cgroup_fj_proc.c revision 6c4d1c6d4b3c116ff88f9209b4860940fb8659a8 
1/******************************************************************************/
2/*                                                                            */
3/* Copyright (c) 2009 FUJITSU LIMITED                                         */
4/*                                                                            */
5/* This program is free software;  you can redistribute it and/or modify      */
6/* it under the terms of the GNU General Public License as published by       */
7/* the Free Software Foundation; either version 2 of the License, or          */
8/* (at your option) any later version.                                        */
9/*                                                                            */
10/* This program is distributed in the hope that it will be useful,            */
11/* but WITHOUT ANY WARRANTY;  without even the implied warranty of            */
12/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See                  */
13/* the GNU General Public License for more details.                           */
14/*                                                                            */
15/* You should have received a copy of the GNU General Public License          */
16/* along with this program;  if not, write to the Free Software               */
17/* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA    */
18/*                                                                            */
19/* Author: Shi Weihua <shiwh@cn.fujitsu.com>                                  */
20/*                                                                            */
21/******************************************************************************/
22
23#include <sys/types.h>
24#include <sys/wait.h>
25#include <err.h>
26#include <errno.h>
27#include <signal.h>
28#include <stdlib.h>
29#include <unistd.h>
30#include <stdio.h>
31
32#define UNUSED __attribute__ ((unused))
33
34static int test_switch = 0;
35
36void sighandler(UNUSED int signo)
37{
38	test_switch = !test_switch;
39}
40
41int main(void)
42{
43	sigset_t sigset;
44	struct sigaction sa;
45	pid_t pid;
46	int status;
47	int count = 0;
48
49	sa.sa_handler = sighandler;
50	if (sigemptyset(&sa.sa_mask) < 0)
51		err(1, "sigemptyset()");
52
53	sa.sa_flags = 0;
54	if (sigaction(SIGUSR1, &sa, NULL) < 0)
55		err(1, "sigaction()");
56
57	if (sigemptyset(&sigset) < 0)
58		err(1, "sigemptyset()");
59
60	/* wait for the signal SIGUSR1 to start testing */
61	sigsuspend(&sigset);
62	if (errno != EINTR)
63		err(1, "sigsuspend()");
64
65	do {
66		count++;
67		pid = fork();
68		if (pid == -1)
69			err(1, "fork()");
70		else if (pid == 0) {
71			return 0;
72		} else {
73			wait(&status);
74		}
75	} while (test_switch);
76
77	return 0;
78}
79