compiler-rt/test/lsan/TestCases/Linux/signal_during_stop_the_world.cpp

   1 // Test StopTheWorld behavior during signal storm.
   2 // Historically StopTheWorld crashed because did not handle EINTR properly.
   3 // The test is somewhat convoluted, but that's what caused crashes previously.
   4
   5 // RUN: %clangxx_lsan -O1 %s -o %t && %run %t 2>&1 | FileCheck %s
   6
   7 #include <stdio.h>
   8 #include <stdlib.h>
   9 #include <signal.h>
  10 #include <unistd.h>
  11 #include <sys/types.h>
  12 #include <sys/prctl.h>
  13 #include <sys/wait.h>
  14 #include <time.h>
  15 #include <pthread.h>
  16 #include <sanitizer/lsan_interface.h>
  17
  18 static void handler(int signo);
  19 static void *thr(void *arg);
  20
  21 int main() {
  22   struct sigaction act = {};
  23   act.sa_handler = handler;
  24   sigaction(SIGPROF, &act, 0);
  25
  26   pid_t pid = fork();
  27   if (pid < 0) {
  28     fprintf(stderr, "failed to fork\n");
  29     exit(1);
  30   }
  31   if (pid == 0) {
  32     // Child constantly sends signals to parent to cause spurious return from
  33     // waitpid in StopTheWorld.
  34     prctl(PR_SET_PDEATHSIG, SIGTERM, 0, 0, 0);
  35     pid_t parent = getppid();
  36     for (;;) {
  37       // There is no strong reason for these two particular signals,
  38       // but at least one of them ought to unblock waitpid.
  39       kill(parent, SIGCHLD);
  40       kill(parent, SIGPROF);
  41     }
  42   }
  43   usleep(10000);  // Let the child start.
  44   __lsan_do_leak_check();
  45   // Kill and join the child.
  46   kill(pid, SIGTERM);
  47   waitpid(pid, 0, 0);
  48   sleep(1);  // If the tracer thread still runs, give it time to crash.
  49   fprintf(stderr, "DONE\n");
  50 // CHECK: DONE
  51 }
  52
  53 static void handler(int signo) {
  54 }
  55
  56 static void *thr(void *arg) {
  57   for (;;)
  58     sleep(1);
  59   return 0;
  60 }