src/functional/sem_init.c

   1 /* unnamed semaphore sanity check */
   2 #include <pthread.h>
   3 #include <semaphore.h>
   4 #include <time.h>
   5 #include <string.h>
   6 #include <errno.h>
   7 #include "test.h"
   8
   9 #define T(f) if(f) t_error(#f" failed: %s\n", strerror(errno))
  10 #define T2(r,f) if((r=(f))) t_error(#f" failed: %s\n", strerror(r))
  11
  12 static void *start(void *arg)
  13 {
  14         struct timespec ts;
  15         sem_t *s = arg;
  16         T(clock_gettime(CLOCK_REALTIME, &ts));
  17         ts.tv_sec += 1;
  18         T(sem_post(s));
  19         T(sem_timedwait(s+1, &ts));
  20         return 0;
  21 }
  22
  23 static void many_waiters()
  24 {
  25         pthread_t t[3];
  26         sem_t s[2];
  27         int r;
  28         void *p;
  29
  30         T(sem_init(s, 0, 0));
  31         T(sem_init(s+1, 0, 0));
  32         T2(r,pthread_create(t, 0, start, s));
  33         T2(r,pthread_create(t+1, 0, start, s));
  34         T2(r,pthread_create(t+2, 0, start, s));
  35         T(sem_wait(s));
  36         T(sem_wait(s));
  37         T(sem_wait(s));
  38         T(sem_getvalue(s, &r));
  39         if (r)
  40                 t_error("sem value should be 0, got %d\n", r);
  41         T(sem_post(s+1));
  42         T(sem_post(s+1));
  43         T(sem_post(s+1));
  44         T2(r,pthread_join(t[0],&p));
  45         T2(r,pthread_join(t[1],&p));
  46         T2(r,pthread_join(t[2],&p));
  47         T(sem_getvalue(s+1, &r));
  48         if (r)
  49                 t_error("sem value should be 0, got %d\n", r);
  50         T(sem_destroy(s));
  51         T(sem_destroy(s+1));
  52 }
  53
  54 static void single_thread()
  55 {
  56         struct timespec ts;
  57         sem_t s;
  58         int r;
  59
  60         T(sem_init(&s, 0, 1));
  61         T(sem_wait(&s));
  62         T(sem_getvalue(&s, &r));
  63         if (r)
  64                 t_error("sem value should be 0, got %d\n", r);
  65         if (sem_trywait(&s) != -1 || errno != EAGAIN)
  66                 t_error("sem_trywait should fail with EAGAIN, got %s\n", strerror(errno));
  67         errno = 0;
  68         T(clock_gettime(CLOCK_REALTIME, &ts));
  69         if (sem_timedwait(&s, &ts)!=-1 || errno != ETIMEDOUT)
  70                 t_error("sem_timedwait should fail with ETIMEDOUT, got %s\n", strerror(errno));
  71         T(sem_destroy(&s));
  72 }
  73
  74 int main(void)
  75 {
  76         single_thread();
  77         many_waiters();
  78         return t_status;
  79 }