wcstol.c revision 1219:f89f56c2d9ac 
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22
23/*
24 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
25 * Use is subject to license terms.
26 */
27
28#pragma ident	"%Z%%M%	%I%	%E% SMI"
29
30/*	Copyright (c) 1986 AT&T	*/
31/*	  All Rights Reserved  	*/
32
33
34#ifndef	_WCS_LONGLONG
35#pragma weak wcstol = _wcstol
36#endif
37
38#include "synonyms.h"
39#include <limits.h>
40#include <errno.h>
41#include <wchar.h>
42#define	DIGIT(x)	(iswdigit(x) ? (x) - L'0' : \
43			iswlower(x) ? (x) + 10 - L'a' : (x) + 10 - L'A')
44#define	MBASE	(L'z' - L'a' + 1 + 10)
45
46#ifdef	_WCS_LONGLONG
47#define	_WLONG_T	long long
48#define	_WLONG_MAX	LLONG_MAX
49#define	_WLONG_MIN	LLONG_MIN
50#else  /* _WCS_LONGLONG */
51#define	_WLONG_T	long
52#define	_WLONG_MAX	LONG_MAX
53#define	_WLONG_MIN	LONG_MIN
54#endif /* _WCS_LONGLONG */
55
56#ifdef	_WCS_LONGLONG
57long long
58wcstoll(const wchar_t *_RESTRICT_KYWD str, wchar_t **_RESTRICT_KYWD ptr,
59    int base)
60#else  /* _WCS_LONGLONG */
61long
62_wcstol(const wchar_t *str, wchar_t **ptr, int base)
63#endif /* _WCS_LONGLONG */
64{
65	_WLONG_T	val;
66	wchar_t	c;
67	int	xx, neg = 0;
68	_WLONG_T	multmin, limit;
69
70	if (ptr != NULL)
71		*ptr = (wchar_t *)str; /* in case no number is formed */
72	if (base < 0 || base > MBASE) {
73		errno = EINVAL;
74		return (0); /* base is invalid -- should be a fatal error */
75	}
76
77	if (!iswalnum(c = *str)) {
78		while (iswspace(c)) {
79			c = *++str;
80		}
81		switch (c) {
82		case L'-':
83			neg++;
84			/*FALLTHRU*/
85		case L'+':
86			c = *++str;
87		}
88	}
89	if (base == 0) {
90		if (c != L'0')
91			base = 10;
92		else if (str[1] == L'x' || str[1] == L'X')
93			base = 16;
94		else
95			base = 8;
96	}
97	/*
98	 * for any base > 10, the digits incrementally following
99	 *	9 are assumed to be "abc...z" or "ABC...Z"
100	 */
101	if (!iswalnum(c) || (xx = DIGIT(c)) >= base) {
102		errno = EINVAL;
103		return (0); /* no number formed */
104	}
105
106	if (base == 16 && c == L'0' && iswxdigit(str[2]) &&
107	    (str[1] == L'x' || str[1] == L'X')) {
108		c = *(str += 2); /* skip over leading "0x" or "0X" */
109	}
110
111	if (neg) {
112		limit = _WLONG_MIN;
113	} else {
114		limit = -_WLONG_MAX;
115	}
116	multmin = limit / base;
117
118	val = -DIGIT(c);
119	for (; iswalnum(c = *++str) && (xx = DIGIT(c)) < base; ) {
120		/* accumulate neg avoids surprises near MAXLONG */
121		if (val < multmin)
122			goto overflow;
123		val *= base;
124		if (val < limit + xx)
125			goto overflow;
126		val -= xx;
127	}
128	if (ptr != NULL)
129		*ptr = (wchar_t *)str;
130	return (neg ? val : -val);
131
132overflow:
133	while (iswalnum(c = *++str) && (xx = DIGIT(c)) < base)
134		;
135
136	if (ptr != NULL)
137		*ptr = (wchar_t *)str;
138	errno = ERANGE;
139	return (neg ? _WLONG_MIN : _WLONG_MAX);
140}
141