gdb/testsuite/gdb.threads/sigthread.c

   1 /* Test case for C-c sent to threads with pending signals.  Before I
   2    even get there, creating a thread and sending it a signal before it
   3    has a chance to run leads to an internal error in GDB.  We need to
   4    record that there's a pending SIGSTOP, so that we'll ignore it
   5    later, and pass the current signal back to the thread.
   6
   7    The fork/vfork case has similar trouble but that's even harder
   8    to get around.  We may need to send a SIGCONT to cancel out the
   9    SIGSTOP.  Different kernels may do different things if the thread
  10    is stopped by ptrace and sent a SIGSTOP.  */
  11
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <stdlib.h>
  15 #include <pthread.h>
  16 #include <signal.h>
  17
  18 /* Loop long enough for GDB to send a few signals of its own, but
  19    don't hang around eating CPU forever if something goes wrong during
  20    testing.  */
  21 #define NSIGS 10000000
  22
  23 pthread_barrier_t barrier;
  24
  25 void
  26 handler (int sig)
  27 {
  28   ;
  29 }
  30
  31 pthread_t main_thread;
  32 pthread_t child_thread, child_thread_two;
  33
  34 void *
  35 child_two (void *arg)
  36 {
  37   int i;
  38
  39   pthread_barrier_wait (&barrier);
  40
  41   for (i = 0; i < NSIGS; i++)
  42     pthread_kill (child_thread, SIGUSR1);
  43 }
  44
  45 void *
  46 thread_function (void *arg)
  47 {
  48   int i;
  49
  50   pthread_barrier_wait (&barrier);
  51
  52   for (i = 0; i < NSIGS; i++)
  53     pthread_kill (child_thread_two, SIGUSR2);
  54 }
  55
  56 int main()
  57 {
  58   int i;
  59
  60   signal (SIGUSR1, handler);
  61   signal (SIGUSR2, handler);
  62
  63   pthread_barrier_init (&barrier, NULL, 3);
  64
  65   main_thread = pthread_self ();
  66   pthread_create (&child_thread, NULL, thread_function, NULL);
  67   pthread_create (&child_thread_two, NULL, child_two, NULL);
  68
  69   pthread_barrier_wait (&barrier);
  70
  71   for (i = 0; i < NSIGS; i++)
  72     pthread_kill (child_thread_two, SIGUSR1);
  73
  74   pthread_join (child_thread, NULL);
  75
  76   exit (0);
  77 }