1  #include <semaphore.h>
       2  #include <stdio.h>
       3  #include <unistd.h>
       4  #include <pthread.h>
       5  #include <internaltypes.h>
       6  
       7  #ifndef SEM_WAIT
       8  # define SEM_WAIT(s) sem_wait (s)
       9  #endif
      10  
      11  static void *
      12  tf (void *arg)
      13  {
      14  #ifdef PREPARE
      15    PREPARE
      16  #endif
      17    SEM_WAIT (arg);
      18    return NULL;
      19  }
      20  
      21  int
      22  main (void)
      23  {
      24    int tries = 5;
      25    pthread_t th;
      26    union
      27    {
      28      sem_t s;
      29      struct new_sem ns;
      30    } u;
      31   again:
      32    if (sem_init (&u.s, 0, 0) != 0)
      33      {
      34        puts ("sem_init failed");
      35        return 1;
      36      }
      37  #if __HAVE_64B_ATOMICS
      38    if ((u.ns.data >> SEM_NWAITERS_SHIFT) != 0)
      39  #else
      40    if (u.ns.nwaiters != 0)
      41  #endif
      42      {
      43        puts ("nwaiters not initialized");
      44        return 1;
      45      }
      46  
      47    if (pthread_create (&th, NULL, tf, &u.s) != 0)
      48      {
      49        puts ("pthread_create failed");
      50        return 1;
      51      }
      52  
      53    sleep (1);
      54  
      55    if (pthread_cancel (th) != 0)
      56      {
      57        puts ("pthread_cancel failed");
      58        return 1;
      59      }
      60  
      61    void *r;
      62    if (pthread_join (th, &r) != 0)
      63      {
      64        puts ("pthread_join failed");
      65        return 1;
      66      }
      67    if (r != PTHREAD_CANCELED && --tries > 0)
      68      {
      69        /* Maybe we get the scheduling right the next time.  */
      70        sem_destroy (&u.s);
      71        goto again;
      72      }
      73  
      74  #if __HAVE_64B_ATOMICS
      75    if ((u.ns.data >> SEM_NWAITERS_SHIFT) != 0)
      76  #else
      77    if (u.ns.nwaiters != 0)
      78  #endif
      79      {
      80        puts ("nwaiters not reset");
      81        return 1;
      82      }
      83  
      84    return 0;
      85  }