1 // commit: 7e6be42a77989c01155bdc7333ea58206e1563d4 2011-03-08
2 // pthread_once should not deadlock
3 #include <pthread.h>
4 #include <semaphore.h>
5 #include <errno.h>
6 #include <string.h>
7 #include "test.h"
8
9 #define T(f) if ((r=(f))) t_error(#f " failed: %s\n", strerror(r))
10 #define E(f) if (f) t_error(#f " failed: %s\n", strerror(errno))
11
12 static int count;
13
init(void)14 static void init(void)
15 {
16 count++;
17 }
18
start(void * arg)19 static void *start(void *arg)
20 {
21 void **a = arg;
22 int r;
23 E(sem_post(a[1]));
24 T(pthread_once(a[0], init));
25 E(sem_post(a[1]));
26 return 0;
27 }
28
deadlocked(sem_t * s)29 static int deadlocked(sem_t *s)
30 {
31 struct timespec ts;
32
33 E(sem_wait(s));
34 E(clock_gettime(CLOCK_REALTIME, &ts));
35 ts.tv_nsec += 100*1000*1000;
36 if (ts.tv_nsec >= 1000*1000*1000) {
37 ts.tv_nsec -= 1000*1000*1000;
38 ts.tv_sec += 1;
39 }
40 errno = 0;
41 E(sem_timedwait(s,&ts));
42 if (errno != ETIMEDOUT)
43 return 0;
44 t_error("pthread_once deadlocked\n");
45 return 1;
46 }
47
main(void)48 int main(void)
49 {
50 pthread_t t1,t2,t3;
51 pthread_once_t once = PTHREAD_ONCE_INIT;
52 sem_t s1,s2,s3;
53 void *p;
54 int r;
55
56 E(sem_init(&s1,0,0));
57 E(sem_init(&s2,0,0));
58 E(sem_init(&s3,0,0));
59 T(pthread_create(&t1, 0, start, (void*[]){&once,&s1}));
60 T(pthread_create(&t2, 0, start, (void*[]){&once,&s2}));
61 T(pthread_create(&t3, 0, start, (void*[]){&once,&s3}));
62 if (!deadlocked(&s1)) T(pthread_join(t1,&p));
63 if (!deadlocked(&s2)) T(pthread_join(t2,&p));
64 if (!deadlocked(&s3)) T(pthread_join(t3,&p));
65 if (count != 1)
66 t_error("pthread_once ran init %d times instead of once\n", count);
67 E(sem_destroy(&s1));
68 E(sem_destroy(&s2));
69 E(sem_destroy(&s3));
70 return t_status;
71 }
72