nes-proj/os/sys/mutex.c
2017-12-09 17:09:57 +00:00

71 lines
2.5 KiB
C

/*
* Copyright (c) 2017, George Oikonomou - http://www.spd.gr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*---------------------------------------------------------------------------*/
/**
* \addtogroup mutex
* @{
*/
/*---------------------------------------------------------------------------*/
#include "contiki.h"
#include "sys/mutex.h"
#include "sys/critical.h"
#include <stdint.h>
#include <stdbool.h>
/*---------------------------------------------------------------------------*/
bool
mutex_generic_try_lock(volatile mutex_t *mutex)
{
bool success = false;
int_master_status_t status = critical_enter();
if(*mutex == MUTEX_STATUS_UNLOCKED) {
*mutex = MUTEX_STATUS_LOCKED;
success = true;
}
critical_exit(status);
return success;
}
/*---------------------------------------------------------------------------*/
void
mutex_generic_unlock(volatile mutex_t *mutex)
{
int_master_status_t status = critical_enter();
*mutex = MUTEX_STATUS_UNLOCKED;
critical_exit(status);
}
/*---------------------------------------------------------------------------*/
/** @} */