/*-
 * Copyright (c) 2011 Advanced Computing Technologies LLC
 * Written by: John H. Baldwin <jhb@FreeBSD.org>
 * 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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

/*
 * Test application for /dev/memfd demo driver.
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <assert.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <unistd.h>

static void *
mapmem(int fd, off_t offset, size_t length)
{
	void *p;

	p = mmap(NULL, length, PROT_READ | PROT_WRITE, MAP_SHARED, fd, offset);
	if (p == MAP_FAILED)
		err(1, "mmap");
	return (p);
}

static void
unmapmem(void *addr, size_t len)
{

	if (munmap(addr, len) < 0)
		err(1, "munmap");
}

static int
openmem(void)
{
	int fd;

	fd = open("/dev/memfd", O_RDWR);
	if (fd < 0)
		err(1, "open(\"/dev/memfd/");
	return (fd);
}

int
main(int ac, char **av)
{
	char *p, *q, *p2;
	int fd, fd2;

	/* Test invalid open requests. */
	fd = open("/dev/memfd", O_RDONLY);
	assert(fd == -1);
	fd = open("/dev/memfd", O_WRONLY);
	assert(fd == -1);

	/* Allocate a single page. */
	fd = openmem();
	p = mapmem(fd, 0, getpagesize());
	p[16] = 1;

	/* Grow to two pages. */
	q = mapmem(fd, getpagesize(), getpagesize());

	/* Ensure p and q are different pages. */
	assert(p[16] == 1);
	assert(q[16] == 0);
	q[16] = 2;

	/* Make p map both pages, p's second page should shadow q. */
	unmapmem(p, getpagesize());
	p = mapmem(fd, 0, getpagesize() * 2);
	assert(p[16] == 1);
	assert(p[16 + getpagesize()] == 2);
	p[getpagesize()] = 3;
	assert(q[0] == 3);

	/* Open a second instance, should be completely separate. */
	fd2 = openmem();
	p2 = mapmem(fd2, 0, getpagesize() * 2);
	assert(p2[16] == 0);
	assert(p2[getpagesize()] == 0);
	assert(p2[16 + getpagesize()] == 0);
	p2[8] = 4;
	assert(p[8] == 0);
	p[8] = 5;
	assert(p2[8] == 4);
	unmapmem(p2, getpagesize() * 2);
	close(fd2);

	/*
	 * Unmap original object completely and then remap it.  Data
	 * should be preserved.
	 */
	unmapmem(q, getpagesize());
	unmapmem(p, getpagesize() * 2);
	p = mapmem(fd, 0, getpagesize() * 2);
	assert(p[0] == 0);
	assert(p[16] == 1);
	assert(p[16 + getpagesize()] == 2);
	assert(p[getpagesize()] == 3);
	assert(p[8] == 5);

	close(fd);
	printf("memfd tests passed\n");

	return (0);
}