Contiki-NG
mutex.c
1 /*
2  * Copyright (c) 2017, George Oikonomou - http://www.spd.gr
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright
10  * notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  * notice, this list of conditions and the following disclaimer in the
13  * documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the copyright holder nor the names of its
15  * contributors may be used to endorse or promote products derived
16  * from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
25  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
27  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
29  * OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*---------------------------------------------------------------------------*/
32 /**
33  * \addtogroup mutex
34  * @{
35  */
36 /*---------------------------------------------------------------------------*/
37 #include "contiki.h"
38 #include "sys/mutex.h"
39 #include "sys/critical.h"
40 
41 #include <stdint.h>
42 #include <stdbool.h>
43 /*---------------------------------------------------------------------------*/
44 bool
45 mutex_generic_try_lock(volatile mutex_t *mutex)
46 {
47  bool success = false;
49 
50  if(*mutex == MUTEX_STATUS_UNLOCKED) {
51  *mutex = MUTEX_STATUS_LOCKED;
52  success = true;
53  }
54 
55  critical_exit(status);
56 
57  return success;
58 }
59 /*---------------------------------------------------------------------------*/
60 void
61 mutex_generic_unlock(volatile mutex_t *mutex)
62 {
64 
65  *mutex = MUTEX_STATUS_UNLOCKED;
66 
67  critical_exit(status);
68 }
69 /*---------------------------------------------------------------------------*/
70 /** @} */
static void critical_exit(int_master_status_t status)
Exit a critical section and restore the master interrupt.
Definition: critical.h:81
static int_master_status_t critical_enter()
Enter a critical section.
Definition: critical.h:65
INT_MASTER_STATUS_DATATYPE int_master_status_t
Master interrupt state representation data type.
Definition: int-master.h:62
void mutex_generic_unlock(volatile mutex_t *mutex)
Unlock a previously acquired mutex.
Definition: mutex.c:61
bool mutex_generic_try_lock(volatile mutex_t *mutex)
Try to lock a mutex.
Definition: mutex.c:45