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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

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import com.sun.jdi.Bootstrap;

import com.sun.jdi.VirtualMachine;

import com.sun.jdi.connect.Connector;

import com.sun.jdi.connect.ListeningConnector;

import jdk.test.lib.apps.LingeredApp;

import java.net.Inet4Address;

import java.net.Inet6Address;

import java.net.InetAddress;

import java.net.NetworkInterface;

import java.net.SocketException;

import java.util.Arrays;

import java.util.Enumeration;

import java.util.Iterator;

import java.util.LinkedList;

import java.util.List;

import java.util.Map;

import java.util.concurrent.Callable;

import java.util.concurrent.ExecutorService;

import java.util.concurrent.Executors;

import java.util.concurrent.TimeUnit;

/*

 * @test

 * @bug 8184770

 * @summary Tests for JDWP agent attach functionality (including IPv6 support)

 * @library /test/lib

 *

 * @build HelloWorld JdwpAttachTest

 * @run main/othervm JdwpAttachTest

 */

public class JdwpAttachTest {

    public static void main(String[] args) throws Exception {

        List<InetAddress> addresses = getAddresses();

        boolean ipv4EnclosedTested = false;

        boolean ipv6EnclosedTested = false;

        for (InetAddress addr: addresses) {

            // also test that addresses enclosed in square brackets are supported

            attachTest(addr.getHostAddress(), addr.getHostAddress());

            // listening on "*" should accept connections from all addresses

            attachTest("*", addr.getHostAddress());

            // test that addresses enclosed in square brackets are supported.

            if (addr instanceof Inet4Address && !ipv4EnclosedTested) {

                attachTest("[" + addr.getHostAddress() + "]", "[" + addr.getHostAddress() + "]");

                ipv4EnclosedTested = true;

            }

            if (addr instanceof Inet6Address && !ipv6EnclosedTested) {

                attachTest("[" + addr.getHostAddress() + "]", "[" + addr.getHostAddress() + "]");

                ipv6EnclosedTested = true;

            }

        }

        // by using "localhost" or empty hostname

        // we should be able to attach to both IPv4 and IPv6 addresses (127.0.0.1 & ::1)

        InetAddress localAddresses[] = InetAddress.getAllByName("localhost");

        for (int i = 0; i < localAddresses.length; i++) {

            attachTest(localAddresses[i].getHostAddress(), "");

        }

    }

    private static void attachTest(String listenAddress, String connectAddresses)

            throws Exception {

        log("Starting listening at " + listenAddress);

        ListeningConnector connector = getListenConnector();

        Map<String, Connector.Argument> args = connector.defaultArguments();

        setConnectorArg(args, "localAddress", listenAddress);

        setConnectorArg(args, "port", "0");

        String actualAddress = connector.startListening(args);

        String actualPort = actualAddress.substring(actualAddress.lastIndexOf(':') + 1);

        String port = args.get("port").value();

        // port from connector.startListening must be the same as values from arguments

        if (!port.equals(actualPort)) {

            throw new RuntimeException("values from connector.startListening (" + actualPort

                    + " is not equal to values from arguments (" + port + ")");

        }

        log("Listening port: " + port);

        log("Attaching from " + connectAddresses);

        try {

            ExecutorService executor = Executors.newSingleThreadExecutor();

            executor.submit((Callable<Exception>)() -> {

                VirtualMachine vm = connector.accept(args);

                log("ACCEPTED.");

                vm.dispose();

                return null;

            });

            executor.shutdown();

            LingeredApp debuggee = LingeredApp.startApp(

                    Arrays.asList("-agentlib:jdwp=transport=dt_socket"

                                +",address=" + connectAddresses + ":" + port

                                + ",server=n,suspend=n"));

            debuggee.stopApp();

            executor.awaitTermination(20, TimeUnit.SECONDS);

        } finally {

            connector.stopListening(args);

        }

    }

    private static List<InetAddress> getAddresses() {

        List<InetAddress> result = new LinkedList<>();

        try {

            Enumeration<NetworkInterface> networkInterfaces = NetworkInterface.getNetworkInterfaces();

            while (networkInterfaces.hasMoreElements()) {

                NetworkInterface iface = networkInterfaces.nextElement();

                try {

                    if (iface.isUp()) {

                        Enumeration<InetAddress> addresses = iface.getInetAddresses();

                        while (addresses.hasMoreElements()) {

                            InetAddress addr = addresses.nextElement();

                            // Java reports link local addresses with named scope,

                            // but Windows sockets routines support only numeric scope id.

                            // skip such addresses.

                            if (addr instanceof Inet6Address) {

                                Inet6Address addr6 = (Inet6Address)addr;

                                if (addr6.getScopedInterface() != null) {

                                    continue;

                                }

                            }

                            log(" - (" + addr.getClass().getSimpleName() + ") " + addr.getHostAddress());

                            result.add(addr);

                        }

                    }

                } catch (SocketException e) {

                    log("Interface " + iface.getDisplayName() + ": failed to get addresses");

                }

            }

        } catch (SocketException e) {

            log("Interface enumeration error: " + e);

        }

        return result;

    }

    private static String LISTEN_CONNECTOR = "com.sun.jdi.SocketListen";

    private static ListeningConnector getListenConnector() {

        return (ListeningConnector)getConnector(LISTEN_CONNECTOR);

    }

    private static Connector getConnector(String name) {

        List<Connector> connectors = Bootstrap.virtualMachineManager().allConnectors();

        for (Iterator<Connector> iter = connectors.iterator(); iter.hasNext(); ) {

            Connector connector = iter.next();

            if (connector.name().equalsIgnoreCase(name)) {

                return connector;

            }

        }

        throw new IllegalArgumentException("Connector " + name + " not found");

    }

    private static void setConnectorArg(Map<String, Connector.Argument> args, String name, String value) {

        Connector.Argument arg = args.get(name);

        if (arg == null) {

            throw new IllegalArgumentException("Argument " + name + " is not defined");

        }

        arg.setValue(value);

    }

    private static void log(Object o) {

        System.out.println(String.valueOf(o));

    }

}