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/* $NetBSD: t_fifo.c,v 1.4 2017/01/13 21:30:41 christos Exp $ */

/*-
 * Copyright (c) 2002, 2008 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Luke Mewburn and Jaromir Dolecek.
 *
 * 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>
__COPYRIGHT("@(#) Copyright (c) 2008\
 The NetBSD Foundation, inc. All rights reserved.");
__RCSID("$NetBSD: t_fifo.c,v 1.4 2017/01/13 21:30:41 christos Exp $");

#include <sys/event.h>
#include <sys/stat.h>
#include <sys/wait.h>

#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <atf-c.h>

#include "h_macros.h"

#define FIFONAME "fifo"

ATF_TC(fifo);
ATF_TC_HEAD(fifo, tc)
{
	atf_tc_set_md_var(tc, "descr", "Checks EVFILT_WRITE for fifo");
}
ATF_TC_BODY(fifo, tc)
{
	char buffer[128];
	struct kevent event[1];
	pid_t child;
	int kq, n, fd, status;

	RL(mkfifo(FIFONAME, 0644));
	RL(fd = open(FIFONAME, O_RDWR, 0644));
	RL(kq = kqueue());

	/* spawn child reader */
	RL(child = fork());
	if (child == 0) {
		int sz = read(fd, buffer, 128);
		if (sz > 0)
			(void)printf("fifo: child read '%.*s'\n", sz, buffer);
		_exit(sz <= 0);
	}

	EV_SET(&event[0], fd, EVFILT_WRITE, EV_ADD|EV_ENABLE, 0, 0, 0);
	RL(kevent(kq, event, 1, NULL, 0, NULL));

	(void)memset(event, 0, sizeof(event));
	RL(n = kevent(kq, NULL, 0, event, 1, NULL));

	(void)printf("kevent num %d filt %d flags: %#x, fflags: %#x, "
	    "data: %" PRId64 "\n", n, event[0].filter, event[0].flags,
	    event[0].fflags, event[0].data);

	ATF_REQUIRE_EQ(event[0].filter, EVFILT_WRITE);

	RL(write(fd, "foo", 3));
	(void)printf("fifo: wrote 'foo'\n");
	RL(close(fd));

	(void)waitpid(child, &status, 0);
}

ATF_TP_ADD_TCS(tp)
{
	ATF_TP_ADD_TC(tp, fifo);

	return atf_no_error();
}