--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/utilities/decoder.hpp	Sat Dec 11 13:20:56 2010 -0500
@@ -0,0 +1,102 @@
+/*
+ * Copyright (c) 1997, 2010, 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.
+ *
+ */
+
+
+#ifndef __DECODER_HPP
+#define __DECODER_HPP
+
+#include "memory/allocation.hpp"
+
+#ifdef _WINDOWS
+#include <windows.h>
+#include <imagehlp.h>
+
+// functions needed for decoding symbols
+typedef DWORD (WINAPI *pfn_SymSetOptions)(DWORD);
+typedef BOOL  (WINAPI *pfn_SymInitialize)(HANDLE, PCTSTR, BOOL);
+typedef BOOL  (WINAPI *pfn_SymGetSymFromAddr64)(HANDLE, DWORD64, PDWORD64, PIMAGEHLP_SYMBOL64);
+typedef DWORD (WINAPI *pfn_UndecorateSymbolName)(const char*, char*, DWORD, DWORD);
+
+#else
+
+class ElfFile;
+
+#endif // _WINDOWS
+
+
+class Decoder: public StackObj {
+
+ public:
+  // status code for decoding native C frame
+  enum decoder_status {
+         no_error,             // successfully decoded frames
+         out_of_memory,        // out of memory
+         file_invalid,         // invalid elf file
+         file_not_found,       // could not found symbol file (on windows), such as jvm.pdb or jvm.map
+         helper_not_found,     // could not load dbghelp.dll (Windows only)
+         helper_func_error,    // decoding functions not found (Windows only)
+         helper_init_error,    // SymInitialize failed (Windows only)
+         symbol_not_found      // could not find the symbol
+  };
+
+ public:
+  Decoder() { initialize(); };
+  ~Decoder() { uninitialize(); };
+
+  static bool can_decode_C_frame_in_vm();
+
+  static void initialize();
+  static void uninitialize();
+
+#ifdef _WINDOWS
+  static decoder_status    decode(address addr, char *buf, int buflen, int *offset);
+#else
+  static decoder_status    decode(address addr, const char* filepath, char *buf, int buflen, int *offset);
+#endif
+
+  static bool              demangle(const char* symbol, char *buf, int buflen);
+
+  static decoder_status    get_status() { return _decoder_status; };
+
+#ifndef _WINDOWS
+ private:
+  static ElfFile*         get_elf_file(const char* filepath);
+#endif // _WINDOWS
+
+
+ private:
+  static decoder_status     _decoder_status;
+  static bool               _initialized;
+
+#ifdef _WINDOWS
+  static HMODULE                   _dbghelp_handle;
+  static bool                      _can_decode_in_vm;
+  static pfn_SymGetSymFromAddr64   _pfnSymGetSymFromAddr64;
+  static pfn_UndecorateSymbolName  _pfnUndecorateSymbolName;
+#else
+  static ElfFile*                  _opened_elf_files;
+#endif // _WINDOWS
+};
+
+#endif // __DECODER_HPP