/* VMSecurityManager.java -- Reference implementation of VM hooks for security
   Copyright (C) 1998, 2002 Free Software Foundation
 
This file is part of GNU Classpath.
 
GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
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any later version.
 
GNU Classpath is distributed in the hope that it will be useful, but
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
General Public License for more details.
 
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along with GNU Classpath; see the file COPYING.  If not, write to the
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02111-1307 USA.
 
Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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this exception to your version of the library, but you are not
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package java.lang;

/**
 * VMSecurityManager is a helper class for SecurityManager the VM must
 * implement.
 *
 * @author John Keiser
 * @author Eric Blake <ebb9@email.byu.edu>
 */
final class VMSecurityManager
{
  /**
   * Get a list of all the classes currently executing methods on the
   * Java stack.  getClassContext()[0] is the currently executing method, ie.
   * the method which called SecurityManager.getClassContext().  (Hint: you
   * may need to pop off one or more frames: don't include SecurityManager
   * or VMSecurityManager.getClassContext in your result. Also, be sure that
   * you correctly handle the context if SecurityManager.getClassContext
   * was invoked by reflection).
   *
   * @return an array of the declaring classes of each stack frame
   */
  static native Class[] getClassContext();

  /**
   * Get the current ClassLoader. This is the first non-null class loader
   * on the stack, if one exists, stopping either at the end of the stack
   * or the first instance of a PrivilegedAction. In other words, this call
   * automatically unwinds past all classes loaded by the bootstrap loader,
   * where getClassLoader() returns null, to get to the user class that
   * really invoked the call that needs a classloader.
   *
   * @return the current ClassLoader
   */
  static native ClassLoader currentClassLoader();
}