Initial import.

cmd/ping/ping.go

@@ -0,0 +1,73 @@
+package main
+
+import (
+	"fmt"
+	"github.com/tatsushid/go-fastping"
+	"net"
+	"os"
+	"os/signal"
+	"syscall"
+	"time"
+)
+
+type response struct {
+	addr *net.IPAddr
+	rtt  time.Duration
+}
+
+func main() {
+	if len(os.Args) != 2 {
+		fmt.Fprintf(os.Stderr, "Usage: %s {hostname}\n", os.Args[0])
+		os.Exit(1)
+	}
+	p := fastping.NewPinger()
+	ra, err := net.ResolveIPAddr("ip4:icmp", os.Args[1])
+	if err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+
+	results := make(map[string]*response)
+	results[ra.String()] = nil
+	p.AddIPAddr(ra)
+
+	onRecv, onIdle := make(chan *response), make(chan bool)
+	p.AddHandler("receive", func(addr *net.IPAddr, t time.Duration) {
+		onRecv <- &response{addr: addr, rtt: t}
+	})
+	p.AddHandler("idle", func() {
+		onIdle <- true
+	})
+
+	p.MaxRTT = time.Second
+	quit := p.RunLoop()
+
+	c := make(chan os.Signal, 1)
+	signal.Notify(c, os.Interrupt)
+	signal.Notify(c, syscall.SIGTERM)
+
+loop:
+	for {
+		select {
+		case <-c:
+			fmt.Println("get interrupted")
+			break loop
+		case res := <-onRecv:
+			if _, ok := results[res.addr.String()]; ok {
+				results[res.addr.String()] = res
+			}
+		case <-onIdle:
+			for host, r := range results {
+				if r == nil {
+					fmt.Printf("%s : unreachable %v\n", host, time.Now())
+				} else {
+					fmt.Printf("%s : %v %v\n", host, r.rtt, time.Now())
+				}
+				results[host] = nil
+			}
+		}
+	}
+	wait := make(chan bool)
+	quit <- wait
+	<-wait
+}