/*
 * Copyright (c) 2003-2004 Daichi GOTO <daichi@ongs.co.jp>
 * 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/types.h>
#include <sys/event.h>

#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <sysexits.h>
#include <time.h>

#define kevent_add(kq, ev) kevent((kq), (ev), 1, NULL, 0, NULL)
#define kevent_poll(kq, ev) kevent((kq), NULL, 0, (ev), 1, NULL)

static void     usage(void);
static void     addwatchfile(int, int);
static void     watchfile(int);

int
main(int argc, char *argv[])
{
	int             kq;
	int             filedesc;
	int             count;

	if (2 > argc) {
		usage();
		exit(EX_USAGE);
	}

	kq = kqueue();

	for (count = 1; count < argc; count++) {
		filedesc = open(argv[count], O_RDONLY);
		if (-1 == filedesc) {
			fprintf(stderr,
				"error: cannot open file: %d\n", errno);
			exit(EX_NOINPUT);
		}
		addwatchfile(kq, filedesc);
	}

	watchfile(kq);

	exit(EX_OK);
}

static void
usage(void)
{
	fprintf(stderr, "usage: fwatch files...\n");
}

static void
addwatchfile(int kq, int filedesc)
{
	struct kevent   event;

	EV_SET(&event, filedesc,
	       EVFILT_VNODE,
	       EV_ADD | EV_ENABLE | EV_CLEAR,
	       NOTE_DELETE | NOTE_WRITE | NOTE_EXTEND | NOTE_ATTRIB | NOTE_RENAME, 0, 0);

	kevent_add(kq, &event);
}

static void
watchfile(int kq)
{
	struct kevent   event;

	kevent_poll(kq, &event);
}