xref: /netbsd-src/lib/libc/locale/wcstod.c (revision 8a8f936f250a330d54f8a24ed0e92aadf9743a7b)
1 /* $NetBSD: wcstod.c,v 1.3 2001/10/02 01:20:03 erh Exp $ */
2 
3 /*-
4  * Copyright (c)1999, 2000, 2001 Citrus Project,
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  *	$Citrus: xpg4dl/FreeBSD/lib/libc/locale/wcstod.c,v 1.2 2001/09/27 16:23:57 yamt Exp $
29  */
30 
31 #include <sys/cdefs.h>
32 #include <assert.h>
33 #include <errno.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <wchar.h>
37 #include <wctype.h>
38 
39 /* XXX our lint can't handle wide char constant */
40 #if defined(lint)
41 #define _L(x) ((const wchar_t *)0)
42 #define _LC(x) ((wchar_t)0)
43 #else
44 #define _L(x) __CONCAT(L,x)
45 #define _LC(x) __CONCAT(L,x)
46 #endif
47 
48 double
49 wcstod(const wchar_t *nptr, wchar_t **endptr)
50 {
51 	const wchar_t *src;
52 	size_t size;
53 	const wchar_t *start;
54 
55 	_DIAGASSERT(nptr);
56 
57 	/*
58 	 * we do only check length of string
59 	 * and give it over strtod.
60 	 */
61 	src = nptr;
62 
63 	/* skip space first */
64 	while (iswspace(*src)) {
65 		src++;
66 	}
67 
68 	/* get length of string */
69 	start = src;
70 	if (wcschr(_L("+-"), *src))
71 		src++;
72 	size = wcsspn(src, _L("0123456789"));
73 	src += size;
74 	if (*src == _LC('.')) {/* XXX use localeconv */
75 		src++;
76 		size = wcsspn(src, _L("0123456789"));
77 		src += size;
78 	}
79 	if (wcschr(_L("Ee"), *src)) {
80 		src++;
81 		if (wcschr(_L("+-"), *src))
82 			src++;
83 		size = wcsspn(src, _L("0123456789"));
84 		src += size;
85 	}
86 	size = src - start;
87 
88 	/*
89 	 * convert to a char-string and pass it to strtod.
90 	 *
91 	 * since all chars used to represent a double-constant
92 	 * are in the portable character set, we can assume
93 	 * that they are 1-byte chars.
94 	 */
95 	if (size)
96 	{
97 		mbstate_t st;
98 		char *buf;
99 		char *end;
100 		const wchar_t *s;
101 		size_t size_converted;
102 		double result;
103 
104 		buf = malloc(size + 1);
105 		if (!buf) {
106 			/* error */
107 			errno = ENOMEM; /* XXX */
108 			return 0;
109 		}
110 
111 		s = start;
112 		memset(&st, 0, sizeof(st));
113 		size_converted = wcsrtombs(buf, &s, size, &st);
114 		if (size != size_converted) {
115 			/* XXX should not happen */
116 			free(buf);
117 			errno = EILSEQ;
118 			return 0;
119 		}
120 
121 		buf[size] = 0;
122 		result = strtod(buf, &end);
123 
124 		free(buf);
125 
126 		if (endptr)
127 			/* LINTED bad interface */
128 			*endptr = (wchar_t*)start + (end - buf);
129 
130 		return result;
131 	}
132 
133 	if (endptr)
134 		/* LINTED bad interface */
135 		*endptr = (wchar_t*)start;
136 
137 	return 0;
138 }
139