/*      $OpenBSD: malloc_ulimit1.c,v 1.6 2025/05/24 06:47:27 otto Exp $ */

/* Public Domain, 2006, Otto Moerbeek <otto@drijf.net> */

#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <err.h>
#include <stdlib.h>
#include <stdio.h>

/*
 * This code tries to trigger the case present in -current as of April
 * 2006) where the allocation of the region itself succeeds, but the
 * page dir entry pages fails.
 * This in turn trips a "hole in directories" error.
 * Having a large (512M) ulimit -m helps a lot in triggering the
 * problem. Note that you may need to run this test multiple times to
 * see the error.
*/

#define STARTI  1300
#define FACTOR  1024

/* This test takes forever with junking turned on. */
const char * const malloc_options = "jj";

int
main()
{
        struct rlimit lim;
        size_t sz;
        int i;
        void *p;

        if (getrlimit(RLIMIT_DATA, &lim) == -1)
                err(1, "getrlimit");

        sz = lim.rlim_cur / FACTOR;

        for (i = STARTI; i >= 0; i--) {
                size_t len = (sz-i) * FACTOR;
                p = malloc(len);
                free(p);
                free(malloc(4096));
        }
        return (0);
}