summaryrefslogtreecommitdiff
path: root/qa/src/pthread_barrier.h
blob: a01028e57910510a09a563d595c2a218694993a1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
/*
 * pthread_barrier code if libpthread does not have it ...
 *
 * Original code from Brent Priddy's code fragment at
 * http://stackoverflow.com/questions/3640853
 *
 * Copyright (c) 2010 Brent Priddy.
 *
 * 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.
 *
 */

typedef int pthread_barrierattr_t;
typedef struct
{
    pthread_mutex_t mutex;
    pthread_cond_t cond;
    int count;
    int tripCount;
} pthread_barrier_t;


int pthread_barrier_init(pthread_barrier_t *barrier, const pthread_barrierattr_t *attr, unsigned int count)
{
    if(count == 0)
    {
        errno = EINVAL;
        return -1;
    }
    if(pthread_mutex_init(&barrier->mutex, 0) < 0)
    {
        return -1;
    }
    if(pthread_cond_init(&barrier->cond, 0) < 0)
    {
        pthread_mutex_destroy(&barrier->mutex);
        return -1;
    }
    barrier->tripCount = count;
    barrier->count = 0;

    return 0;
}

int pthread_barrier_destroy(pthread_barrier_t *barrier)
{
    pthread_cond_destroy(&barrier->cond);
    pthread_mutex_destroy(&barrier->mutex);
    return 0;
}

int pthread_barrier_wait(pthread_barrier_t *barrier)
{
    pthread_mutex_lock(&barrier->mutex);
    ++(barrier->count);
    if(barrier->count >= barrier->tripCount)
    {
        barrier->count = 0;
        pthread_cond_broadcast(&barrier->cond);
        pthread_mutex_unlock(&barrier->mutex);
        return 1;
    }
    else
    {
        pthread_cond_wait(&barrier->cond, &(barrier->mutex));
        pthread_mutex_unlock(&barrier->mutex);
        return 0;
    }
}