src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/CStringUtilities.java
changeset 47216 71c04702a3d5
parent 35217 ce4b5303a813
child 50560 dafb2cc6ba32
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/utilities/CStringUtilities.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,82 @@
+/*
+ * Copyright (c) 2000, 2006, 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
+ * questions.
+ *
+ */
+
+package sun.jvm.hotspot.utilities;
+
+import java.io.*;
+import java.util.*;
+
+import sun.jvm.hotspot.debugger.*;
+
+/** A utility class encapsulating useful operations on C strings
+    represented as Addresses */
+
+public class CStringUtilities {
+  /** Return the length of a null-terminated ASCII string in the
+      remote process */
+  public static int getStringLength(Address addr) {
+    int i = 0;
+    while (addr.getCIntegerAt(i, 1, false) != 0) {
+      i++;
+    }
+    return i;
+  }
+
+  private static String encoding = System.getProperty("file.encoding", "US-ASCII");
+
+  /** Fetch a null-terminated ASCII string from the remote process.
+      Returns null if the argument is null, otherwise returns a
+      non-null string (for example, returns an empty string if the
+      first character fetched is the null terminator). */
+  public static String getString(Address addr) {
+    if (addr == null) {
+      return null;
+    }
+
+    List data = new ArrayList();
+    byte val = 0;
+    long i = 0;
+    do {
+      val = (byte) addr.getCIntegerAt(i, 1, false);
+      if (val != 0) {
+        data.add(new Byte(val));
+      }
+      ++i;
+    } while (val != 0);
+
+    // Convert to byte[] and from there to String
+    byte[] bytes = new byte[data.size()];
+    for (i = 0; i < data.size(); ++i) {
+      bytes[(int) i] = ((Byte) data.get((int) i)).byteValue();
+    }
+    // FIXME: When we switch to use JDK 6 to build SA,
+    // we can change the following to just return:
+    // return new String(bytes, Charset.defaultCharset());
+    try {
+      return new String(bytes, encoding);
+    } catch (UnsupportedEncodingException e) {
+      throw new RuntimeException("Error converting bytes to String using " + encoding + " encoding", e);
+    }
+  }
+}