xref: /illumos-gate/usr/src/lib/libc/port/gen/strtonum.c (revision 4585130b259133a26efae68275dbe56b08366deb)
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 
18 #include <errno.h>
19 #include <limits.h>
20 #include <stdlib.h>
21 
22 #define	INVALID		1
23 #define	TOOSMALL	2
24 #define	TOOLARGE	3
25 
26 long long
27 strtonum(const char *numstr, long long minval, long long maxval,
28     const char **errstrp)
29 {
30 	long long ll = 0;
31 	int error = 0;
32 	char *ep;
33 	struct errval {
34 		const char *errstr;
35 		int err;
36 	} ev[4] = {
37 		{ NULL,		0 },
38 		{ "invalid",	EINVAL },
39 		{ "too small",	ERANGE },
40 		{ "too large",	ERANGE },
41 	};
42 
43 	ev[0].err = errno;
44 	errno = 0;
45 	if (minval > maxval) {
46 		error = INVALID;
47 	} else {
48 		ll = strtoll(numstr, &ep, 10);
49 		if (numstr == ep || *ep != '\0')
50 			error = INVALID;
51 		else if ((ll == LLONG_MIN && errno == ERANGE) || ll < minval)
52 			error = TOOSMALL;
53 		else if ((ll == LLONG_MAX && errno == ERANGE) || ll > maxval)
54 			error = TOOLARGE;
55 	}
56 	if (errstrp != NULL)
57 		*errstrp = ev[error].errstr;
58 	errno = ev[error].err;
59 	if (error)
60 		ll = 0;
61 
62 	return (ll);
63 }
64