/*
 * Copyright (c) 2000 Kungliga Tekniska Högskolan
 * (Royal Institute of Technology, Stockholm, Sweden).
 * 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.
 * 
 * 3. Neither the name of the Institute nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE 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 INSTITUTE 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.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>

#include <err.h>
#include <roken.h>

RCSID("$KTH: truncate.c,v 1.2 2000/10/03 00:36:26 lha Exp $");

static void
create_and_write (char *name, const char *buf)
{
    int fd, ret;
    int len = strlen(buf);

    fd = open (name, O_WRONLY|O_CREAT|O_TRUNC, 0666);
    if (fd < 0)
	err (1, "open");
    ret = write (fd, buf, len);
    if (ret != len)
	err (1, "write");
    ret = close (fd);
    if (ret < 0)
	err (1, "close");
}

static void
check_size (char *name, int len)
{
    struct stat sb;
    int ret;

    ret = stat(name, &sb);
    if (ret < 0)
	err (1, "stat");

    if (len != sb.st_size)
	errx (1, "len != sb.st_size");
}

int
main(int argc, char **argv)
{
    int ret;

    set_progname (argv[0]);

    create_and_write ("foo", "hej\n");

    ret = truncate ("foo", 0);
    if (ret < 0)
	err (1, "truncate(0)");

    check_size ("foo", 0);

    ret = unlink("foo");
    if (ret < 0)
	errx (1, "unlink");

    create_and_write ("bar", "hej\nhej\n");

    ret = truncate ("bar", 16);
    if (ret < 0)
	err (1, "truncate(16)");

    check_size ("bar", 16);

    ret = unlink("bar");
    if (ret < 0)
	errx (1, "unlink");

    return 0;
}