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

 *

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 * 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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 */

/*

 * @test

 * @bug 8049695

 * @summary Ensure shmem transport works with long names

 * @requires os.family == "windows"

 * @library /test/lib

 * @run main/othervm ShMemLongName

 */

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.InputStream;

import java.util.Collections;

import java.util.Map;

import com.sun.jdi.Bootstrap;

import com.sun.jdi.VirtualMachine;

import com.sun.jdi.connect.AttachingConnector;

import com.sun.jdi.connect.Connector;

import jdk.test.lib.process.ProcessTools;

public class ShMemLongName {

    private static final int maxShMemLength = 49;

    private static final String transport = "dt_shmem";

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

        // test with the maximum supported shmem name length

        String shmemName = ("ShMemLongName" + ProcessHandle.current().pid()

                                    + String.join("", Collections.nCopies(maxShMemLength, "x"))

                                 ).substring(0, maxShMemLength);

        Process target = getTarget(shmemName).start();

        try {

            waitForReady(target);

            log("attaching to the VM...");

            AttachingConnector ac = Bootstrap.virtualMachineManager().attachingConnectors()

                    .stream()

                    .filter(c -> transport.equals(c.transport().name()))

                    .findFirst()

                    .orElseThrow(() -> new RuntimeException("Failed to find transport " + transport));

            Map<String, Connector.Argument> acArgs = ac.defaultArguments();

            acArgs.get("name").setValue(shmemName);

            VirtualMachine vm = ac.attach(acArgs);

            log("attached. test(1) PASSED.");

            vm.dispose();

        } finally {

            target.destroy();

            target.waitFor();

        }

        // extra test: ensure using of too-long name fails gracefully

        // (shmemName + "X") is expected to be "too long".

        ProcessTools.executeProcess(getTarget(shmemName + "X"))

                .shouldContain("address strings longer than")

                .shouldHaveExitValue(2);

        log("test(2) PASSED.");

    }

    private static void log(String s) {

        System.out.println(s);

        System.out.flush();

    }

    // creates target process builder for the specified shmem transport name

    private static ProcessBuilder getTarget(String shmemName) throws IOException {

        log("starting target with shmem name: '" + shmemName + "'...");

        return ProcessTools.createJavaProcessBuilder(

                "-Xdebug",

                "-Xrunjdwp:transport=" + transport + ",server=y,suspend=n,address=" + shmemName,

                "ShMemLongName$Target");

    }

    private static void waitForReady(Process target) throws Exception {

        InputStream os = target.getInputStream();

        try (BufferedReader reader = new BufferedReader(new InputStreamReader(os))) {

            String line;

            while ((line = reader.readLine()) != null) {

                if (line.equals(Target.readyString)) {

                    return;

                }

            }

        }

    }

    public static class Target {

        public static final String readyString = "Ready";

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

            log(readyString);

            while (true) {

                Thread.sleep(1000);

            }

        }

    }

}