1 /* $NetBSD: _wcstod.h,v 1.1 2006/04/15 12:17:23 tnozaki Exp $ */
2
3 /*-
4 * Copyright (c) 2002 Tim J. Robbins
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 * Original version ID:
29 * FreeBSD: /repoman/r/ncvs/src/lib/libc/locale/wcstod.c,v 1.4 2004/04/07 09:47:56 tjr Exp
30 * NetBSD: wcstod.c,v 1.8 2006/04/13 01:25:13 tnozaki Exp
31 */
32
33 /*
34 * function template for wcstof, wcstod, wcstold.
35 *
36 * parameters:
37 * _FUNCNAME : function name
38 * _RETURN_TYPE : return type
39 * _STRTOD_FUNC : real conversion function
40 */
41 #ifndef __WCSTOD_H_
42 #define __WCSTOD_H_
43
44 /*
45 * Convert a string to a double-precision number.
46 *
47 * This is the wide-character counterpart of strto{f,d,ld}(). So that
48 * we do not have to duplicate the code of strto{f,d,ld}() here,
49 * we convert the supplied wide character string to multibyte and
50 * call strto{f,d,ld}() on the result.
51 * This assumes that the multibyte encoding is compatible with ASCII
52 * for at least the digits, radix character and letters.
53 */
54 _RETURN_TYPE
_FUNCNAME(const wchar_t * __restrict nptr,wchar_t ** __restrict endptr)55 _FUNCNAME(const wchar_t * __restrict nptr, wchar_t ** __restrict endptr)
56 {
57 const wchar_t *src, *start;
58 _RETURN_TYPE val;
59 char *buf, *end;
60 size_t bufsiz, len;
61
62 _DIAGASSERT(nptr != NULL);
63 /* endptr may be null */
64
65 src = nptr;
66 while (iswspace((wint_t)*src) != 0)
67 ++src;
68 if (*src == L'\0')
69 goto no_convert;
70
71 /*
72 * Convert the supplied numeric wide char. string to multibyte.
73 *
74 * We could attempt to find the end of the numeric portion of the
75 * wide char. string to avoid converting unneeded characters but
76 * choose not to bother; optimising the uncommon case where
77 * the input string contains a lot of text after the number
78 * duplicates a lot of strto{f,d,ld}()'s functionality and
79 * slows down the most common cases.
80 */
81 start = src;
82 len = wcstombs(NULL, src, 0);
83 if (len == (size_t)-1)
84 /* errno = EILSEQ */
85 goto no_convert;
86
87 _DIAGASSERT(len > 0);
88
89 bufsiz = len;
90 buf = (void *)malloc(bufsiz + 1);
91 if (buf == NULL)
92 /* errno = ENOMEM */
93 goto no_convert;
94
95 len = wcstombs(buf, src, bufsiz + 1);
96
97 _DIAGASSERT(len == bufsiz);
98 _DIAGASSERT(buf[len] == '\0');
99
100 /* Let strto{f,d,ld}() do most of the work for us. */
101 val = _STRTOD_FUNC(buf, &end);
102 if (buf == end) {
103 free(buf);
104 goto no_convert;
105 }
106
107 /*
108 * We only know where the number ended in the _multibyte_
109 * representation of the string. If the caller wants to know
110 * where it ended, count multibyte characters to find the
111 * corresponding position in the wide char string.
112 */
113 if (endptr != NULL)
114 /* XXX Assume each wide char is one byte. */
115 *endptr = __UNCONST(start + (size_t)(end - buf));
116
117 free(buf);
118
119 return val;
120
121 no_convert:
122 if (endptr != NULL)
123 *endptr = __UNCONST(nptr);
124 return 0.0;
125 }
126 #endif /*__WCSTOD_H_*/
127