/*
 * Copyright (c) 2006 Darren Tucker
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"

#include <sys/types.h>
#include <sys/stat.h>

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

#define NUM_OPENS 10

void
fail(char *msg)
{
        fprintf(stderr, "closefrom: %s\n", msg);
        exit(1);
}

int
main(void)
{
        int i, max, fds[NUM_OPENS];
        char buf[512];

        for (i = 0; i < NUM_OPENS; i++)
                if ((fds[i] = open("/dev/null", O_RDONLY)) == -1)
                        exit(0);        /* can't test */
        max = i - 1;

        /* should close last fd only */
        closefrom(fds[max]);
        if (close(fds[max]) != -1)
                fail("failed to close highest fd");

        /* make sure we can still use remaining descriptors */
        for (i = 0; i < max; i++)
                if (read(fds[i], buf, sizeof(buf)) == -1)
                        fail("closed descriptors it should not have");

        /* should close all fds */
        closefrom(fds[0]);
        for (i = 0; i < NUM_OPENS; i++)
                if (close(fds[i]) != -1)
                        fail("failed to close from lowest fd");
        return 0;
}