compiler-rt/test/tsan/signal_block.cpp

   1 // RUN: %clang_tsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
   2
   3 // Test that a signal is not delivered when it is blocked.
   4
   5 #include "test.h"
   6 #include <semaphore.h>
   7 #include <signal.h>
   8 #include <errno.h>
   9
  10 int stop;
  11 sig_atomic_t signal_blocked;
  12
  13 void handler(int signum) {
  14   if (signal_blocked) {
  15     fprintf(stderr, "signal arrived when blocked\n");
  16     exit(1);
  17   }
  18 }
  19
  20 void *thread(void *arg) {
  21   sigset_t myset;
  22   sigemptyset(&myset);
  23   sigaddset(&myset, SIGUSR1);
  24   while (!__atomic_load_n(&stop, __ATOMIC_RELAXED)) {
  25     usleep(1);
  26     if (pthread_sigmask(SIG_BLOCK, &myset, 0)) {
  27       fprintf(stderr, "pthread_sigmask failed %d\n", errno);
  28       exit(1);
  29     }
  30     signal_blocked = 1;
  31     usleep(1);
  32     signal_blocked = 0;
  33     if (pthread_sigmask(SIG_UNBLOCK, &myset, 0)) {
  34       fprintf(stderr, "pthread_sigmask failed %d\n", errno);
  35       exit(1);
  36     }
  37   }
  38   return 0;
  39 }
  40
  41 int main(int argc, char** argv) {
  42   struct sigaction act = {};
  43   act.sa_handler = &handler;
  44   if (sigaction(SIGUSR1, &act, 0)) {
  45     fprintf(stderr, "sigaction failed %d\n", errno);
  46     return 1;
  47   }
  48   pthread_t th;
  49   pthread_create(&th, 0, thread, 0);
  50   for (int i = 0; i < 100000; i++)
  51     pthread_kill(th, SIGUSR1);
  52   __atomic_store_n(&stop, 1, __ATOMIC_RELAXED);
  53   pthread_join(th, 0);
  54   fprintf(stderr, "DONE\n");
  55   return 0;
  56 }
  57
  58 // CHECK-NOT: ThreadSanitizer CHECK
  59 // CHECK-NOT: WARNING: ThreadSanitizer:
  60 // CHECK: DONE