xref: /netbsd-src/lib/libc/locale/wcstol.c (revision 9fbd88883c38d0c0fbfcbe66d76fe6b0fab3f9de)
1 /*	$NetBSD: wcstol.c,v 1.1 2001/09/27 16:30:36 yamt Exp $	*/
2 /* $Citrus: xpg4dl/FreeBSD/lib/libc/locale/wcstol.c,v 1.2 2001/09/21 16:11:41 yamt Exp $ */
3 
4 /*-
5  * Copyright (c) 1990, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *    must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 #if 0
40 static char sccsid[] = "@(#)strtol.c	8.1 (Berkeley) 6/4/93";
41 #else
42 __RCSID("$NetBSD: wcstol.c,v 1.1 2001/09/27 16:30:36 yamt Exp $");
43 #endif
44 #endif /* LIBC_SCCS and not lint */
45 
46 #include <assert.h>
47 #include <ctype.h>
48 #include <errno.h>
49 #include <limits.h>
50 #include <stdlib.h>
51 #include <wchar.h>
52 #include <wctype.h>
53 
54 #include "__wctoint.h"
55 
56 /*
57  * Convert a wide-char string to a long integer.
58  */
59 long
60 wcstol(nptr, endptr, base)
61 	const wchar_t *nptr;
62 	wchar_t **endptr;
63 	int base;
64 {
65 	const wchar_t *s;
66 	long acc, cutoff;
67 	wint_t wc;
68 	int i;
69 	int neg, any, cutlim;
70 
71 	_DIAGASSERT(nptr != NULL);
72 	/* endptr may be NULL */
73 
74 	/* check base value */
75 	if (base && (base < 2 || base > 36)) {
76 		errno = EINVAL;
77 		return 0;
78 	}
79 
80 	/*
81 	 * Skip white space and pick up leading +/- sign if any.
82 	 * If base is 0, allow 0x for hex and 0 for octal, else
83 	 * assume decimal; if base is already 16, allow 0x.
84 	 */
85 	s = nptr;
86 	do {
87 		wc = (wchar_t) *s++;
88 	} while (iswspace(wc));
89 	if (wc == L'-') {
90 		neg = 1;
91 		wc = *s++;
92 	} else {
93 		neg = 0;
94 		if (wc == L'+')
95 			wc = *s++;
96 	}
97 	if ((base == 0 || base == 16) &&
98 	    wc == L'0' && (*s == L'x' || *s == L'X')) {
99 		wc = s[1];
100 		s += 2;
101 		base = 16;
102 	}
103 	if (base == 0)
104 		base = wc == '0' ? 8 : 10;
105 
106 	/*
107 	 * Compute the cutoff value between legal numbers and illegal
108 	 * numbers.  That is the largest legal value, divided by the
109 	 * base.  An input number that is greater than this value, if
110 	 * followed by a legal input character, is too big.  One that
111 	 * is equal to this value may be valid or not; the limit
112 	 * between valid and invalid numbers is then based on the last
113 	 * digit.  For instance, if the range for longs is
114 	 * [-2147483648..2147483647] and the input base is 10,
115 	 * cutoff will be set to 214748364 and cutlim to either
116 	 * 7 (neg==0) or 8 (neg==1), meaning that if we have accumulated
117 	 * a value > 214748364, or equal but the next digit is > 7 (or 8),
118 	 * the number is too big, and we will return a range error.
119 	 *
120 	 * Set any if any `digits' consumed; make it negative to indicate
121 	 * overflow.
122 	 */
123 	cutoff = neg ? LONG_MIN : LONG_MAX;
124 	cutlim = (int)(cutoff % base);
125 	cutoff /= base;
126 	if (neg) {
127 		if (cutlim > 0) {
128 			cutlim -= base;
129 			cutoff += 1;
130 		}
131 		cutlim = -cutlim;
132 	}
133 	for (acc = 0, any = 0;; wc = (wchar_t) *s++) {
134 		i = __wctoint(wc);
135 		if (i == -1)
136 			break;
137 		if (i >= base)
138 			break;
139 		if (any < 0)
140 			continue;
141 		if (neg) {
142 			if (acc < cutoff || (acc == cutoff && i > cutlim)) {
143 				any = -1;
144 				acc = LONG_MIN;
145 				errno = ERANGE;
146 			} else {
147 				any = 1;
148 				acc *= base;
149 				acc -= i;
150 			}
151 		} else {
152 			if (acc > cutoff || (acc == cutoff && i > cutlim)) {
153 				any = -1;
154 				acc = LONG_MAX;
155 				errno = ERANGE;
156 			} else {
157 				any = 1;
158 				acc *= base;
159 				acc += i;
160 			}
161 		}
162 	}
163 	if (endptr != 0)
164 		/* LINTED interface specification */
165 		*endptr = (wchar_t *)(any ? s - 1 : nptr);
166 	return (acc);
167 }
168