := t.UnixNano()
+	b := make([]byte, 8)
+	for i := uint8(0); i < 8; i++ {
+		b[i] = byte((nsec >> ((7 - i) * 8)) & 0xff)
+	}
+	return b
+}
+
+func bytesToTime(b []byte) time.Time {
+	var nsec int64
+	for i := uint8(0); i < 8; i++ {
+		nsec += int64(b[i]) << ((7 - i) * 8)
+	}
+	return time.Unix(nsec/1000000000, nsec%1000000000)
+}
+
+func isIPv4(ip net.IP) bool {
+	return len(ip.To4()) == net.IPv4len
+}
+
+func isIPv6(ip net.IP) bool {
+	return len(ip) == net.IPv6len
+}
+
+func ipv4Payload(b []byte) []byte {
+	if len(b) < ipv4.HeaderLen {
+		return b
+	}
+	hdrlen := int(b[0]&0x0f) << 2
+	return b[hdrlen:]
+}
+
+type packet struct {
+	bytes []byte
+	addr  net.Addr
+}
+
+type context struct {
+	stop chan bool
+	done chan bool
+	err  error
+}
+
+func newContext() *context {
+	return &context{
+		stop: make(chan bool),
+		done: make(chan bool),
+	}
+}
+
+// Pinger represents ICMP packet sender/receiver
+type Pinger struct {
+	id  int
+	seq int
+	// key string is IPAddr.String()
+	addrs   map[string]*net.IPAddr
+	network string
+	source  string
+	source6 string
+	hasIPv4 bool
+	hasIPv6 bool
+	ctx     *context
+	mu      sync.Mutex
+
+	// Size in bytes of the payload to send
+	Size int
+	// Number of (nano,milli)seconds of an idle timeout. Once it passed,
+	// the library calls an idle callback function. It is also used for an
+	// interval time of RunLoop() method
+	MaxRTT time.Duration
+	// OnRecv is called with a response packet's source address and its
+	// elapsed time when Pinger receives a response packet.
+	OnRecv func(*net.IPAddr, time.Duration)
+	// OnIdle is called when MaxRTT time passed
+	OnIdle func()
+	// If Debug is true, it prints debug messages to stdout.
+	Debug bool
+}
+
+// NewPinger returns a new Pinger struct pointer
+func NewPinger() *Pinger {
+	rand.Seed(time.Now().UnixNano())
+	return &Pinger{
+		id:      rand.Intn(0xffff),
+		seq:     rand.Intn(0xffff),
+		addrs:   make(map[string]*net.IPAddr),
+		network: "ip",
+		source:  "",
+		source6: "",
+		hasIPv4: false,
+		hasIPv6: false,
+		Size:    TimeSliceLength,
+		MaxRTT:  time.Second,
+		OnRecv:  nil,
+		OnIdle:  nil,
+		Debug:   false,
+	}
+}
+
+// Network sets a network endpoints for ICMP ping and returns the previous
+// setting. network arg should be "ip" or "udp" string or if others are
+// specified, it returns an error. If this function isn't called, Pinger
+// uses "ip" as default.
+func (p *Pinger) Network(network string) (string, error) {
+	origNet := p.network
+	switch network {
+	case "ip":
+		fallthrough
+	case "udp":
+		p.network = network
+	default:
+		return origNet, errors.New(network + " can't be used as ICMP endpoint")
+	}
+	return origNet, nil
+}
+
+// Source sets ipv4/ipv6 source IP for sending ICMP packets and returns the previous
+// setting. Empty value indicates to use system default one (for both ipv4 and ipv6).
+func (p *Pinger) Source(source string) (string, error) {
+	// using ipv4 previous value for new empty one
+	origSource := p.source
+	if "" == source {
+		p.mu.Lock()
+		p.source = ""
+		p.source6 = ""
+		p.mu.Unlock()
+		return origSource, nil
+	}
+
+	addr := net.ParseIP(source)
+	if addr == nil {
+		return origSource, errors.New(source + " is not a valid textual representation of an IPv4/IPv6 address")
+	}
+
+	if isIPv4(addr) {
+		p.mu.Lock()
+		p.source = source
+		p.mu.Unlock()
+	} else if isIPv6(addr) {
+		origSource = p.source6
+		p.mu.Lock()
+		p.source6 = source
+		p.mu.Unlock()
+	} else {
+		return origSource, errors.New(source + " is not a valid textual representation of an IPv4/IPv6 address")
+	}
+
+	return origSource, nil
+}
+
+// AddIP adds an IP address to Pinger. ipaddr arg should be a string like
+// "192.0.2.1".
+func (p *Pinger) AddIP(ipaddr string) error {
+	addr := net.ParseIP(ipaddr)
+	if addr == nil {
+		return fmt.Errorf("%s is not a valid textual representation of an IP address", ipaddr)
+	}
+	p.mu.Lock()
+	p.addrs[addr.String()] = &net.IPAddr{IP: addr}
+	if isIPv4(addr) {
+		p.hasIPv4 = true
+	} else if isIPv6(addr) {
+		p.hasIPv6 = true
+	}
+	p.mu.Unlock()
+	return nil
+}
+
+// AddIPAddr adds an IP address to Pinger. ip arg should be a net.IPAddr
+// pointer.
+func (p *Pinger) AddIPAddr(ip *net.IPAddr) {
+	p.mu.Lock()
+	p.addrs[ip.String()] = ip
+	if isIPv4(ip.IP) {
+		p.hasIPv4 = true
+	} else if isIPv6(ip.IP) {
+		p.hasIPv6 = true
+	}
+	p.mu.Unlock()
+}
+
+// RemoveIP removes an IP address from Pinger. ipaddr arg should be a string
+// like "192.0.2.1".
+func (p *Pinger) RemoveIP(ipaddr string) error {
+	addr := net.ParseIP(ipaddr)
+	if addr == nil {
+		return fmt.Errorf("%s is not a valid textual representation of an IP address", ipaddr)
+	}
+	p.mu.Lock()
+	delete(p.addrs, addr.String())
+	p.mu.Unlock()
+	return nil
+}
+
+// RemoveIPAddr removes an IP address from Pinger. ip arg should be a net.IPAddr
+// pointer.
+func (p *Pinger) RemoveIPAddr(ip *net.IPAddr) {
+	p.mu.Lock()
+	delete(p.addrs, ip.String())
+	p.mu.Unlock()
+}
+
+// AddHandler adds event handler to Pinger. event arg should be "receive" or
+// "idle" string.
+//
+// **CAUTION** This function is deprecated. Please use OnRecv and OnIdle field
+// of Pinger struct to set following handlers.
+//
+// "receive" handler should be
+//
+//	func(addr *net.IPAddr, rtt time.Duration)
+//
+// type function. The handler is called with a response packet's source address
+// and its elapsed time when Pinger receives a response packet.
+//
+// "idle" handler should be
+//
+//	func()
+//
+// type function. The handler is called when MaxRTT time passed. For more
+// detail, please see Run() and RunLoop().
+func (p *Pinger) AddHandler(event string, handler interface{}) error {
+	switch event {
+	case "receive":
+		if hdl, ok := handler.(func(*net.IPAddr, time.Duration)); ok {
+			p.mu.Lock()
+			p.OnRecv = hdl
+			p.mu.Unlock()
+			return nil
+		}
+		return errors.New("receive event handler should be `func(*net.IPAddr, time.Duration)`")
+	case "idle":
+		if hdl, ok := handler.(func()); ok {
+			p.mu.Lock()
+			p.OnIdle = hdl
+			p.mu.Unlock()
+			return nil
+		}
+		return errors.New("idle event handler should be `func()`")
+	}
+	return errors.New("No such event: " + event)
+}
+
+// Run invokes a single send/receive procedure. It sends packets to all hosts
+// which have already been added by AddIP() etc. and wait those responses. When
+// it receives a response, it calls "receive" handler registered by AddHander().
+// After MaxRTT seconds, it calls "idle" handler and returns to caller with
+// an error value. It means it blocks until MaxRTT seconds passed. For the
+// purpose of sending/receiving packets over and over, use RunLoop().
+func (p *Pinger) Run() error {
+	p.mu.Lock()
+	p.ctx = newContext()
+	p.mu.Unlock()
+	p.run(true)
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	return p.ctx.err
+}
+
+// RunLoop invokes send/receive procedure repeatedly. It sends packets to all
+// hosts which have already been added by AddIP() etc. and wait those responses.
+// When it receives a response, it calls "receive" handler registered by
+// AddHander(). After MaxRTT seconds, it calls "idle" handler, resend packets
+// and wait those response. MaxRTT works as an interval time.
+//
+// This is a non-blocking method so immediately returns. If you want to monitor
+// and stop sending packets, use Done() and Stop() methods. For example,
+//
+//	p.RunLoop()
+//	ticker := time.NewTicker(time.Millisecond * 250)
+//	select {
+//	case <-p.Done():
+//		if err := p.Err(); err != nil {
+//			log.Fatalf("Ping failed: %v", err)
+//		}
+//	case <-ticker.C:
+//		break
+//	}
+//	ticker.Stop()
+//	p.Stop()
+//
+// For more details, please see "cmd/ping/ping.go".
+func (p *Pinger) RunLoop() {
+	p.mu.Lock()
+	p.ctx = newContext()
+	p.mu.Unlock()
+	go p.run(false)
+}
+
+// Done returns a channel that is closed when RunLoop() is stopped by an error
+// or Stop(). It must be called after RunLoop() call. If not, it causes panic.
+func (p *Pinger) Done() <-chan bool {
+	return p.ctx.done
+}
+
+// Stop stops RunLoop(). It must be called after RunLoop(). If not, it causes
+// panic.
+func (p *Pinger) Stop() {
+	p.debugln("Stop(): close(p.ctx.stop)")
+	close(p.ctx.stop)
+	p.debugln("Stop(): <-p.ctx.done")
+	<-p.ctx.done
+}
+
+// Err returns an error that is set by RunLoop(). It must be called after
+// RunLoop(). If not, it causes panic.
+func (p *Pinger) Err() error {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	return p.ctx.err
+}
+
+func (p *Pinger) listen(netProto string, source string) *icmp.PacketConn {
+	conn, err := icmp.ListenPacket(netProto, source)
+	if err != nil {
+		p.mu.Lock()
+		p.ctx.err = err
+		p.mu.Unlock()
+		p.debugln("Run(): close(p.ctx.done)")
+		close(p.ctx.done)
+		return nil
+	}
+	return conn
+}
+
+func (p *Pinger) run(once bool) {
+	p.debugln("Run(): Start")
+	var conn, conn6 *icmp.PacketConn
+	if p.hasIPv4 {
+		if conn = p.listen(ipv4Proto[p.network], p.source); conn == nil {
+			return
+		}
+		defer conn.Close()
+	}
+
+	if p.hasIPv6 {
+		if conn6 = p.listen(ipv6Proto[p.network], p.source6); conn6 == nil {
+			return
+		}
+		defer conn6.Close()
+	}
+
+	recv := make(chan *packet, 1)
+	recvCtx := newContext()
+	wg := new(sync.WaitGroup)
+
+	p.debugln("Run(): call recvICMP()")
+	if conn != nil {
+		wg.Add(1)
+		go p.recvICMP(conn, recv, recvCtx, wg)
+	}
+	if conn6 != nil {
+		wg.Add(1)
+		go p.recvICMP(conn6, recv, recvCtx, wg)
+	}
+
+	p.debugln("Run(): call sendICMP()")
+	queue, err := p.sendICMP(conn, conn6)
+
+	ticker := time.NewTicker(p.MaxRTT)
+
+mainloop:
+	for {
+		select {
+		case <-p.ctx.stop:
+			p.debugln("Run(): <-p.ctx.stop")
+			break mainloop
+		case <-recvCtx.done:
+			p.debugln("Run(): <-recvCtx.done")
+			p.mu.Lock()
+			err = recvCtx.err
+			p.mu.Unlock()
+			break mainloop
+		case <-ticker.C:
+			p.mu.Lock()
+			handler := p.OnIdle
+			p.mu.Unlock()
+			if handler != nil {
+				handler()
+			}
+			if once || err != nil {
+				break mainloop
+			}
+			p.debugln("Run(): call sendICMP()")
+			queue, err = p.sendICMP(conn, conn6)
+		case r := <-recv:
+			p.debugln("Run(): <-recv")
+			p.procRecv(r, queue)
+		}
+	}
+
+	ticker.Stop()
+
+	p.debugln("Run(): close(recvCtx.stop)")
+	close(recvCtx.stop)
+	p.debugln("Run(): wait recvICMP()")
+	wg.Wait()
+
+	p.mu.Lock()
+	p.ctx.err = err
+	p.mu.Unlock()
+
+	p.debugln("Run(): close(p.ctx.done)")
+	close(p.ctx.done)
+	p.debugln("Run(): End")
+}
+
+func (p *Pinger) sendICMP(conn, conn6 *icmp.PacketConn) (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 icmp.Type
+		var cn *icmp.PacketConn
+		if isIPv4(addr.IP) {
+			typ = ipv4.ICMPTypeEcho
+			cn = conn
+		} else if isIPv6(addr.IP) {
+			typ = ipv6.ICMPTypeEchoRequest
+			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 := (&icmp.Message{
+			Type: typ, Code: 0,
+			Body: &icmp.Echo{
+				ID: p.id, Seq: p.seq,
+				Data: t,
+			},
+		}).Marshal(nil)
+		p.mu.Unlock()
+		if err != nil {
+			wg.Wait()
+			return queue, err
+		}
+
+		queue[key] = addr
+		var dst net.Addr = addr
+		if p.network == "udp" {
+			dst = &net.UDPAddr{IP: addr.IP, Zone: addr.Zone}
+		}
+
+		p.debugln("sendICMP(): Invoke goroutine")
+		wg.Add(1)
+		go func(conn *icmp.PacketConn, ra net.Addr, b []byte) {
+			for {
+				if _, err := conn.WriteTo(bytes, ra); err != nil {
+					if neterr, ok := err.(*net.OpError); ok {
+						if neterr.Err == syscall.ENOBUFS {
+							continue
+						}
+					}
+				}
+				break
+			}
+			p.debugln("sendICMP(): WriteTo End")
+			wg.Done()
+		}(cn, dst, bytes)
+	}
+	wg.Wait()
+	p.debugln("sendICMP(): End")
+	return queue, nil
+}
+
+func (p *Pinger) recvICMP(conn *icmp.PacketConn, recv chan<- *packet, ctx *context, wg *sync.WaitGroup) {
+	p.debugln("recvICMP(): Start")
+	for {
+		select {
+		case <-ctx.stop:
+			p.debugln("recvICMP(): <-ctx.stop")
+			wg.Done()
+			p.debugln("recvICMP(): wg.Done()")
+			return
+		default:
+		}
+
+		bytes := make([]byte, 512)
+		conn.SetReadDeadline(time.Now().Add(time.Millisecond * 100))
+		p.debugln("recvICMP(): ReadFrom Start")
+		_, ra, err := conn.ReadFrom(bytes)
+		p.debugln("recvICMP(): ReadFrom End")
+		if err != nil {
+			if neterr, ok := err.(*net.OpError); ok {
+				if neterr.Timeout() {
+					p.debugln("recvICMP(): Read Timeout")
+					continue
+				} else {
+					p.debugln("recvICMP(): OpError happen", err)
+					p.mu.Lock()
+					ctx.err = err
+					p.mu.Unlock()
+					p.debugln("recvICMP(): close(ctx.done)")
+					close(ctx.done)
+					p.debugln("recvICMP(): wg.Done()")
+					wg.Done()
+					return
+				}
+			}
+		}
+		p.debugln("recvICMP(): p.recv <- packet")
+
+		select {
+		case recv <- &packet{bytes: bytes, addr: ra}:
+		case <-ctx.stop:
+			p.debugln("recvICMP(): <-ctx.stop")
+			wg.Done()
+			p.debugln("recvICMP(): wg.Done()")
+			return
+		}
+	}
+}
+
+func (p *Pinger) procRecv(recv *packet, queue map[string]*net.IPAddr) {
+	var ipaddr *net.IPAddr
+	switch adr := recv.addr.(type) {
+	case *net.IPAddr:
+		ipaddr = adr
+	case *net.UDPAddr:
+		ipaddr = &net.IPAddr{IP: adr.IP, Zone: adr.Zone}
+	default:
+		return
+	}
+
+	addr := ipaddr.String()
+	p.mu.Lock()
+	if _, ok := p.addrs[addr]; !ok {
+		p.mu.Unlock()
+		return
+	}
+	p.mu.Unlock()
+
+	var bytes []byte
+	var proto int
+	if isIPv4(ipaddr.IP) {
+		if p.network == "ip" {
+			bytes = ipv4Payload(recv.bytes)
+		} else {
+			bytes = recv.bytes
+		}
+		proto = ProtocolICMP
+	} else if isIPv6(ipaddr.IP) {
+		bytes = recv.bytes
+		proto = ProtocolIPv6ICMP
+	} else {
+		return
+	}
+
+	var m *icmp.Message
+	var err error
+	if m, err = icmp.ParseMessage(proto, bytes); err != nil {
+		return
+	}
+
+	if m.Type != ipv4.ICMPTypeEchoReply && m.Type != ipv6.ICMPTypeEchoReply {
+		return
+	}
+
+	var rtt time.Duration
+	switch pkt := m.Body.(type) {
+	case *icmp.Echo:
+		p.mu.Lock()
+		if pkt.ID == p.id && pkt.Seq == p.seq {
+			rtt = time.Since(bytesToTime(pkt.Data[:TimeSliceLength]))
+		}
+		p.mu.Unlock()
+	default:
+		return
+	}
+
+	if _, ok := queue[addr]; ok {
+		delete(queue, addr)
+		p.mu.Lock()
+		handler := p.OnRecv
+		p.mu.Unlock()
+		if handler != nil {
+			handler(ipaddr, rtt)
+		}
+	}
+}
+
+func (p *Pinger) debugln(args ...interface{}) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.Debug {
+		log.Println(args...)
+	}
+}
+
+func (p *Pinger) debugf(format string, args ...interface{}) {
+	p.mu.Lock()
+	defer p.mu.Unlock()
+	if p.Debug {
+		log.Printf(format, args...)
+	}
+}