/* $NetBSD: cmd_pollpal.c,v 1.1 2020/04/30 00:48:10 christos Exp $ */
/*-
* Copyright (c) 2020 The NetBSD Foundation, Inc.
* 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <sys/cdefs.h>
__RCSID("$NetBSD: cmd_pollpal.c,v 1.1 2020/04/30 00:48:10 christos Exp $");
#include <sys/mman.h>
#include <errno.h>
#include <err.h>
#include <fcntl.h>
#include <poll.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <unistd.h>
#define BUFFLEN 100
#define TIMEOUT 10000
static int fd;
static __dead __printflike(2, 3) void
done(int e, const char *msg, ...)
{
if (msg) {
va_list ap;
va_start(ap, msg);
verr(e, msg, ap);
/*NOTREACHED*/
va_end(ap);
}
exit(e);
}
static __dead void
handler(int sig)
{
done(EXIT_SUCCESS, NULL);
}
static const char dev[] = "/dev/pollpal";
static const char wbuf[] = "abcdefghijklmnopqrstuvwxyz";
int
main(int argc, char **argv)
{
struct pollfd fds;
ssize_t ret;
size_t i;
char rbuf[BUFFLEN];
setprogname(argv[0]);
fd = open(dev, O_RDWR, 0);
if (fd == -1)
err(EXIT_FAILURE, "open `%s'", dev);
fds.fd = fd;
fds.events = POLLOUT|POLLIN;
signal(SIGINT, handler);
for (i = 1; i <= 100; i++) {
ret = poll(&fds, 1, TIMEOUT);
if (ret == -1) {
if (errno == EINTR)
continue;
done(EXIT_FAILURE, "poll");
}
printf("Poll_executing %zu times\n", i);
if (ret == 0) {
printf("%d seconds elapsed \n.TIMEOUT.\n",
TIMEOUT / 1000);
done(EXIT_SUCCESS, NULL);
}
if (fds.revents & (POLLERR | POLLHUP | POLLNVAL))
done(EXIT_FAILURE, "ERR|HUP|NVAL");
if (fds.revents & POLLOUT) {
do {
ret = write(fd, wbuf, sizeof(wbuf) - 1);
} while (ret == -1 && errno == EINTR);
if (ret == -1) {
done(EXIT_FAILURE, "write");
}
printf("Wrote %zd byte\n", ret);
}
if (fds.revents & POLLIN) {
memset(rbuf, 0, BUFFLEN);
do {
ret = read(fd, rbuf, BUFFLEN);
} while (ret == -1 && errno == EINTR);
if (ret == -1) {
done(EXIT_FAILURE, "read");
}
printf("Read %zd bytes\n", ret);
}
}
done(EXIT_SUCCESS, NULL);
}
