/*      $OpenBSD: mmap_fixed.c,v 1.3 2016/08/27 04:35:19 guenther Exp $ */

/*
 * Public domain. 2006, Kurt Miller <kurt@intricatesoftware.com>
 */

#include <sys/types.h>
#include <sys/mman.h>
#include <err.h>
#include <stdio.h>

#define MEM_SIZE        1024*1024

/*
 * Repetitively call mmap with MMAP_FIXED on the same region of memory
 * to ensure process datasize is properly calculated.
 */

int
main(void)
{
        void *mem_area;
        int i;

        mem_area = mmap(0, MEM_SIZE, PROT_NONE, MAP_ANON, -1, 0);

        for (i = 0; i < 20000; i++) {
                if (mmap(mem_area, MEM_SIZE, PROT_READ|PROT_WRITE,
                    MAP_ANON|MAP_FIXED, -1, 0) == MAP_FAILED)
                        err(1, NULL);
        }

        return (0);
}