Capturing the packets without the callback

Handling a callback is sometimes not practical, it often makes the program more complex. So we need an alternative method to capture the packets without a callback.

Note: Both "PacketHeader" and "PacketBuffer" is not freed by the caller, and not guaranteed to be valid after the next call. If you needs it to remain valid, you must make a copy of it.

Docs: libpcap, javadoc.

Java

public static void main(String[] _args)
    throws ErrorException, PermissionDeniedException, PromiscuousModePermissionDeniedException,
        TimestampPrecisionNotSupportedException, RadioFrequencyModeNotSupportedException,
        NoSuchDeviceException, ActivatedException, InterfaceNotUpException,
        InterfaceNotSupportTimestampTypeException {
  var service = Service.Creator.create("PcapService");
  try (var pcap = service.live(service.interfaces(), new DefaultLiveOptions())) {
    PacketHeader header = pcap.allocate(PacketHeader.class);
    PacketBuffer buffer = pcap.allocate(PacketBuffer.class);
    for (int i = 0; i < 10; i++) {
      try {
        pcap.nextEx(header, buffer);
        System.out.println("Header   : " + header);
        System.out.println("Packet   : " + buffer);
      } catch (BreakException e) {
        System.err.println(e.getMessage());
      } catch (TimeoutException e) {
        System.err.println(e.getMessage());
      }
    }
  }
}

Kotlin

fun main() {
  val service = Service.Creator.create("PcapService")
  val pcap = service.live(service.interfaces(), DefaultLiveOptions())
  pcap.setFilter("icmp", true)
  val header = pcap.allocate(PacketHeader::class.java)
  val buffer = pcap.allocate(PacketBuffer::class.java)
  for (i in 0..9) {
    try {
      pcap.nextEx(header, buffer)
      println("Header   : $header")
      println("Packet   : $buffer")
    } catch (e: BreakException) {
      System.err.println(e.message)
    } catch (e: TimeoutException) {
      System.err.println(e.message)
    }
  }
  pcap.close()
}

Scala

def main(_args: Array[String]): Unit = {
  val service = Service.Creator.create("PcapService")
  val pcap = service.live(service.interfaces(), new DefaultLiveOptions())
  val header = pcap.allocate(classOf[PacketHeader])
  val buffer = pcap.allocate(classOf[PacketBuffer])
  for (i <- 0 until 10) {
    try {
      pcap.nextEx(header, buffer)
      System.out.println("Header   : " + header)
      System.out.println("Packet   : " + buffer)
    } catch {
      case e: BreakException =>
        System.err.println(e.getMessage)
      case e: TimeoutException =>
        System.err.println(e.getMessage)
      case e: ErrorException =>
        System.err.println(e.getMessage)
    }
  }
  pcap.close()
}

Clojure

(defn -main
  [& args]
  (def service (. Service$Creator (create "PcapService")))
  (def pcap (.live service (.interfaces service) (DefaultLiveOptions.)))
  (def header (.allocate pcap pcap.spi.PacketHeader))
  (def buffer (.allocate pcap pcap.spi.PacketBuffer))
  (dotimes [n 10]
    (.nextEx pcap header buffer)
    (println header)
    (println buffer))
  (.close pcap))