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 * Project: S.Ha.R.K.
 * Coordinators:
 *   Giorgio Buttazzo    <>
 *   Paolo Gai           <>
 * Authors     :
 *   Paolo Gai           <>
 *   Massimiliano Giorgi <>
 *   Luca Abeni          <>
 *   (see the web pages for full authors list)
 * ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy)

 CVS :        $Id: npp.h,v 1.1 2005-02-25 10:45:36 pj Exp $

 File:        $File$
 Revision:    $Revision: 1.1 $
 Last update: $Date: 2005-02-25 10:45:36 $

 This file contains the Non Preemptive Protocol (NPP)

   NPP (Non Preemptive Protocol)

 Resource Models Accepted:

   This module implement the Non Preemptive Protocol.
   When a task aquire a critical section, it become non-preemptable.

   A NPP mutex is created passing the NPP_mutexattr structure to mutex_init.

 Exceptions raised:
     This exception is raised when a task ends and it owns one or more

 Restrictions & special features:
   - This module is NOT Posix compliant
   - This module can manage any number of NPP mutexes.
   - if a task uses a NPP mutex, it can use only this type of mutex.
   - If a task ends (because it reaches the end of the body or because it
     is killed by someone) and it owns some mutex, an exception is raised.
   - if a mutex unlock is called on a mutex not previously
     locked or previously locked by another task an error is returned
   - A NPP mutex can be statically allocated. To do this, the init function
     have to define a macro that puts this information in the mutex
     descriptor: mutexlevel = <NPP resource level>; opt = NULL;
     for example, if the NPP module is registered at level 1, the macro is
     #define MUTEX_INITIALIZER {1,(void *)NULL}


 * Copyright (C) 2000 Paolo Gai
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * GNU General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#ifndef __NPP_H__
#define __NPP_H__

#include <arch/sys/cdefs.h>


void NPP_register_module(void);