/*

 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.

 * 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

package sun.net;

import java.security.AccessController;

/**

 * Determines the ephemeral port range in use on this system.

 * If this cannot be determined, then the default settings

 * of the OS are returned.

 */

public final class PortConfig {

    private static int defaultUpper, defaultLower;

    private PortConfig() {}

    static {

        AccessController.doPrivileged(

            new java.security.PrivilegedAction<>() {

                public Void run() {

                    System.loadLibrary("net");

                    String os = System.getProperty("os.name");

                    if (os.startsWith("Linux")) {

                        defaultLower = 32768;

                        defaultUpper = 61000;

                    } else if (os.startsWith("SunOS")) {

                        defaultLower = 32768;

                        defaultUpper = 65535;

                    } else if (os.contains("OS X")) {

                        defaultLower = 49152;

                        defaultUpper = 65535;

                    } else if (os.startsWith("AIX")) {

                        // The ephemeral port is OS version dependent on AIX:

                        // http://publib.boulder.ibm.com/infocenter/aix/v7r1/topic/com.ibm.aix.rsct315.admin/bl503_ephport.htm

                        // However, on AIX 5.3 / 6.1 / 7.1 we always see the

                        // settings below by using:

                        // /usr/sbin/no -a | fgrep ephemeral

                        defaultLower = 32768;

                        defaultUpper = 65535;

                    } else {

                        throw new InternalError(

                            "sun.net.PortConfig: unknown OS");

                    }

                    return null;

                }

            });

        int v = getLower0();

        if (v == -1) {

            v = defaultLower;

        }

        lower = v;

        v = getUpper0();

        if (v == -1) {

            v = defaultUpper;

        }

        upper = v;

    }

    static native int getLower0();

    static native int getUpper0();

    public static int getLower() {

        return lower;

    }

    public static int getUpper() {

        return upper;

    }

}