1 /*
2  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
3  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4  *
5  * SPDX-License-Identifier: MIT
6  *
7  * Permission is hereby granted, free of charge, to any person obtaining a copy of
8  * this software and associated documentation files (the "Software"), to deal in
9  * the Software without restriction, including without limitation the rights to
10  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
11  * the Software, and to permit persons to whom the Software is furnished to do so,
12  * subject to the following conditions:
13  *
14  * The above copyright notice and this permission notice shall be included in all
15  * copies or substantial portions of the Software.
16  *
17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
19  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
20  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
21  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
23  *
24  * https://www.FreeRTOS.org
25  * https://github.com/FreeRTOS
26  *
27  */
28 
29 #include <pthread.h>
30 #include <stdlib.h>
31 #include <errno.h>
32 
33 #include "wait_for_event.h"
34 
35 struct event
36 {
37     pthread_mutex_t mutex;
38     pthread_mutexattr_t mutexattr;
39     pthread_cond_t cond;
40     bool event_triggered;
41 };
42 /*-----------------------------------------------------------*/
43 
event_create(void)44 struct event * event_create( void )
45 {
46     struct event * ev = malloc( sizeof( struct event ) );
47 
48     if( ev != NULL )
49     {
50         ev->event_triggered = false;
51         pthread_mutexattr_init( &ev->mutexattr );
52         #ifndef __APPLE__
53             pthread_mutexattr_setrobust( &ev->mutexattr, PTHREAD_MUTEX_ROBUST );
54         #endif
55         pthread_mutex_init( &ev->mutex, &ev->mutexattr );
56         pthread_cond_init( &ev->cond, NULL );
57     }
58 
59     return ev;
60 }
61 /*-----------------------------------------------------------*/
62 
event_delete(struct event * ev)63 void event_delete( struct event * ev )
64 {
65     pthread_mutex_destroy( &ev->mutex );
66     pthread_mutexattr_destroy( &ev->mutexattr );
67     pthread_cond_destroy( &ev->cond );
68     free( ev );
69 }
70 /*-----------------------------------------------------------*/
71 
event_wait(struct event * ev)72 bool event_wait( struct event * ev )
73 {
74     if( pthread_mutex_lock( &ev->mutex ) == EOWNERDEAD )
75     {
76         #ifndef __APPLE__
77             /* If the thread owning the mutex died, make the mutex consistent. */
78             pthread_mutex_consistent( &ev->mutex );
79         #endif
80     }
81 
82     while( ev->event_triggered == false )
83     {
84         pthread_cond_wait( &ev->cond, &ev->mutex );
85     }
86 
87     ev->event_triggered = false;
88     pthread_mutex_unlock( &ev->mutex );
89     return true;
90 }
91 /*-----------------------------------------------------------*/
92 
event_wait_timed(struct event * ev,time_t ms)93 bool event_wait_timed( struct event * ev,
94                        time_t ms )
95 {
96     struct timespec ts;
97     int ret = 0;
98 
99     clock_gettime( CLOCK_REALTIME, &ts );
100     ts.tv_sec += ms / 1000;
101     ts.tv_nsec += ( ( ms % 1000 ) * 1000000 );
102     if( pthread_mutex_lock( &ev->mutex ) == EOWNERDEAD )
103     {
104         #ifndef __APPLE__
105             /* If the thread owning the mutex died, make the mutex consistent. */
106             pthread_mutex_consistent( &ev->mutex );
107         #endif
108     }
109 
110     while( ( ev->event_triggered == false ) && ( ret == 0 ) )
111     {
112         ret = pthread_cond_timedwait( &ev->cond, &ev->mutex, &ts );
113 
114         if( ( ret == -1 ) && ( errno == ETIMEDOUT ) )
115         {
116             return false;
117         }
118     }
119 
120     ev->event_triggered = false;
121     pthread_mutex_unlock( &ev->mutex );
122     return true;
123 }
124 /*-----------------------------------------------------------*/
125 
event_signal(struct event * ev)126 void event_signal( struct event * ev )
127 {
128     if( pthread_mutex_lock( &ev->mutex ) == EOWNERDEAD )
129     {
130         #ifndef __APPLE__
131             /* If the thread owning the mutex died, make the mutex consistent. */
132             pthread_mutex_consistent( &ev->mutex );
133         #endif
134     }
135     ev->event_triggered = true;
136     pthread_cond_signal( &ev->cond );
137     pthread_mutex_unlock( &ev->mutex );
138 }
139 /*-----------------------------------------------------------*/
140