/*

 * Copyright (c) 2017, 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.

 *

 * 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

 * or visit www.oracle.com if you need additional information or have any

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 */

/*

 * @test

 * @bug 8164900

 * @summary Test for ExtendedOpenOption.DIRECT flag

 * @requires (os.family == "linux" | os.family == "solaris"

 *         | os.family == "aix")

 * @library /test/lib

 * @build jdk.test.lib.Platform

 * @run main/native DirectIOTest

 */

import java.io.*;

import java.nio.ByteBuffer;

import java.nio.CharBuffer;

import java.nio.channels.*;

import java.nio.channels.FileChannel;

import java.nio.file.Paths;

import java.nio.file.Path;

import java.nio.file.Files;

import jdk.test.lib.Platform;

import java.nio.file.FileStore;

import java.nio.file.StandardOpenOption;

import com.sun.nio.file.ExtendedOpenOption;

public class DirectIOTest {

    private static final int SIZE = 4096;

    private static void testWrite(Path p) throws Exception {

        try (FileChannel fc = FileChannel.open(p, StandardOpenOption.WRITE,

             ExtendedOpenOption.DIRECT)) {

            FileStore fs = Files.getFileStore(p);

            int alignment = (int)fs.getBlockSize();

            ByteBuffer src = ByteBuffer.allocateDirect(SIZE + alignment - 1)

                                       .alignedSlice(alignment);

            for (int j = 0; j < SIZE; j++) {

                src.put((byte)0);

            }

            src.flip();

            fc.write(src);

        }

    }

    private static void testRead(Path p) throws Exception {

        try (FileChannel fc = FileChannel.open(p, ExtendedOpenOption.DIRECT)) {

            FileStore fs = Files.getFileStore(p);

            int alignment = (int)fs.getBlockSize();

            ByteBuffer dest = ByteBuffer.allocateDirect(SIZE + alignment - 1)

                                        .alignedSlice(alignment);

            fc.read(dest);

        }

    }

    public static Path createTempFile() throws IOException {

        return Files.createTempFile(

            Paths.get(System.getProperty("test.dir", ".")), "test", null);

    }

    public static boolean isDirectIOSupportedByFS(Path p) throws Exception {

        boolean supported = true;

        if (Platform.isSolaris()) {

            String fsType = Files.getFileStore(p).type();

            if (!fsType.equals("nfs") && !fsType.equals("ufs")) {

                // print a message and return without failing

                System.out.format("Skipping test: file system type %s of "

                    + "FileStore of %s is neither nfs nor ufs.%n", fsType, p);

                supported = false;

            }

        }

        return supported;

    }

    private static boolean isFileInCache(Path p) {

        String path = p.toString();

        return isFileInCache0(SIZE, path);

    }

    private static native boolean isFileInCache0(int size, String path);

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

        Path p = createTempFile();

        if (!isDirectIOSupportedByFS(p)) {

            Files.delete(p);

            return;

        }

        System.loadLibrary("DirectIO");

        try {

            testWrite(p);

            if (isFileInCache(p)) {

                throw new RuntimeException("DirectIO is not working properly with "

                    + "write. File still exists in cache!");

            }

            testRead(p);

            if (isFileInCache(p)) {

                throw new RuntimeException("DirectIO is not working properly with "

                    + "read. File still exists in cache!");

            }

        } finally {

            Files.delete(p);

        }

    }

}