1/*-
2 * Copyright (c) 2016 The FreeBSD Foundation
3 * All rights reserved.
4 *
5 * This software was developed by Ed Maste under sponsorship
6 * of the FreeBSD Foundation.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <errno.h>
31#include <stdlib.h>
32#include <time.h>
33#include <libelftc.h>
34
35int
36elftc_timestamp(time_t *timestamp)
37{
38	long long source_date_epoch;
39	char *env, *eptr;
40
41	if ((env = getenv("SOURCE_DATE_EPOCH")) != NULL) {
42		errno = 0;
43		source_date_epoch = strtoll(env, &eptr, 10);
44		if (*eptr != '\0')
45			errno = EINVAL;
46		if (source_date_epoch < 0)
47			errno = ERANGE;
48		if (errno != 0)
49			return (-1);
50		*timestamp = source_date_epoch;
51		return (0);
52	}
53	*timestamp = time(NULL);
54	return (0);
55}
56