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

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 * 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 jdk.jfr.internal.dcmd;

import java.io.FileNotFoundException;

import java.io.IOException;

import java.nio.file.Files;

import java.nio.file.InvalidPathException;

import java.nio.file.Path;

import java.nio.file.Paths;

import java.text.ParseException;

import java.time.Duration;

import java.util.Arrays;

import java.util.HashMap;

import java.util.Map;

import jdk.jfr.FlightRecorder;

import jdk.jfr.Recording;

import jdk.jfr.internal.JVM;

import jdk.jfr.internal.LogLevel;

import jdk.jfr.internal.LogTag;

import jdk.jfr.internal.Logger;

import jdk.jfr.internal.OldObjectSample;

import jdk.jfr.internal.PrivateAccess;

import jdk.jfr.internal.SecuritySupport.SafePath;

import jdk.jfr.internal.Type;

import jdk.jfr.internal.jfc.JFC;

/**

 * JFR.start

 *

 */

//Instantiated by native

final class DCmdStart extends AbstractDCmd {

    /**

     * Execute JFR.start.

     *

     * @param name optional name that can be used to identify recording.

     * @param settings names of settings files to use, i.e. "default" or

     *        "default.jfc".

     * @param delay delay before recording is started, in nanoseconds. Must be

     *        at least 1 second.

     * @param duration duration of the recording, in nanoseconds. Must be at

     *        least 1 second.

     * @param disk if recording should be persisted to disk

     * @param path file path where recording data should be written

     * @param maxAge how long recording data should be kept in the disk

     *        repository, or <code>0</code> if no limit should be set.

     *

     * @param maxSize the minimum amount data to keep in the disk repository

     *        before it is discarded, or <code>0</code> if no limit should be

     *        set.

     *

     * @param dumpOnExit if recording should dump on exit

     *

     * @return result output

     *

     * @throws DCmdException if recording could not be started

     */

    @SuppressWarnings("resource")

    public String execute(String name, String[] settings, Long delay, Long duration, Boolean disk, String path, Long maxAge, Long maxSize, Boolean dumpOnExit, Boolean pathToGcRoots) throws DCmdException {

        if (Logger.shouldLog(LogTag.JFR_DCMD, LogLevel.DEBUG)) {

            Logger.log(LogTag.JFR_DCMD, LogLevel.DEBUG, "Executing DCmdStart: name=" + name +

                    ", settings=" + (settings != null ? Arrays.asList(settings) : "(none)") +

                    ", delay=" + delay +

                    ", duration=" + duration +

                    ", disk=" + disk+

                    ", filename=" + path +

                    ", maxage=" + maxAge +

                    ", maxsize=" + maxSize +

                    ", dumponexit =" + dumpOnExit +

                    ", path-to-gc-roots=" + pathToGcRoots);

        }

        if (name != null) {

            try {

                Integer.parseInt(name);

                throw new DCmdException("Name of recording can't be numeric");

            } catch (NumberFormatException nfe) {

                // ok, can't be mixed up with name

            }

        }

        if (duration == null && Boolean.FALSE.equals(dumpOnExit) && path != null) {

            throw new DCmdException("Filename can only be set for a time bound recording or if dumponexit=true. Set duration/dumponexit or omit filename.");

        }

        if (settings.length == 1 && settings[0].length() == 0) {

            throw new DCmdException("No settings specified. Use settings=none to start without any settings");

        }

        Map<String, String> s = new HashMap<>();

        for (String configName : settings) {

            try {

                s.putAll(JFC.createKnown(configName).getSettings());

            } catch(FileNotFoundException e) {

                throw new DCmdException("Could not find settings file'" + configName + "'", e);

            } catch (IOException | ParseException e) {

                throw new DCmdException("Could not parse settings file '" + settings[0] + "'", e);

            }

        }

        OldObjectSample.updateSettingPathToGcRoots(s, pathToGcRoots);

        if (duration != null) {

            if (duration < 1000L * 1000L * 1000L) {

                // to avoid typo, duration below 1s makes no sense

                throw new DCmdException("Could not start recording, duration must be at least 1 second.");

            }

        }

        if (delay != null) {

            if (delay < 1000L * 1000L * 1000) {

                // to avoid typo, delay shorter than 1s makes no sense.

                throw new DCmdException("Could not start recording, delay must be at least 1 second.");

            }

        }

        if (!FlightRecorder.isInitialized() && delay == null) {

            initializeWithForcedInstrumentation(s);

        }

        Recording recording = new Recording();

        if (name != null) {

            recording.setName(name);

        }

        if (disk != null) {

            recording.setToDisk(disk.booleanValue());

        }

        recording.setSettings(s);

        SafePath safePath = null;

        if (path != null) {

            try {

                if (dumpOnExit == null) {

                    // default to dumponexit=true if user specified filename

                    dumpOnExit = Boolean.TRUE;

                }

                Path p = Paths.get(path);

                if (Files.isDirectory(p) && Boolean.TRUE.equals(dumpOnExit)) {

                    // Decide destination filename at dump time

                    // Purposely avoid generating filename in Recording#setDestination due to

                    // security concerns

                    PrivateAccess.getInstance().getPlatformRecording(recording).setDumpOnExitDirectory(new SafePath(p));

                } else {

                    safePath = resolvePath(recording, path);

                    recording.setDestination(safePath.toPath());

                }

            } catch (IOException | InvalidPathException e) {

                recording.close();

                throw new DCmdException("Could not start recording, not able to write to file %s. %s ", path, e.getMessage());

            }

        }

        if (maxAge != null) {

            recording.setMaxAge(Duration.ofNanos(maxAge));

        }

        if (maxSize != null) {

            recording.setMaxSize(maxSize);

        }

        if (duration != null) {

            recording.setDuration(Duration.ofNanos(duration));

        }

        if (dumpOnExit != null) {

            recording.setDumpOnExit(dumpOnExit);

        }

        if (delay != null) {

            Duration dDelay = Duration.ofNanos(delay);

            recording.scheduleStart(dDelay);

            print("Recording " + recording.getId() + " scheduled to start in ");

            printTimespan(dDelay, " ");

            print(".");

        } else {

            recording.start();

            print("Started recording " + recording.getId() + ".");

        }

        if (recording.isToDisk() && duration == null && maxAge == null && maxSize == null) {

            print(" No limit specified, using maxsize=250MB as default.");

            recording.setMaxSize(250*1024L*1024L);

        }

        if (safePath != null && duration != null) {

            println(" The result will be written to:");

            println();

            printPath(safePath);

        } else {

            println();

            println();

            String cmd = duration == null ? "dump" : "stop";

            String fileOption = path == null ? "filename=FILEPATH " : "";

            String recordingspecifier = "name=" + recording.getId();

            // if user supplied a name, use it.

            if (name != null) {

                recordingspecifier = "name=" + quoteIfNeeded(name);

            }

            print("Use jcmd " + getPid() + " JFR." + cmd + " " + recordingspecifier + " " + fileOption + "to copy recording data to file.");

            println();

        }

        return getResult();

    }

    // Instruments JDK-events on class load to reduce startup time

    private void initializeWithForcedInstrumentation(Map<String, String> settings) {

        if (!hasJDKEvents(settings)) {

            return;

        }

        JVM jvm = JVM.getJVM();

        try {

           jvm.setForceInstrumentation(true);

            FlightRecorder.getFlightRecorder();

        } finally {

           jvm.setForceInstrumentation(false);

        }

    }

    private boolean hasJDKEvents(Map<String, String> settings) {

        String[] eventNames = new String[7];

        eventNames[0] = "FileRead";

        eventNames[1] = "FileWrite";

        eventNames[2] = "SocketRead";

        eventNames[3] = "SocketWrite";

        eventNames[4] = "JavaErrorThrow";

        eventNames[5] = "JavaExceptionThrow";

        eventNames[6] = "FileForce";

        for (String eventName : eventNames) {

            if ("true".equals(settings.get(Type.EVENT_NAME_PREFIX + eventName + "#enabled"))) {

                return true;

            }

        }

        return false;

    }

}