178 lines
4.3 KiB
C
178 lines
4.3 KiB
C
/*-
|
|
* Copyright (c) 2012 David O'Brien
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/resource.h>
|
|
#include <sys/sysctl.h>
|
|
#include <sys/wait.h>
|
|
|
|
#include <unistd.h>
|
|
#include <stdlib.h>
|
|
#include <signal.h>
|
|
#include <errno.h>
|
|
#include <stdio.h>
|
|
#include <string.h>
|
|
#include <time.h>
|
|
#include <err.h>
|
|
#include <assert.h>
|
|
|
|
#ifndef SLEEP
|
|
#define SLEEP 20 /* seconds */
|
|
#endif
|
|
|
|
static int verbose;
|
|
|
|
static void
|
|
usage(void)
|
|
{
|
|
fprintf(stderr, "usage: %s\n", getprogname());
|
|
fprintf(stderr, "\t\t-n : length of fork(2) chain\n");
|
|
fprintf(stderr, "\t\t-t : limit run-time seconds\n");
|
|
exit(1);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
void term(int);
|
|
void
|
|
term(int signum)
|
|
{
|
|
|
|
if (getpid() == getpgrp() || verbose) {
|
|
fprintf(stderr,
|
|
"pid %d pgroup %d (ppid %d): Received SIGTERM(%d), exiting...\n",
|
|
getpid(), getpgrp(), getppid(), signum);
|
|
}
|
|
exit(1);
|
|
}
|
|
|
|
void angel_of_mercy(int);
|
|
void
|
|
angel_of_mercy(int sig __unused)
|
|
{
|
|
|
|
signal(SIGALRM, SIG_IGN); /* ignore this signal */
|
|
printf("Master process: alarmed waking up\n");
|
|
killpg(0, SIGTERM);
|
|
return;
|
|
}
|
|
|
|
int bombing_run(unsigned, int);
|
|
int
|
|
bombing_run(unsigned chainlen, int stime)
|
|
{
|
|
struct rusage ru;
|
|
pid_t pid, cpid;
|
|
int status;
|
|
|
|
if (chainlen) {
|
|
switch (pid = fork()) {
|
|
case -1:
|
|
errx(1, "%s: can't fork", __func__);
|
|
|
|
case 0:
|
|
/* This is the code the child runs. */
|
|
bombing_run(--chainlen, stime);
|
|
break;
|
|
|
|
default:
|
|
/* This is the code the parent runs. */
|
|
if (getpid() == getpgrp()) {
|
|
signal(SIGALRM, angel_of_mercy);
|
|
alarm(stime); // time for bombing run...
|
|
cpid = wait4(pid, &status, 0, &ru);
|
|
alarm(0);
|
|
printf(
|
|
"Cleanly shutting down - pid %d pgroup %d (ppid %d)\n",
|
|
getpid(), getpgrp(), getppid());
|
|
} else {
|
|
cpid = wait4(pid, &status, 0, &ru);
|
|
}
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
time_t start /*,tvec*/;
|
|
char *endptr, *ctm;
|
|
size_t len;
|
|
int nflag, tflag;
|
|
int ch, k, maxprocperuid;
|
|
|
|
(void)signal(SIGTERM, term);
|
|
|
|
nflag = 0;
|
|
tflag = SLEEP;
|
|
|
|
start = time(NULL);
|
|
ctm = ctime(&start);
|
|
ctm[24] = '\0'; // see: man 3 ctime
|
|
fprintf(stderr, "*** fork() generation started on \"%s\" ***\n", ctm);
|
|
|
|
while ((ch = getopt(argc, argv, "n:t:v")) != -1)
|
|
switch (ch) {
|
|
case 'n':
|
|
nflag = strtol(optarg, &endptr, 10);
|
|
if (nflag <= 0 || *endptr != '\0')
|
|
errx(1, "illegal number, -n argument -- %s",
|
|
optarg);
|
|
break;
|
|
case 't':
|
|
tflag = strtol(optarg, &endptr, 10);
|
|
if (tflag <= 0 || *endptr != '\0')
|
|
errx(1, "illegal number, -t argument -- %s",
|
|
optarg);
|
|
break;
|
|
case 'v':
|
|
++verbose;
|
|
break;
|
|
default:
|
|
usage();
|
|
}
|
|
argv += optind;
|
|
|
|
if (!nflag) {
|
|
len = sizeof(maxprocperuid);
|
|
k = sysctlbyname("kern.maxprocperuid", &maxprocperuid, &len,
|
|
NULL, 0);
|
|
assert(k != ENOMEM);
|
|
/* Try to allow a shell to still be started. */
|
|
nflag = maxprocperuid - 10;
|
|
}
|
|
|
|
// Ensure a unique process group to make killing all children easier.
|
|
setpgrp(0,0);
|
|
printf(" pid %d pgroup %d (ppid %d), %d fork chain over %d sec\n",
|
|
getpid(), getpgrp(), getppid(), nflag - 1, tflag);
|
|
|
|
return bombing_run(nflag, tflag);
|
|
}
|