#ifndef __ALT_SEM_H__
#define __ALT_SEM_H__

/******************************************************************************
*                                                                             *
* License Agreement                                                           *
*                                                                             *
* Copyright (c) 2003 Altera Corporation, San Jose, California, USA.           *
* All rights reserved.                                                        *
*                                                                             *
* Permission is hereby granted, free of charge, to any person obtaining a     *
* copy of this software and associated documentation files (the "Software"),  *
* to deal in the Software without restriction, including without limitation   *
* the rights to use, copy, modify, merge, publish, distribute, sublicense,    *
* and/or sell copies of the Software, and to permit persons to whom the       *
* Software is furnished to do so, subject to the following conditions:        *
*                                                                             *
* The above copyright notice and this permission notice shall be included in  *
* all copies or substantial portions of the Software.                         *
*                                                                             *
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR  *
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,    *
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE *
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER      *
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING     *
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER         *
* DEALINGS IN THE SOFTWARE.                                                   *
*                                                                             *
* This agreement shall be governed in all respects by the laws of the State   *
* of California and by the laws of the United States of America.              *
*                                                                             *
******************************************************************************/

/*
 * This header provides macro definitions that can be used to create and use
 * semaphores. These macros can be used in both a uC/OS-II based environment,
 * and a single threaded HAL based environment.
 *
 * The motivation for these macros is to allow code to be developed which is
 * thread safe under uC/OS-II, but incurs no additional overhead when used in a
 * single threaded HAL environment.  
 *
 * In the case of a single threaded HAL environment, they compile to 
 * "do nothing" directives, which ensures they do not contribute to the final
 * executable. The macro definitions used in that case are supplied with the
 * HAL.
 *
 * The following macros are available:
 *
 * ALT_SEM        - Create a semaphore instance.
 * ALT_EXTERN_SEM - Create a reference to an external semaphore instance.
 * ALT_STATIC_SEM - Create a static semaphore instance.
 * ALT_SEM_CREATE - Initialise a semaphore.
 * ALT_SEM_PEND   - Pend on a semaphore.
 * ALT_SEM_POST   - Increment a semaphore.
 *
 * Input arguments and return codes are all consistant with the equivalent
 * uC/OS-II function.
 *
 * It's important to be careful in the use of the macros: ALT_SEM, 
 * ALT_EXTERN_SEM, and ALT_STATIC_SEM. In these three cases the semi-colon is
 * included in the macro definition; so, for example, you should use:
 *
 * ALT_SEM(mysem)
 *
 * not:
 *
 * ALT_SEM(mysem);
 *
 * The inclusion of the semi-colon has been necessary to ensure the macros can
 * compile with no warnings when used in a single threaded HAL environment.
 *
 */ 

#include "priv/alt_sem_ucosii.h"

#define ALT_SEM(sem) OS_EVENT* sem;
#define ALT_EXTERN_SEM(sem) extern OS_EVENT* sem;
#define ALT_STATIC_SEM(sem) static OS_EVENT* sem;

#define ALT_SEM_CREATE(sem, value) alt_sem_create (sem, value)
#define ALT_SEM_PEND(sem, timeout) alt_sem_pend (sem, timeout)
#define ALT_SEM_POST(sem) OSSemPost (sem)

#endif /* __ALT_SEM_H__ */
