/*

 * Copyright (c) 2017, 2018, 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

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 * questions.

 */

package jdk.test.lib.cds;

import java.io.IOException;

import java.io.File;

import java.io.FileOutputStream;

import java.io.PrintStream;

import java.text.SimpleDateFormat;

import java.util.ArrayList;

import java.util.Date;

import jdk.test.lib.Utils;

import jdk.test.lib.process.OutputAnalyzer;

import jdk.test.lib.process.ProcessTools;

// This class contains common test utilities for testing CDS

public class CDSTestUtils {

    public interface Checker {

        public void check(OutputAnalyzer output) throws Exception;

    }

    /*

     * INTRODUCTION

     *

     * When testing various CDS functionalities, we need to launch JVM processes

     * using a "launch method" (such as TestCommon.run), and analyze the results of these

     * processes.

     *

     * While typical jtreg tests would use OutputAnalyzer in such cases, due to the

     * complexity of CDS failure modes, we have added the CDSTestUtils.Result class

     * to make the analysis more convenient and less error prone.

     *

     * A Java process can end in one of the following 4 states:

     *

     *    1: Unexpected error - such as JVM crashing. In this case, the "launch method"

     *                          will throw a RuntimeException.

     *    2: Mapping Failure  - this happens when the OS (intermittently) fails to map the

     *                          CDS archive, normally caused by Address Space Layout Randomization.

     *                          We usually treat this as "pass".

     *    3: Normal Exit      - the JVM process has finished without crashing, and the exit code is 0.

     *    4: Abnormal Exit    - the JVM process has finished without crashing, and the exit code is not 0.

     *

     * In most test cases, we need to check the JVM process's output in cases 3 and 4. However, we need

     * to make sure that our test code is not confused by case 2.

     *

     * For example, a JVM process is expected to print the string "Hi" and exit with 0. With the old

     * CDSTestUtils.runWithArchive API, the test may be written as this:

     *

     *     OutputAnalyzer out = CDSTestUtils.runWithArchive(args);

     *     out.shouldContain("Hi");

     *

     * However, if the JVM process fails with mapping failure, the string "Hi" will not be in the output,

     * and your test case will fail intermittently.

     *

     * Instead, the test case should be written as

     *

     *      CCDSTestUtils.run(args).assertNormalExit("Hi");

     *

     * EXAMPLES/HOWTO

     *

     * 1. For simple substring matching:

     *

     *      CCDSTestUtils.run(args).assertNormalExit("Hi");

     *      CCDSTestUtils.run(args).assertNormalExit("a", "b", "x");

     *      CCDSTestUtils.run(args).assertAbnormalExit("failure 1", "failure2");

     *

     * 2. For more complex output matching: using Lambda expressions

     *

     *      CCDSTestUtils.run(args)

     *         .assertNormalExit(output -> output.shouldNotContain("this should not be printed");

     *      CCDSTestUtils.run(args)

     *         .assertAbnormalExit(output -> {

     *             output.shouldNotContain("this should not be printed");

     *             output.shouldHaveExitValue(123);

     *           });

     *

     * 3. Chaining several checks:

     *

     *      CCDSTestUtils.run(args)

     *         .assertNormalExit(output -> output.shouldNotContain("this should not be printed")

     *         .assertNormalExit("should have this", "should have that");

     *

     * 4. [Rare use case] if a test sometimes exit normally, and sometimes abnormally:

     *

     *      CCDSTestUtils.run(args)

     *         .ifNormalExit("ths string is printed when exiting with 0")

     *         .ifAbNormalExit("ths string is printed when exiting with 1");

     *

     *    NOTE: you usually don't want to write your test case like this -- it should always

     *    exit with the same exit code. (But I kept this API because some existing test cases

     *    behave this way -- need to revisit).

     */

    public static class Result {

        private final OutputAnalyzer output;

        private final CDSOptions options;

        private final boolean hasMappingFailure;

        private final boolean hasAbnormalExit;

        private final boolean hasNormalExit;

        public Result(CDSOptions opts, OutputAnalyzer out) throws Exception {

            options = opts;

            output = out;

            hasMappingFailure = CDSTestUtils.checkCommonExecExceptions(output);

            hasAbnormalExit   = (!hasMappingFailure) && (output.getExitValue() != 0);

            hasNormalExit     = (!hasMappingFailure) && (output.getExitValue() == 0);

            if (hasNormalExit) {

                    // "-showversion" is always passed in the command-line by the execXXX methods.

                    // During normal exit, we require that the VM to show that sharing was enabled.

                    output.shouldContain("sharing");

                }

            }

        }

        public Result assertNormalExit(Checker checker) throws Exception {

            if (!hasMappingFailure) {

                checker.check(output);

                output.shouldHaveExitValue(0);

            }

            return this;

        }

        public Result assertAbnormalExit(Checker checker) throws Exception {

            if (!hasMappingFailure) {

                checker.check(output);

                output.shouldNotHaveExitValue(0);

            }

            return this;

        }

        public Result ifNormalExit(Checker checker) throws Exception {

            if (hasNormalExit) {

                checker.check(output);

            }

            return this;

        }

        public Result ifAbnormalExit(Checker checker) throws Exception {

            if (hasAbnormalExit) {

                checker.check(output);

            }

            return this;

        }

        public Result ifNoMappingFailure(Checker checker) throws Exception {

            if (!hasMappingFailure) {

                checker.check(output);

            }

            return this;

        }

        public Result assertNormalExit(String... matches) throws Exception {

            if (!hasMappingFailure) {

                checkMatches(output, matches);

                output.shouldHaveExitValue(0);

            }

            return this;

        }

        public Result assertAbnormalExit(String... matches) throws Exception {

            if (!hasMappingFailure) {

                checkMatches(output, matches);

                output.shouldNotHaveExitValue(0);

            }

            return this;

        }

    }

    // Specify this property to copy sdandard output of the child test process to

    // the parent/main stdout of the test.

    // By default such output is logged into a file, and is copied into the main stdout.

    public static final boolean CopyChildStdoutToMainStdout =

        Boolean.valueOf(System.getProperty("test.cds.copy.child.stdout", "true"));

    // This property is passed to child test processes

    public static final String TestTimeoutFactor = System.getProperty("test.timeout.factor", "1.0");

    public static final String UnableToMapMsg =

        "Unable to map shared archive: test did not complete; assumed PASS";

    // Create bootstrap CDS archive,

    // use extra JVM command line args as a prefix.

    // For CDS tests specifying prefix makes more sense than specifying suffix, since

    // normally there are no classes or arguments to classes, just "-version"

    // To specify suffix explicitly use CDSOptions.addSuffix()

    public static OutputAnalyzer createArchive(String... cliPrefix)

        throws Exception {

        return createArchive((new CDSOptions()).addPrefix(cliPrefix));

    }

    // Create bootstrap CDS archive

    public static OutputAnalyzer createArchive(CDSOptions opts)

        throws Exception {

        startNewArchiveName();

        ArrayList<String> cmd = new ArrayList<String>();

        for (String p : opts.prefix) cmd.add(p);

        cmd.add("-Xshare:dump");

        cmd.add("-Xlog:cds,cds+hashtables");

        cmd.add("-XX:+UnlockDiagnosticVMOptions");

        if (opts.archiveName == null)

            opts.archiveName = getDefaultArchiveName();

        cmd.add("-XX:SharedArchiveFile=./" + opts.archiveName);

        for (String s : opts.suffix) cmd.add(s);

        String[] cmdLine = cmd.toArray(new String[cmd.size()]);

        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, cmdLine);

        return executeAndLog(pb, "dump");

    }

    // check result of 'dump-the-archive' operation, that is "-Xshare:dump"

    public static OutputAnalyzer checkDump(OutputAnalyzer output, String... extraMatches)

        throws Exception {

        output.shouldContain("Loading classes to share");

        output.shouldHaveExitValue(0);

        for (String match : extraMatches) {

            output.shouldContain(match);

        }

        return output;

    }

    // A commonly used convenience methods to create an archive and check the results

    // Creates an archive and checks for errors

    public static OutputAnalyzer createArchiveAndCheck(CDSOptions opts)

        throws Exception {

        return checkDump(createArchive(opts));

    }

    public static OutputAnalyzer createArchiveAndCheck(String... cliPrefix)

        throws Exception {

        return checkDump(createArchive(cliPrefix));

    }

    // This method should be used to check the output of child VM for common exceptions.

    // Most of CDS tests deal with child VM processes for creating and using the archive.

    // However exceptions that occur in the child process do not automatically propagate

    // to the parent process. This mechanism aims to improve the propagation

    // of exceptions and common errors.

    // Exception e argument - an exception to be re-thrown if none of the common

    // exceptions match. Pass null if you wish not to re-throw any exception.

    public static boolean checkCommonExecExceptions(OutputAnalyzer output, Exception e)

        throws Exception {

        if (output.getStdout().contains("http://bugreport.java.com/bugreport/crash.jsp")) {

            throw new RuntimeException("Hotspot crashed");

        }

        if (output.getStdout().contains("TEST FAILED")) {

            throw new RuntimeException("Test Failed");

        }

        if (output.getOutput().contains("shared class paths mismatch")) {

//            throw new RuntimeException("shared class paths mismatch");

        }

        if (output.getOutput().contains("Unable to unmap shared space")) {

            throw new RuntimeException("Unable to unmap shared space");

        }

        // Special case -- sometimes Xshare:on fails because it failed to map

        // at given address. This behavior is platform-specific, machine config-specific

        // and can be random (see ASLR).

        if (isUnableToMap(output)) {

            System.out.println(UnableToMapMsg);

            return true;

        }

        if (e != null) {

            throw e;

        }

        return false;

    }

    public static boolean checkCommonExecExceptions(OutputAnalyzer output) throws Exception {

        return checkCommonExecExceptions(output, null);

    }

    // Check the output for indication that mapping of the archive failed.

    // Performance note: this check seems to be rather costly - searching the entire

    // output stream of a child process for multiple strings. However, it is necessary

    // to detect this condition, a failure to map an archive, since this is not a real

    // failure of the test or VM operation, and results in a test being "skipped".

    // Suggestions to improve:

    // 1. VM can designate a special exit code for such condition.

    // 2. VM can print a single distinct string indicating failure to map an archive,

    //    instead of utilizing multiple messages.

    // These are suggestions to improve testibility of the VM. However, implementing them

    // could also improve usability in the field.

    public static boolean isUnableToMap(OutputAnalyzer output) {

        String outStr = output.getOutput();

        if ((output.getExitValue() == 1) && (

            outStr.contains("Unable to reserve shared space at required address") ||

            outStr.contains("Unable to map ReadOnly shared space at required address") ||

            outStr.contains("Unable to map ReadWrite shared space at required address") ||

            outStr.contains("Unable to map MiscData shared space at required address") ||

            outStr.contains("Unable to map MiscCode shared space at required address") ||

            outStr.contains("Unable to map OptionalData shared space at required address") ||

            outStr.contains("Could not allocate metaspace at a compatible address") ||

            outStr.contains("UseSharedSpaces: Unable to allocate region, range is not within java heap") ))

        {

            return true;

        }

        return false;

    }

    public static Result run(String... cliPrefix) throws Exception {

        CDSOptions opts = new CDSOptions();

        opts.setArchiveName(getDefaultArchiveName());

        opts.addPrefix(cliPrefix);

        return new Result(opts, runWithArchive(opts));

    }

    // Execute JVM with CDS archive, specify command line args suffix

    public static OutputAnalyzer runWithArchive(String... cliPrefix)

        throws Exception {

        return runWithArchive( (new CDSOptions())

                               .setArchiveName(getDefaultArchiveName())

                               .addPrefix(cliPrefix) );

    }

    // Execute JVM with CDS archive, specify CDSOptions

    public static OutputAnalyzer runWithArchive(CDSOptions opts)

        throws Exception {

        ArrayList<String> cmd = new ArrayList<String>();

        for (String p : opts.prefix) cmd.add(p);

        cmd.add("-Xshare:" + opts.xShareMode);

        cmd.add("-XX:+UnlockDiagnosticVMOptions");

        cmd.add("-Dtest.timeout.factor=" + TestTimeoutFactor);

        if (opts.archiveName == null)

            opts.archiveName = getDefaultArchiveName();

        cmd.add("-XX:SharedArchiveFile=" + opts.archiveName);

        if (opts.useVersion)

            cmd.add("-version");

        for (String s : opts.suffix) cmd.add(s);

        String[] cmdLine = cmd.toArray(new String[cmd.size()]);

        ProcessBuilder pb = ProcessTools.createJavaProcessBuilder(true, cmdLine);

        return executeAndLog(pb, "exec");

    }

    // A commonly used convenience methods to create an archive and check the results

    // Creates an archive and checks for errors

    public static OutputAnalyzer runWithArchiveAndCheck(CDSOptions opts) throws Exception {

        return checkExec(runWithArchive(opts));

    }

    public static OutputAnalyzer runWithArchiveAndCheck(String... cliPrefix) throws Exception {

        return checkExec(runWithArchive(cliPrefix));

    }

    public static OutputAnalyzer checkExec(OutputAnalyzer output,

                                     String... extraMatches) throws Exception {

        CDSOptions opts = new CDSOptions();

        return checkExec(output, opts, extraMatches);

    }

    // check result of 'exec' operation, that is when JVM is run using the archive

    public static OutputAnalyzer checkExec(OutputAnalyzer output, CDSOptions opts,

                                     String... extraMatches) throws Exception {

        try {

            if ("on".equals(opts.xShareMode)) {

                output.shouldContain("sharing");

            }

            output.shouldHaveExitValue(0);

        } catch (RuntimeException e) {

            checkCommonExecExceptions(output, e);

            return output;

        }

        checkMatches(output, extraMatches);

        return output;

    }

    public static OutputAnalyzer checkExecExpectError(OutputAnalyzer output,

                                             int expectedExitValue,

                                             String... extraMatches) throws Exception {

        if (isUnableToMap(output)) {

            System.out.println(UnableToMapMsg);

            return output;

        }

        output.shouldHaveExitValue(expectedExitValue);

        checkMatches(output, extraMatches);

        return output;

    }

    public static OutputAnalyzer checkMatches(OutputAnalyzer output,

                                              String... matches) throws Exception {

        for (String match : matches) {

            output.shouldContain(match);

        }

        return output;

    }

    // get the file object for the test artifact

    public static File getTestArtifact(String name, boolean checkExistence) {

        File dir = new File(System.getProperty("test.classes", "."));

        File file = new File(dir, name);

        if (checkExistence && !file.exists()) {

            throw new RuntimeException("Cannot find " + file.getPath());

        }

        return file;

    }

    // create file containing the specified class list

    public static File makeClassList(String classes[])

        throws Exception {

        return makeClassList(getTestName() + "-", classes);

    }

    // create file containing the specified class list

    public static File makeClassList(String testCaseName, String classes[])

        throws Exception {

        File classList = getTestArtifact(testCaseName + "test.classlist", false);

        FileOutputStream fos = new FileOutputStream(classList);

        PrintStream ps = new PrintStream(fos);

        addToClassList(ps, classes);

        ps.close();

        fos.close();

        return classList;

    }

    public static void addToClassList(PrintStream ps, String classes[])

        throws IOException

    {

        if (classes != null) {

            for (String s : classes) {

                ps.println(s);

            }

        }

    }

    // Optimization for getting a test name.