1 /*

     2  * Copyright (c) 2000, 2006, Oracle and/or its affiliates. All rights reserved.

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

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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

    21  * questions.

    22  *

    23  */

    24 

    25 package sun.jvm.hotspot.utilities;

    26 

    27 import java.io.*;

    28 import java.util.*;

    29 

    30 import sun.jvm.hotspot.debugger.*;

    31 

    32 /** A utility class encapsulating useful operations on C strings

    33     represented as Addresses */

    34 

    35 public class CStringUtilities {

    36   /** Return the length of a null-terminated ASCII string in the

    37       remote process */

    38   public static int getStringLength(Address addr) {

    39     int i = 0;

    40     while (addr.getCIntegerAt(i, 1, false) != 0) {

    41       i++;

    42     }

    43     return i;

    44   }

    45 

    46   private static String encoding = System.getProperty("file.encoding", "US-ASCII");

    47 

    48   /** Fetch a null-terminated ASCII string from the remote process.

    49       Returns null if the argument is null, otherwise returns a

    50       non-null string (for example, returns an empty string if the

    51       first character fetched is the null terminator). */

    52   public static String getString(Address addr) {

    53     if (addr == null) {

    54       return null;

    55     }

    56 

    57     List data = new ArrayList();

    58     byte val = 0;

    59     long i = 0;

    60     do {

    61       val = (byte) addr.getCIntegerAt(i, 1, false);

    62       if (val != 0) {

    63         data.add(new Byte(val));

    64       }

    65       ++i;

    66     } while (val != 0);

    67 

    68     // Convert to byte[] and from there to String

    69     byte[] bytes = new byte[data.size()];

    70     for (i = 0; i < data.size(); ++i) {

    71       bytes[(int) i] = ((Byte) data.get((int) i)).byteValue();

    72     }

    73     // FIXME: When we switch to use JDK 6 to build SA,

    74     // we can change the following to just return:

    75     // return new String(bytes, Charset.defaultCharset());

    76     try {

    77       return new String(bytes, encoding);

    78     } catch (UnsupportedEncodingException e) {

    79       throw new RuntimeException("Error converting bytes to String using " + encoding + " encoding", e);

    80     }

    81   }

    82 }