/*	$NetBSD: t_sendrecv.c,v 1.8 2021/03/28 17:30:01 christos Exp $	*/

/*-
 * Copyright (c) 2018 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Christos Zoulas.
 *
 * 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: t_sendrecv.c,v 1.8 2021/03/28 17:30:01 christos Exp $");

#include <atf-c.h>
#include <sys/types.h>
#include <sys/socket.h>

#include <string.h>
#include <stdint.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <sched.h>
#include <unistd.h>
#include <signal.h>


#define COUNT 100

union packet {
	uint8_t buf[1316];
	uintmax_t seq;
};

static volatile sig_atomic_t rdied;

static void
handle_sigchld(__unused int pid)
{

	rdied = 1;
}

static void
sender(int sd)
{
	union packet p;
	ssize_t n;
	p.seq = 0;
	for (size_t i = 0; i < COUNT; i++) {
		for (; (n = send(sd, &p, sizeof(p), 0)) == sizeof(p);
		    p.seq++)
			continue;
//		printf(">>%zd %d %ju\n", n, errno, p.seq);
		ATF_REQUIRE_MSG(errno == ENOBUFS, "send %s", strerror(errno));
	}
	close(sd);
//	printf("sender done\n");
}

static void
receiver(int sd)
{
	union packet p;
	ssize_t n;
	uintmax_t seq = 0;

	for (size_t i = 0; i < COUNT; i++) {
		if (rdied)
			return;
		while ((n = recv(sd, &p, sizeof(p), 0), sizeof(p))
		    == sizeof(p))
		{
			if (rdied)
				return;
			if (p.seq != seq)
				printf("%ju != %ju\n", p.seq, seq);
			if (seq % 10 == 0)
				sched_yield();
			seq = p.seq + 1;
		}
//		printf("<<%zd %d %ju\n", n, errno, seq);
		if (n == 0)
			return;
		ATF_REQUIRE_EQ(n, -1);
		ATF_REQUIRE_MSG(errno == ENOBUFS, "recv %s", strerror(errno));
	}
	close(sd);
}

static void
sendrecv(int rerror)
{
	int fd[2], sd[2], error;
	char c = 0;
	struct sigaction sa;

	error = socketpair(AF_UNIX, SOCK_DGRAM, 0, sd);
	ATF_REQUIRE_MSG(error != -1, "socketpair failed (%s)", strerror(errno));
	error = pipe(fd);
	ATF_REQUIRE_MSG(error != -1, "pipe failed (%s)", strerror(errno));

	for (size_t i = 0; i < __arraycount(sd); i++) {
		error = setsockopt(sd[i], SOL_SOCKET, SO_RERROR, &rerror,
		    sizeof(rerror));
		ATF_REQUIRE_MSG(error != -1,
		    "setsockopt(SO_RERROR) failed (%s)", strerror(errno));
	}

	memset(&sa, 0, sizeof(sa));
	sa.sa_flags = 0;
	sa.sa_handler = &handle_sigchld;
	sigemptyset(&sa.sa_mask);
	error = sigaction(SIGCHLD, &sa, 0);
	ATF_REQUIRE_MSG(error != -1, "sigaction failed (%s)",
	    strerror(errno));

	switch (fork()) {
	case -1:
		ATF_REQUIRE_MSG(errno == 0,
		    "fork failed (%s)", strerror(errno));
		__unreachable();
		/*NOTREACHED*/
	case 0:
		read(fd[1], &c, sizeof(c));
		sender(sd[0]);
		close(sd[0]);
		exit(EXIT_SUCCESS);
		/*NOTREACHED*/
	default:
		write(fd[0], &c, sizeof(c));
		receiver(sd[1]);
		return;
	}
}

ATF_TC(sendrecv_basic);

ATF_TC_HEAD(sendrecv_basic, tc)
{
	atf_tc_set_md_var(tc, "descr", "A basic test of send/recv(2)");
}

ATF_TC_BODY(sendrecv_basic, tc)
{
	sendrecv(0);
}

ATF_TC(sendrecv_rerror);

ATF_TC_HEAD(sendrecv_rerror, tc)
{
	atf_tc_set_md_var(tc, "descr", "Test send/recv(2) with receiver error");
}

ATF_TC_BODY(sendrecv_rerror, tc)
{
	sendrecv(1);
}

ATF_TP_ADD_TCS(tp)
{

	ATF_TP_ADD_TC(tp, sendrecv_basic);
	ATF_TP_ADD_TC(tp, sendrecv_rerror);

	return atf_no_error();
}