add dhcp failing test

examples/tap/main.go

@@ -5,11 +5,9 @@ import (
 	"flag"
 	"fmt"
 	"log"
-	"log/slog"
 	"net"
 	"net/http"
 	"net/netip"
-	"runtime"
 	"strings"
 	"time"
 
@@ -87,26 +85,8 @@ func run() error {
 		return err
 	}
 	fmt.Println("listening on http://127.0.0.1:7070/recv  and  http://127.0.0.1:7070/send on hwaddr:", net.HardwareAddr(hwaddr[:]).String())
-	go http.ListenAndServe(":7070", sv)
-	const standbyDuration = 5 * time.Second
-	lastHit := time.Now().Add(-standbyDuration)
-	for {
-		result, err := sv.HandleTap()
-		if err != nil {
-			slog.Error("handletap:error", slog.String("err", err.Error()), slog.Any("result", result))
-		}
-		if result.Failed {
-			return errors.New("tap failed, exit program")
-		} else if result.ReceivedSize == 0 && result.SentSize == 0 {
-			if time.Since(lastHit) > standbyDuration {
-				time.Sleep(5 * time.Millisecond) // Enter standby.
-			} else {
-				runtime.Gosched()
-			}
-		} else {
-			lastHit = time.Now()
-		}
-	}
+	http.ListenAndServe(":7070", sv)
+	return errors.New("finished")
 }
 
 func getTCPData(frames []pcap.Frame, pkt []byte) (flags tcp.Flags, src, dst uint16) {