regress/lib/libpthread/sigmask4/sigmask4.c

   1 /*
   2  * Create a thread that is running [the sleeper] with a signal blocked
   3  * and use the other thread to block on select. This is so that we can
   4  * send the signal on the "select" thread. Interrupt the selected thread
   5  * with alarm. Detects bug in libpthread where we did not use the proper
   6  * signal mask, so only the first signal got delivered.
   7  */
   8 #include <signal.h>
   9 #include <stdlib.h>
  10 #include <unistd.h>
  11 #include <err.h>
  12 #include <errno.h>
  13 #include <pthread.h>
  14
  15 static sig_atomic_t count = 0;
  16
  17 static void
  18 handler(int sig)
  19 {
  20         count++;
  21 }
  22
  23 static void *
  24 sleeper(void* arg)
  25 {
  26     int i;
  27     for (i = 0; i < 10; i++)
  28             sleep(1);
  29     exit(1);
  30 }
  31
  32 int
  33 main(int argc, char** argv)
  34 {
  35         pthread_t id;
  36         struct sigaction act;
  37
  38         act.sa_sigaction = NULL;
  39         sigemptyset(&act.sa_mask);
  40         act.sa_flags = 0;
  41         act.sa_handler = handler;
  42
  43         if (sigaction(SIGALRM, &act, NULL) == -1)
  44                 err(1, "sigaction");
  45
  46         sigaddset(&act.sa_mask, SIGALRM);
  47         pthread_sigmask(SIG_SETMASK, &act.sa_mask, NULL);
  48
  49         pthread_create(&id, NULL, sleeper, NULL);
  50         sleep(1);
  51
  52         sigemptyset(&act.sa_mask);
  53         pthread_sigmask(SIG_SETMASK, &act.sa_mask, NULL);
  54
  55         for (;;) {
  56                 alarm(1);
  57                 if (select(1, NULL, NULL, NULL, NULL) == -1 && errno == EINTR)
  58                         if (count == 2)
  59                                 return 0;
  60         }
  61 }