test/hotspot/jtreg/vmTestbase/nsk/jvmti/unit/ForceEarlyReturn/earlyretint.java

/*
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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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package nsk.jvmti.unit.ForceEarlyReturn;

import java.io.PrintStream;
import nsk.share.Consts;

public class earlyretint {

    // Any 5n-1 depth would be correct because we subsequencially run
    // methods returning boolean, byte, char, short and int types.
    // The top-most frame on the stack must be countDownInt().
    final static int NESTING_DEPTH   = 9;

    // This value is forced to return from the method countDownInt().
    final static int EXPECTED_RETVAL = 404;

    static boolean failed = false;

    static {
        try {
            System.loadLibrary("earlyretint");
        } catch (UnsatisfiedLinkError ule) {
            System.err.println("Could not load earlyretint library");
            System.err.println("java.library.path:"
                + System.getProperty("java.library.path"));
            throw ule;
        }
    }

    native static void getReady(Class cls, int depth);
    native static int check();
    native static void printInt(int val);

    public static void main(String args[]) {
        args = nsk.share.jvmti.JVMTITest.commonInit(args);

        // produce JCK-like exit status.
        int errCode = run(args, System.out);
        if (failed) {
            errCode = Consts.TEST_FAILED;
        }
        System.exit(errCode + Consts.JCK_STATUS_BASE);
    }

    public static int run(String args[], PrintStream out) {
        earlyretThread earlyretThr = new earlyretThread();
        getReady(earlyretThread.class, NESTING_DEPTH + 1);

        earlyretThr.start();
        try {
            earlyretThr.join();
        } catch (InterruptedException e) {
            throw new Error("Unexpected " + e);
        }

        return check();
    }

    // Tested thread class
    static class earlyretThread extends Thread {
        public void run() {
            long val0 = 9009; // an arbitrary value
            /* Start a chain of recursive calls with NESTING_DEPTH.
             * Then ForceEarlyReturn will be called in the JVMTI native
             * agent NESTING_DEPTH times to return from all the frames.
             * The chain of the ForceEarlyReturn calls starts at the
             * JVMTI Breakpoint event and continues at each Step event
             * until return from the first frame of the countDownInt.
             * The breakpoint is set in the checkPoint() method.
             */
            int val1  = countDownInt(NESTING_DEPTH);
            long val2 = 2222; // an arbitrary value

            earlyretint.printInt(val1);

            if (val1 != EXPECTED_RETVAL) {
                System.out.println(" Falure: wrong value returned: " + val1);
                failed = true;
            } else {
                System.out.println(" Success: right value returned: " + val1);
            }
        }

        // countDownInt calls countDownShort recursively
        public int countDownInt(int nestingCount) {
            int ret = 0;
            if (nestingCount > 0) {
                ret = (int) countDownShort(nestingCount - 1);
                System.out.println("countDownInt Return value: " + ret);
            } else {
                checkPoint(); // A breakpoint is set in this method
            }
            return ret;
        }

        // countDownShort calls countDownChar recursively
        public short countDownShort(int nestingCount) {
            short ret = 0;
            if (nestingCount > 0) {
                ret = (short) countDownChar(nestingCount - 1);
                System.out.println("countDownInt Return value: " + ret);
            } else {
                checkPoint(); // A breakpoint is set in this method
            }
            return ret;
        }

        // countDownChar calls countDownByte recursively
        public char countDownChar(int nestingCount) {
            char ret = 0;
            if (nestingCount > 0) {
                ret = (char) countDownByte(nestingCount - 1);
                System.out.println("countDownInt Return value: " + ret);
            } else {
                checkPoint(); // A breakpoint is set in this method
            }
            return ret;
        }

        // countDownByte calls countDownBoolean recursively
        public byte countDownByte(int nestingCount) {
            boolean ret = false;
            if (nestingCount > 0) {
                ret = countDownBoolean(nestingCount - 1);
                System.out.println("countDownInt Return value: " + ret);
            } else {
                checkPoint(); // A breakpoint is set in this method
            }
            return (byte) ((ret) ? 1 : 0);
        }

        // countDownBoolean calls countDownInt recursively
        public boolean countDownBoolean(int nestingCount) {
            int ret = 0;
            if (nestingCount > 0) {
                ret = countDownInt(nestingCount - 1);
                System.out.println("countDownInt Return value: " + ret);
            } else {
                checkPoint(); // A breakpoint is set in this method
            }
            return (ret != 0);
        }

        // dummy method to be breakpointed in the JVMTI agent
        void checkPoint() {
        }
    }
}