xref: /aosp_15_r20/external/ltp/testcases/kernel/syscalls/alarm/alarm07.c (revision 49cdfc7efb34551c7342be41a7384b9c40d7cab7)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (c) International Business Machines  Corp., 2001
4  * Author: Wayne Boyer
5  * Copyright (c) Linux Test Project, 2002-2022
6  */
7 
8 /*\
9  * [Description]
10  *
11  * Verify that SIGALRM signal scheduled by alarm() in the parent process
12  * is not delivered to the child process.
13  */
14 
15 #include <stdlib.h>
16 #include "tst_test.h"
17 
18 static volatile int alarm_cnt;
19 
verify_alarm(void)20 static void verify_alarm(void)
21 {
22 	pid_t pid;
23 
24 	alarm_cnt = 0;
25 
26 	TST_EXP_PASS_SILENT(alarm(1));
27 	pid = SAFE_FORK();
28 
29 	sleep(3);
30 
31 	if (pid == 0) {
32 		TST_EXP_EQ_LU(alarm_cnt, 0);
33 		exit(0);
34 	}
35 
36 	TST_EXP_EQ_LU(alarm_cnt, 1);
37 }
38 
sighandler(int sig LTP_ATTRIBUTE_UNUSED)39 static void sighandler(int sig LTP_ATTRIBUTE_UNUSED)
40 {
41 	alarm_cnt++;
42 }
43 
setup(void)44 static void setup(void)
45 {
46 	SAFE_SIGNAL(SIGALRM, sighandler);
47 }
48 
49 static struct tst_test test = {
50 	.test_all = verify_alarm,
51 	.setup = setup,
52 	.forks_child = 1,
53 };
54