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
main()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
handler(int signo)53 static void handler(int signo) {
54 }
55
thr(void * arg)56 static void *thr(void *arg) {
57 for (;;)
58 sleep(1);
59 return 0;
60 }
61