1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) International Business Machines Corp., 2001
4 */
5
6 /*\
7 * [Description]
8 *
9 * Check that:
10 * - fork() in parent returns the same pid as getpid() in child
11 * - getppid() in child returns the same pid as getpid() in parent
12 */
13
14 #include <errno.h>
15
16 #include "tst_test.h"
17
18 static pid_t *child_pid;
19
verify_getpid(void)20 static void verify_getpid(void)
21 {
22 pid_t proc_id;
23 pid_t pid;
24 pid_t pproc_id;
25
26 proc_id = getpid();
27 pid = SAFE_FORK();
28
29 if (pid == 0) {
30 pproc_id = getppid();
31
32 if (pproc_id != proc_id) {
33 tst_res(TFAIL, "child getppid() (%d) != parent getpid() (%d)",
34 pproc_id, proc_id);
35 } else {
36 tst_res(TPASS, "child getppid() == parent getpid() (%d)", proc_id);
37 }
38
39 *child_pid = getpid();
40
41 return;
42 }
43
44 tst_reap_children();
45
46 if (*child_pid != pid)
47 tst_res(TFAIL, "child getpid() (%d) != parent fork() (%d)", *child_pid, pid);
48 else
49 tst_res(TPASS, "child getpid() == parent fork() (%d)", pid);
50 }
51
setup(void)52 static void setup(void)
53 {
54 child_pid = SAFE_MMAP(NULL, sizeof(pid_t), PROT_READ | PROT_WRITE,
55 MAP_ANONYMOUS | MAP_SHARED, -1, 0);
56 }
57
cleanup(void)58 static void cleanup(void)
59 {
60 SAFE_MUNMAP(child_pid, sizeof(pid_t));
61 }
62
63 static struct tst_test test = {
64 .forks_child = 1,
65 .setup = setup,
66 .cleanup = cleanup,
67 .test_all = verify_getpid,
68 };
69