1*0658a096SFlorian Weimer /*
2*0658a096SFlorian Weimer * Copyright (c) 2021 Alexey Dobriyan <adobriyan@gmail.com>
3*0658a096SFlorian Weimer *
4*0658a096SFlorian Weimer * Permission to use, copy, modify, and distribute this software for any
5*0658a096SFlorian Weimer * purpose with or without fee is hereby granted, provided that the above
6*0658a096SFlorian Weimer * copyright notice and this permission notice appear in all copies.
7*0658a096SFlorian Weimer *
8*0658a096SFlorian Weimer * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9*0658a096SFlorian Weimer * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10*0658a096SFlorian Weimer * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11*0658a096SFlorian Weimer * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12*0658a096SFlorian Weimer * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13*0658a096SFlorian Weimer * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14*0658a096SFlorian Weimer * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15*0658a096SFlorian Weimer */
16*0658a096SFlorian Weimer // Test that /proc/*/task never contains "0".
17*0658a096SFlorian Weimer #include <sys/types.h>
18*0658a096SFlorian Weimer #include <dirent.h>
19*0658a096SFlorian Weimer #include <signal.h>
20*0658a096SFlorian Weimer #include <stdio.h>
21*0658a096SFlorian Weimer #include <stdlib.h>
22*0658a096SFlorian Weimer #include <string.h>
23*0658a096SFlorian Weimer #include <unistd.h>
24*0658a096SFlorian Weimer #include <pthread.h>
25*0658a096SFlorian Weimer
26*0658a096SFlorian Weimer static pid_t pid = -1;
27*0658a096SFlorian Weimer
atexit_hook(void)28*0658a096SFlorian Weimer static void atexit_hook(void)
29*0658a096SFlorian Weimer {
30*0658a096SFlorian Weimer if (pid > 0) {
31*0658a096SFlorian Weimer kill(pid, SIGKILL);
32*0658a096SFlorian Weimer }
33*0658a096SFlorian Weimer }
34*0658a096SFlorian Weimer
f(void * _)35*0658a096SFlorian Weimer static void *f(void *_)
36*0658a096SFlorian Weimer {
37*0658a096SFlorian Weimer return NULL;
38*0658a096SFlorian Weimer }
39*0658a096SFlorian Weimer
sigalrm(int _)40*0658a096SFlorian Weimer static void sigalrm(int _)
41*0658a096SFlorian Weimer {
42*0658a096SFlorian Weimer exit(0);
43*0658a096SFlorian Weimer }
44*0658a096SFlorian Weimer
main(void)45*0658a096SFlorian Weimer int main(void)
46*0658a096SFlorian Weimer {
47*0658a096SFlorian Weimer pid = fork();
48*0658a096SFlorian Weimer if (pid == 0) {
49*0658a096SFlorian Weimer /* child */
50*0658a096SFlorian Weimer while (1) {
51*0658a096SFlorian Weimer pthread_t pth;
52*0658a096SFlorian Weimer pthread_create(&pth, NULL, f, NULL);
53*0658a096SFlorian Weimer pthread_join(pth, NULL);
54*0658a096SFlorian Weimer }
55*0658a096SFlorian Weimer } else if (pid > 0) {
56*0658a096SFlorian Weimer /* parent */
57*0658a096SFlorian Weimer atexit(atexit_hook);
58*0658a096SFlorian Weimer
59*0658a096SFlorian Weimer char buf[64];
60*0658a096SFlorian Weimer snprintf(buf, sizeof(buf), "/proc/%u/task", pid);
61*0658a096SFlorian Weimer
62*0658a096SFlorian Weimer signal(SIGALRM, sigalrm);
63*0658a096SFlorian Weimer alarm(1);
64*0658a096SFlorian Weimer
65*0658a096SFlorian Weimer while (1) {
66*0658a096SFlorian Weimer DIR *d = opendir(buf);
67*0658a096SFlorian Weimer struct dirent *de;
68*0658a096SFlorian Weimer while ((de = readdir(d))) {
69*0658a096SFlorian Weimer if (strcmp(de->d_name, "0") == 0) {
70*0658a096SFlorian Weimer exit(1);
71*0658a096SFlorian Weimer }
72*0658a096SFlorian Weimer }
73*0658a096SFlorian Weimer closedir(d);
74*0658a096SFlorian Weimer }
75*0658a096SFlorian Weimer
76*0658a096SFlorian Weimer return 0;
77*0658a096SFlorian Weimer } else {
78*0658a096SFlorian Weimer perror("fork");
79*0658a096SFlorian Weimer return 1;
80*0658a096SFlorian Weimer }
81*0658a096SFlorian Weimer }
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