Function timer_helper_thread

src/plugin/timer/timer_create.cpp:171–240

Helper function to support starting threads for SIGEV_THREAD. */

/* Helper function to support starting threads for SIGEV_THREAD.  */
static void *
timer_helper_thread(void *arg)
{
  helper_tid = syscall(SYS_gettid);
  sem_post(&helper_notification);

  /* Wait for the SIGTIMER signal, allowing the setXid signal, and
     none else.  */
  sigset_t ss;
  sigemptyset(&ss);
  sigaddset(&ss, SIGTIMER);

  /* Endless loop of waiting for signals.  The loop is only ended when
     the thread is canceled.  */
  while (1) {
    siginfo_t si;

    /* sigwaitinfo cannot be used here, since it deletes
       SIGCANCEL == SIGTIMER from the set.  */

    pthread_testcancel();

    // int oldtype = LIBC_CANCEL_ASYNC ();

    /* XXX The size argument hopefully will have to be changed to the
       real size of the user-level sigset_t.  */
    int result = sigtimedwait(&ss, &si, NULL);

    // LIBC_CANCEL_RESET (oldtype);

    if (result > 0) {
      if (si.si_code == SI_TIMER) {
        struct timer *tk = (struct timer *)si.si_ptr;

        /* Check the timer is still used and will not go away
           while we are reading the values here.  */
        DmtcpMutexLock(&active_timer_sigev_thread_lock);

        struct timer *runp = active_timer_sigev_thread;
        while (runp != NULL) {
          if (runp == tk) {
            break;
          } else {
            runp = runp->next;
          }
        }

        if (runp != NULL) {
          struct thread_start_data *td =
            (struct thread_start_data *)JALLOC_MALLOC(sizeof(*td));

          /* There is not much we can do if the allocation fails.  */
          if (td != NULL) {
            /* This is the signal we are waiting for.  */
            td->thrfunc = tk->thrfunc;
            td->sival = tk->sival;

            pthread_t th;