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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.  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 com.sun.servicetag;

import java.io.*;

import java.util.ArrayList;

import java.util.Date;

import java.util.HashSet;

import java.util.List;

import java.util.Properties;

import java.util.Set;

import static com.sun.servicetag.Util.*;

import static com.sun.servicetag.RegistrationDocument.*;

/**

 * A service tag registry is a XML-based registry containing

 * the list of {@link ServiceTag service tags} installed in the system.

 * The {@code Registry} class provides interfaces

 * to add, remove, update, and get a service tag from a service tag

 * registry.

 * This {@code Registry} class may not be supported

 * on all systems. The {@link #isSupported} method

 * can be called to determine if it is supported.

 * <p>

 * A registry may implement restrictions to only allow certain users

 * to {@link #updateServiceTag update} and

 * to {@link #removeServiceTag remove} a service tag record. Typically,

 * only the owner of the service tag, the owner of the registry

 * and superuser are authorized to update or remove a service tag in

 * the registry.

 *

 * @see <a href="https://sn-tools.central.sun.com/twiki/bin/view/ServiceTags/ServiceTagDevGuideHelper">

 * Service Tag User Guide</a>

 */

public class Registry {

    private static final String STCLIENT_SOLARIS = "/usr/bin/stclient";

    private static final String STCLIENT_LINUX = "/opt/sun/servicetag/bin/stclient";

    // stclient exit value (see sthelper.h)

    private static final int ST_ERR_NOT_AUTH = 245;

    private static final int ST_ERR_REC_NOT_FOUND = 225;

    // The stclient output has to be an exported interface

    private static final String INSTANCE_URN_DESC = "Product instance URN=";

    private static boolean initialized = false;

    private static File stclient = null;

    private static String stclientPath = null;

    private static Registry registry = new Registry();

    // System properties for testing

    private static String SVCTAG_STCLIENT_CMD = "servicetag.stclient.cmd";

    private static String SVCTAG_STHELPER_SUPPORTED = "servicetag.sthelper.supported";

    private Registry() {

    }

    private synchronized static String getSTclient() {

        if (!initialized) {

            // Initialization to determine the platform's stclient pathname

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

            if (os.equals("SunOS")) {

                stclient = new File(STCLIENT_SOLARIS);

            } else if (os.equals("Linux")) {

                stclient = new File(STCLIENT_LINUX);

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

                stclient = getWindowsStClientFile();

            } else {

                if (isVerbose()) {

                    System.out.println("Running on unsupported platform");

                }

            }

            initialized = true;

        }

        boolean supportsHelperClass = true; // default

        if (System.getProperty(SVCTAG_STHELPER_SUPPORTED) != null) {

            // the system property always overrides the default setting

            supportsHelperClass = Boolean.getBoolean(SVCTAG_STHELPER_SUPPORTED);

        }

        if (!supportsHelperClass) {

            // disable system registry

            return null;

        }

        // This is only used for testing

        String path = System.getProperty(SVCTAG_STCLIENT_CMD);

        if (path != null) {

            return path;

        }

        // com.sun.servicetag package has to be compiled with JDK 5 as well

        // JDK 5 doesn't support the File.canExecute() method.

        // Risk not checking isExecute() for the stclient command is very low.

        if (stclientPath == null && stclient != null && stclient.exists()) {

            stclientPath = stclient.getAbsolutePath();

        }

        return stclientPath;

    }

    /**

     * Returns the system service tag registry. The {@code Registry} class

     * may not be supported on some platforms; use the {@link #isSupported}

     * method to determine if it is supported.

     *

     * @return the {@code Registry} object for the system service tag registry.

     *

     * @throws UnsupportedOperationException if the {@code Registry} class is

     * not supported.

     */

    public static Registry getSystemRegistry() {

        if (isSupported()) {

            return registry;

        } else {

            throw new UnsupportedOperationException("Registry class is not supported");

        }

    }

    /**

     * Returns {@code true} if the {@code Registry} class is supported on this system.

     *

     * @return {@code true} if the {@code Registry} class is supported;

     * otherwise, return {@code false}.

     */

    public static synchronized boolean isSupported() {

        return getSTclient() != null;

    }

    private static List<String> getCommandList() {

        // Set up the arguments to call stclient

        List<String> command = new ArrayList<String>();

        if (System.getProperty(SVCTAG_STCLIENT_CMD) != null) {

            // This is for jtreg testing use. This will be set to something

            // like:

            // $JAVA_HOME/bin/java -cp $TEST_DIR \

            //    -Dstclient.registry.path=$TEST_DIR/registry.xml \

            //    SvcTagClient

            //

            // On Windows, the JAVA_HOME and TEST_DIR path could contain

            // space e.g. c:\Program Files\Java\jdk1.6.0_05\bin\java.

            // The SVCTAG_STCLIENT_CMD must be set with a list of

            // space-separated parameters.  If a parameter contains spaces,

            // it must be quoted with '"'.

            String cmd = getSTclient();

            int len = cmd.length();

            int i = 0;

            while (i < len) {

                char separator = ' ';

                if (cmd.charAt(i) == '"') {

                    separator = '"';

                    i++;

                }

                // look for the separator or matched the closing '"'

                int j;

                for (j = i+1; j < len; j++) {

                    if (cmd.charAt(j) == separator) {

                        break;

                    }

                }

                if (i == j-1) {

                    // add an empty parameter

                    command.add("\"\"");

                } else {

                    // double quotes and space are not included

                    command.add(cmd.substring(i,j));

                }

                // skip spaces

                for (i = j+1; i < len; i++) {

                    if (!Character.isSpaceChar(cmd.charAt(i))) {

                        break;

                    }

                }

            }

            if (isVerbose()) {

                System.out.println("Command list:");

                for (String s : command) {

                    System.out.println(s);

                }

            }

        } else {

            command.add(getSTclient());

        }

        return command;

    }

    // Returns null if the service tag record not found;

    // or throw UnauthorizedAccessException or IOException

    // based on the exitValue.

    private static ServiceTag checkReturnError(int exitValue,

                                               String output,

                                               ServiceTag st) throws IOException {

        switch (exitValue) {

            case ST_ERR_REC_NOT_FOUND:

                return null;

            case ST_ERR_NOT_AUTH:

                if (st != null) {

                    throw new UnauthorizedAccessException(

                        "Not authorized to access " + st.getInstanceURN() +

                        " installer_uid=" + st.getInstallerUID());

                } else  {

                    throw new UnauthorizedAccessException(

                        "Not authorized:" + output);

                }

            default:

                throw new IOException("stclient exits with error" +

                     " (" + exitValue + ")\n" + output);

        }

    }

    /**

     * Adds a service tag to this registry.

     * If the given service tag has an empty <tt>instance_urn</tt>,

     * this helper class will generate a URN and place it in the

     * copy of the service tag in this registry.

     * This method will return the {@code ServiceTag} representing

     * the service tag entry to this registry.

     *

     * @param st {@code ServiceTag} object

     * @return a {@code ServiceTag} object representing the service tag

     *         entry to this registry.

     *

     * @throws IllegalArgumentException if a service tag of the same

     * <tt>instance_urn</tt> already exists in this registry.

     *

     * @throws java.io.IOException if an I/O error occurs in this operation.

     */

    public ServiceTag addServiceTag(ServiceTag st) throws IOException {

        List<String> command = getCommandList();

        command.add("-a");

        if (st.getInstanceURN().length() > 0) {

            ServiceTag sysSvcTag = getServiceTag(st.getInstanceURN());

            if (sysSvcTag != null) {

                throw new IllegalArgumentException("Instance_urn = " +

                    st.getInstanceURN() + " already exists");

            }

            command.add("-i");

            command.add(st.getInstanceURN());

        }

        command.add("-p");

        command.add(st.getProductName());

        command.add("-e");

        command.add(st.getProductVersion());

        command.add("-t");

        command.add(st.getProductURN());

        if (st.getProductParentURN().length() > 0) {

            command.add("-F");

            command.add(st.getProductParentURN());

        }

        command.add("-P");

        command.add(st.getProductParent());

        if (st.getProductDefinedInstanceID().length() > 0) {

            command.add("-I");

            command.add(st.getProductDefinedInstanceID());

        }

        command.add("-m");

        command.add(st.getProductVendor());

        command.add("-A");

        command.add(st.getPlatformArch());

        command.add("-z");

        command.add(st.getContainer());

        command.add("-S");

        command.add(st.getSource());

        BufferedReader in = null;

        try {

            ProcessBuilder pb = new ProcessBuilder(command);

            Process p = pb.start();

            String output = commandOutput(p);

            if (isVerbose()) {

                System.out.println("Output from stclient -a command:");

                System.out.println(output);

            }

            String urn = "";

            if (p.exitValue() == 0) {

                // Obtain the instance urn from the stclient output

                in = new BufferedReader(new StringReader(output));

                String line = null;

                while ((line = in.readLine()) != null) {

                    line = line.trim();

                    if (line.startsWith(INSTANCE_URN_DESC)) {

                        urn = line.substring(INSTANCE_URN_DESC.length());

                        break;

                    }

                }

                if (urn.length() == 0) {

                    throw new IOException("Error in creating service tag:\n" +

                        output);

                }

                return getServiceTag(urn);

            } else {

                return checkReturnError(p.exitValue(), output, st);

            }

        } finally {

            if (in != null) {

                in.close();

            }

        }

    }

    /**

     * Removes a service tag of the given <tt>instance_urn</tt> from this

     * registry.

     *

     * @param instanceURN the <tt>instance_urn</tt> of the service tag

     *        to be removed.

     *

     * @return the {@code ServiceTag} object removed from this registry;

     * or {@code null} if the service tag does not exist in this registry.

     *

     * @throws UnauthorizedAccessException if the user is not authorized to

     * remove the service tag of the given <tt>instance_urn</tt>

     * from this registry.

     *

     * @throws java.io.IOException if an I/O error occurs in this operation.

     */

    public ServiceTag removeServiceTag(String instanceURN) throws IOException {

        ServiceTag st = getServiceTag(instanceURN);

        if (st == null) {

            return null;

        }

        List<String> command = getCommandList();

        command.add("-d");

        command.add("-i");

        command.add(instanceURN);

        ProcessBuilder pb = new ProcessBuilder(command);

        Process p = pb.start();

        String output = commandOutput(p);

        if (isVerbose()) {

            System.out.println("Output from stclient -d command:");

            System.out.println(output);

        }

        if (p.exitValue() == 0) {

            return st;

        } else {

            return checkReturnError(p.exitValue(), output, st);

        }

    }

    /**

     * Updates the <tt>product_defined_instance_id</tt> in the service tag

     * of the specified <tt>instance_urn</tt> in this registry.

     *

     * @param instanceURN the <tt>instance_urn</tt> of the service tag to be updated.

     * @param productDefinedInstanceID the value of the

     * <tt>product_defined_instance_id</tt> to be set.

     *

     * @return the updated {@code ServiceTag} object;

     * or {@code null} if the service tag does not exist in this

     * registry.

     *

     * @throws UnauthorizedAccessException if the user is not authorized to

     * update the service tag from this registry.

     *

     * @throws IOException if an I/O error occurs in this operation.

     */

    public ServiceTag updateServiceTag(String instanceURN,

                                       String productDefinedInstanceID)

            throws IOException {

        ServiceTag svcTag = getServiceTag(instanceURN);

        if (svcTag == null) {

            return null;

        }

        List<String> command = getCommandList();

        command.add("-u");

        command.add("-i");

        command.add(instanceURN);

        command.add("-I");

        if (productDefinedInstanceID.length() > 0) {

            command.add(productDefinedInstanceID);

        } else {

            command.add("\"\"");

        }

        ProcessBuilder pb = new ProcessBuilder(command);

        Process p = pb.start();

        String output = commandOutput(p);

        if (isVerbose()) {

            System.out.println("Output from stclient -u command:");

            System.out.println(output);

        }

        if (p.exitValue() == 0) {

            return getServiceTag(instanceURN);

        } else {

            return checkReturnError(p.exitValue(), output, svcTag);

        }

    }

    /**

     * Returns a {@code ServiceTag} object of the given  <tt>instance_urn</tt>

     * in this registry.

     *

     * @param instanceURN the  <tt>instance_urn</tt> of the service tag

     * @return a {@code ServiceTag} object of the given <tt>instance_urn</tt>

     * in this registry; or {@code null} if not found.

     *

     * @throws java.io.IOException if an I/O error occurs in this operation.

     */

    public ServiceTag getServiceTag(String instanceURN) throws IOException {

        if (instanceURN == null) {

            throw new NullPointerException("instanceURN is null");

        }

        List<String> command = getCommandList();

        command.add("-g");

        command.add("-i");

        command.add(instanceURN);

        ProcessBuilder pb = new ProcessBuilder(command);

        Process p = pb.start();

        String output = commandOutput(p);

        if (isVerbose()) {

            System.out.println("Output from stclient -g command:");

            System.out.println(output);

        }

        if (p.exitValue() == 0) {

            return parseServiceTag(output);

        } else {

            return checkReturnError(p.exitValue(), output, null);

        }

    }

    private ServiceTag parseServiceTag(String output) throws IOException {

        BufferedReader in = null;

        try {

            Properties props = new Properties();

            // parse the service tag output from stclient

            in = new BufferedReader(new StringReader(output));

            String line = null;

            while ((line = in.readLine()) != null) {

                if ((line = line.trim()).length() > 0) {

                    String[] ss = line.trim().split("=", 2);

                    if (ss.length == 2) {

                        props.setProperty(ss[0].trim(), ss[1].trim());

                    } else {

                        props.setProperty(ss[0].trim(), "");

                    }

                }

            }

            String urn = props.getProperty(ST_NODE_INSTANCE_URN);

            String productName = props.getProperty(ST_NODE_PRODUCT_NAME);

            String productVersion = props.getProperty(ST_NODE_PRODUCT_VERSION);

            String productURN = props.getProperty(ST_NODE_PRODUCT_URN);

            String productParent = props.getProperty(ST_NODE_PRODUCT_PARENT);

            String productParentURN = props.getProperty(ST_NODE_PRODUCT_PARENT_URN);

            String productDefinedInstanceID =

                props.getProperty(ST_NODE_PRODUCT_DEFINED_INST_ID);

            String productVendor = props.getProperty(ST_NODE_PRODUCT_VENDOR);

            String platformArch = props.getProperty(ST_NODE_PLATFORM_ARCH);

            String container = props.getProperty(ST_NODE_CONTAINER);

            String source = props.getProperty(ST_NODE_SOURCE);

            int installerUID =

                Util.getIntValue(props.getProperty(ST_NODE_INSTALLER_UID));

            Date timestamp =

                Util.parseTimestamp(props.getProperty(ST_NODE_TIMESTAMP));

            return new ServiceTag(urn,

                                  productName,

                                  productVersion,

                                  productURN,

                                  productParent,

                                  productParentURN,

                                  productDefinedInstanceID,

                                  productVendor,

                                  platformArch,

                                  container,

                                  source,

                                  installerUID,

                                  timestamp);

        } finally {

            if (in != null) {

                in.close();

            }

        }

    }

    /**

     * Returns the service tags of the specified

     * <tt>product_urn</tt> in this registry.

     *

     * @param productURN the  <tt>product_urn</tt> to look up

     * @return a {@code Set} of {@code ServiceTag} objects

     * of the specified <tt>product_urn</tt> in this registry.

     *

     * @throws java.io.IOException if an I/O error occurs in this operation.

     */

    public Set<ServiceTag> findServiceTags(String productURN) throws IOException {

        if (productURN == null) {

            throw new NullPointerException("productURN is null");

        }

        List<String> command = getCommandList();

        command.add("-f");

        command.add("-t");