xref: /freebsd/contrib/mandoc/compat_strtonum.c (revision b97ee269eae3cbaf35c18f51a459aea581c2a7dc)
1 /*	$Id: compat_strtonum.c,v 1.2 2020/06/15 01:37:15 schwarze Exp $	*/
2 /*	$OpenBSD: strtonum.c,v 1.8 2015/09/13 08:31:48 guenther Exp $	*/
3 
4 /*
5  * Copyright (c) 2004 Ted Unangst and Todd Miller
6  * All rights reserved.
7  *
8  * Permission to use, copy, modify, and distribute this software for any
9  * purpose with or without fee is hereby granted, provided that the above
10  * copyright notice and this permission notice appear in all copies.
11  *
12  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
13  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
14  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
15  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
16  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
17  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
18  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
19  */
20 #include "config.h"
21 
22 #include <errno.h>
23 #include <limits.h>
24 #include <stdlib.h>
25 
26 #define	INVALID		1
27 #define	TOOSMALL	2
28 #define	TOOLARGE	3
29 
30 long long
31 strtonum(const char *numstr, long long minval, long long maxval,
32     const char **errstrp)
33 {
34 	long long ll = 0;
35 	int error = 0;
36 	char *ep;
37 	struct errval {
38 		const char *errstr;
39 		int err;
40 	} ev[4] = {
41 		{ NULL,		0 },
42 		{ "invalid",	EINVAL },
43 		{ "too small",	ERANGE },
44 		{ "too large",	ERANGE },
45 	};
46 
47 	ev[0].err = errno;
48 	errno = 0;
49 	if (minval > maxval) {
50 		error = INVALID;
51 	} else {
52 		ll = strtoll(numstr, &ep, 10);
53 		if (numstr == ep || *ep != '\0')
54 			error = INVALID;
55 		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
56 			error = TOOSMALL;
57 		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
58 			error = TOOLARGE;
59 	}
60 	if (errstrp != NULL)
61 		*errstrp = ev[error].errstr;
62 	errno = ev[error].err;
63 	if (error)
64 		ll = 0;
65 
66 	return (ll);
67 }
68