1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2002 Tim J. Robbins
5 * All rights reserved.
6 *
7 * Copyright (c) 2011 The FreeBSD Foundation
8 *
9 * Portions of this software were developed by David Chisnall
10 * under sponsorship from the FreeBSD Foundation.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 #include <stdlib.h>
35 #include <wchar.h>
36 #include <wctype.h>
37 #include "xlocale_private.h"
38
39 /*
40 * Convert a string to a double-precision number.
41 *
42 * This is the wide-character counterpart of strtod(). So that we do not
43 * have to duplicate the code of strtod() here, we convert the supplied
44 * wide character string to multibyte and call strtod() on the result.
45 * This assumes that the multibyte encoding is compatible with ASCII
46 * for at least the digits, radix character and letters.
47 */
48 double
wcstod_l(const wchar_t * __restrict nptr,wchar_t ** __restrict endptr,locale_t locale)49 wcstod_l(const wchar_t * __restrict nptr, wchar_t ** __restrict endptr,
50 locale_t locale)
51 {
52 static const mbstate_t initial;
53 mbstate_t mbs;
54 double val;
55 char *buf, *end;
56 const wchar_t *wcp;
57 size_t len;
58 size_t spaces;
59 FIX_LOCALE(locale);
60
61 wcp = nptr;
62 spaces = 0;
63 while (iswspace_l(*wcp, locale)) {
64 wcp++;
65 spaces++;
66 }
67
68 /*
69 * Convert the supplied numeric wide char. string to multibyte.
70 *
71 * We could attempt to find the end of the numeric portion of the
72 * wide char. string to avoid converting unneeded characters but
73 * choose not to bother; optimising the uncommon case where
74 * the input string contains a lot of text after the number
75 * duplicates a lot of strtod()'s functionality and slows down the
76 * most common cases.
77 */
78 mbs = initial;
79 if ((len = wcsrtombs_l(NULL, &wcp, 0, &mbs, locale)) == (size_t)-1) {
80 if (endptr != NULL)
81 *endptr = (wchar_t *)nptr;
82 return (0.0);
83 }
84 if ((buf = malloc(len + 1)) == NULL) {
85 if (endptr != NULL)
86 *endptr = (wchar_t *)nptr;
87 return (0.0);
88 }
89 mbs = initial;
90 wcsrtombs_l(buf, &wcp, len + 1, &mbs, locale);
91
92 /* Let strtod() do most of the work for us. */
93 val = strtod_l(buf, &end, locale);
94
95 /*
96 * We only know where the number ended in the _multibyte_
97 * representation of the string. If the caller wants to know
98 * where it ended, count multibyte characters to find the
99 * corresponding position in the wide char string.
100 */
101 if (endptr != NULL) {
102 *endptr = (wchar_t *)nptr + (end - buf);
103 if (buf != end)
104 *endptr += spaces;
105 }
106
107 free(buf);
108
109 return (val);
110 }
111 double
wcstod(const wchar_t * __restrict nptr,wchar_t ** __restrict endptr)112 wcstod(const wchar_t * __restrict nptr, wchar_t ** __restrict endptr)
113 {
114 return wcstod_l(nptr, endptr, __get_locale());
115 }
116