xref: /dragonfly/lib/libc/stdlib/strtonum.c (revision 19fe1c42)
1 /* $DragonFly: src/lib/libc/stdlib/strtonum.c,v 1.2 2006/09/28 17:20:45 corecode Exp $ */
2 /*	$OpenBSD: strtonum.c,v 1.6 2004/08/03 19:38:01 millert 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 
21 #include <errno.h>
22 #include <limits.h>
23 #include <stdlib.h>
24 
25 #define INVALID 	1
26 #define TOOSMALL 	2
27 #define TOOLARGE 	3
28 
29 long long
30 strtonum(const char *numstr, long long minval, long long maxval,
31     const char **errstrp)
32 {
33 	long long ll = 0;
34 	char *ep;
35 	int error = 0;
36 	struct errval {
37 		const char *errstr;
38 		int err;
39 	} ev[4] = {
40 		{ NULL,		0 },
41 		{ "invalid",	EINVAL },
42 		{ "too small",	ERANGE },
43 		{ "too large",	ERANGE },
44 	};
45 
46 	ev[0].err = errno;
47 	errno = 0;
48 	if (minval > maxval)
49 		error = INVALID;
50 	else {
51 		ll = strtoll(numstr, &ep, 10);
52 		if (numstr == ep || *ep != '\0')
53 			error = INVALID;
54 		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
55 			error = TOOSMALL;
56 		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
57 			error = TOOLARGE;
58 	}
59 	if (errstrp != NULL)
60 		*errstrp = ev[error].errstr;
61 	errno = ev[error].err;
62 	if (error)
63 		ll = 0;
64 
65 	return (ll);
66 }
67