xref: /titanic_50/usr/src/cmd/cmd-inet/usr.bin/nc/strtonum.c (revision c7158ae983f5a04c4a998f468ecefba6d23ba721)
1 /*	$OpenBSD: strtonum.c,v 1.6 2004/08/03 19:38:01 millert Exp $	*/
2 
3 /*
4  * Copyright (c) 2004 Ted Unangst and Todd Miller
5  * All rights reserved.
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #pragma ident	"%Z%%M%	%I%	%E% SMI"
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 unsigned int
31 strtonum(const char *numstr, unsigned int minval, unsigned int maxval,
32     const char **errstrp)
33 {
34 	long long ll = 0;
35 	char *ep;
36 	int error = 0;
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 	/*
67 	 * we have already checked boundaries above so we can safely
68 	 * convert return type here
69 	 */
70 	return ((unsigned int)ll);
71 }
72