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 #include "config.h"
18 
19 #include <errno.h>
20 #include <limits.h>
21 #include <stdlib.h>
22 
23 #define	INVALID		1
24 #define	TOOSMALL	2
25 #define	TOOLARGE	3
26 
27 long long
28 strtonum(const char *numstr, long long minval, long long maxval,
29     const char **errstrp)
30 {
31 	long long ll = 0;
32 	int error = 0;
33 	char *ep;
34 	struct errval {
35 		const char *errstr;
36 		int err;
37 	} ev[4] = {
38 		{ NULL,		0 },
39 		{ "invalid",	EINVAL },
40 		{ "too small",	ERANGE },
41 		{ "too large",	ERANGE },
42 	};
43 
44 	ev[0].err = errno;
45 	errno = 0;
46 	if (minval > maxval) {
47 		error = INVALID;
48 	} else {
49 		ll = strtoll(numstr, &ep, 10);
50 		if (numstr == ep || *ep != '\0')
51 			error = INVALID;
52 		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
53 			error = TOOSMALL;
54 		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
55 			error = TOOLARGE;
56 	}
57 	if (errstrp != NULL)
58 		*errstrp = ev[error].errstr;
59 	errno = ev[error].err;
60 	if (error)
61 		ll = 0;
62 
63 	return (ll);
64 }