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/* $OpenBSD: nanosleep.c,v 1.2 2002/02/17 05:33:33 art Exp $ */
/*
* Written by Artur Grabowski <art@openbsd.org> 2002 Public Domain.
*/
#include <sys/types.h>
#include <sys/time.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <time.h>
#include <err.h>
#include <signal.h>
int trivial(void);
int with_signal(void);
int time_elapsed(void);
int time_elapsed_with_signal(void);
int short_time(void);
void sighandler(int);
int
main(int argc, char **argv)
{
int ch, ret;
ret = 0;
while ((ch = getopt(argc, argv, "tseES")) != -1) {
switch (ch) {
case 't':
ret |= trivial();
break;
case 's':
ret |= with_signal();
break;
case 'e':
ret |= time_elapsed();
break;
case 'E':
ret |= time_elapsed_with_signal();
break;
case 'S':
ret |= short_time();
default:
fprintf(stderr, "Usage: nanosleep [-tse]\n");
exit(1);
}
}
return (ret);
}
void
sighandler(int signum)
{
}
int
trivial(void)
{
struct timespec ts, rts;
ts.tv_sec = 0;
ts.tv_nsec = 30000000;
rts.tv_sec = 4711; /* Just add to the confusion */
rts.tv_nsec = 4711;
if (nanosleep(&ts, &rts) < 0) {
warn("trivial: nanosleep");
return 1;
}
/*
* Just check that we don't get any leftover time if we sleep the
* amount of time we want to sleep.
* If we receive any signal, something is wrong anyway.
*/
if (rts.tv_sec != 0 || rts.tv_nsec != 0) {
warnx("trivial: non-zero time? %d/%d", rts.tv_sec,
rts.tv_nsec);
return 1;
}
return 0;
}
int
with_signal(void)
{
struct timespec ts, rts;
pid_t pid;
int status;
signal(SIGUSR1, sighandler);
pid = getpid();
switch(fork()) {
case -1:
err(1, "fork");
default:
ts.tv_sec = 1;
ts.tv_nsec = 0;
nanosleep(&ts, NULL);
kill(pid, SIGUSR1);
exit(0);
}
ts.tv_sec = 10;
ts.tv_nsec = 0;
rts.tv_sec = 0;
rts.tv_nsec = 0;
if (nanosleep(&ts, &rts) == 0) {
warn("with-signal: nanosleep");
return 1;
}
if (rts.tv_sec == 0 && rts.tv_nsec == 0) {
warnx("with-signal: zero time");
return 1;
}
if (wait(&status) < 0)
err(1, "wait");
return 0;
}
int
time_elapsed(void)
{
struct timespec ts;
struct timeval stv, etv;
ts.tv_sec = 0;
ts.tv_nsec = 500000000;
if (gettimeofday(&stv, NULL) < 0) {
warn("gettimeofday");
return 1;
}
if (nanosleep(&ts, NULL) < 0) {
warn("nanosleep");
return 1;
}
if (gettimeofday(&etv, NULL) < 0) {
warn("gettimeofday");
return 1;
}
timersub(&etv, &stv, &stv);
if (stv.tv_sec == 0 && stv.tv_usec < 500000) {
warnx("slept less than 0.5 sec");
return 1;
}
return 0;
}
int
time_elapsed_with_signal(void)
{
struct timespec ts, rts;
struct timeval stv, etv;
pid_t pid;
int status;
signal(SIGUSR1, sighandler);
pid = getpid();
switch(fork()) {
case -1:
err(1, "fork");
default:
ts.tv_sec = 1;
ts.tv_nsec = 0;
nanosleep(&ts, NULL);
kill(pid, SIGUSR1);
exit(0);
}
ts.tv_sec = 10;
ts.tv_nsec = 0;
rts.tv_sec = 0;
rts.tv_nsec = 0;
if (gettimeofday(&stv, NULL) < 0) {
warn("gettimeofday");
return 1;
}
if (nanosleep(&ts, &rts) == 0) {
warn("nanosleep");
return 1;
}
if (gettimeofday(&etv, NULL) < 0) {
warn("gettimeofday");
return 1;
}
timersub(&etv, &stv, &stv);
etv.tv_sec = rts.tv_sec;
etv.tv_usec = rts.tv_nsec / 1000 + 1; /* the '+ 1' is a "roundup" */
timeradd(&etv, &stv, &stv);
if (stv.tv_sec == 0 && stv.tv_usec < 500000) {
warnx("slept less than 0.5 sec");
return 1;
}
if (wait(&status) < 0)
err(1, "wait");
return 0;
}
int
short_time(void)
{
struct timespec ts, rts;
pid_t pid;
int status;
signal(SIGUSR1, sighandler);
pid = getpid();
switch(fork()) {
case -1:
err(1, "fork");
default:
/* Sleep two seconds, then shoot parent. */
ts.tv_sec = 2;
ts.tv_nsec = 0;
nanosleep(&ts, NULL);
kill(pid, SIGUSR1);
exit(0);
}
ts.tv_sec = 0;
ts.tv_nsec = 1;
if (nanosleep(&ts, NULL) <= 0) {
warn("short_time: nanosleep");
return 1;
}
if (wait(&status) < 0)
err(1, "wait");
return 0;
}
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