1/*-
2 * Copyright (c) 2004 Ted Unangst and Todd Miller
3 * All rights reserved.
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 *	$OpenBSD: strtonum.c,v 1.7 2013/04/17 18:40:58 tedu Exp $
18 */
19
20#include <errno.h>
21#include <limits.h>
22#include <stdlib.h>
23
24#define	INVALID		1
25#define	TOOSMALL	2
26#define	TOOLARGE	3
27
28long long
29strtonum(const char *numstr, long long minval, long long maxval,
30    const char **errstrp)
31{
32	long long ll = 0;
33	int error = 0;
34	char *ep;
35	struct errval {
36		const char *errstr;
37		int err;
38	} ev[4] = {
39		{ NULL,		0 },
40		{ "invalid",	EINVAL },
41		{ "too small",	ERANGE },
42		{ "too large",	ERANGE },
43	};
44
45	ev[0].err = errno;
46	errno = 0;
47	if (minval > maxval) {
48		error = INVALID;
49	} else {
50		ll = strtoll(numstr, &ep, 10);
51		if (errno == EINVAL || numstr == ep || *ep != '\0')
52			error = INVALID;
53		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
54			error = TOOSMALL;
55		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
56			error = TOOLARGE;
57	}
58	if (errstrp != NULL)
59		*errstrp = ev[error].errstr;
60	errno = ev[error].err;
61	if (error)
62		ll = 0;
63
64	return (ll);
65}
66