xref: /freebsd/lib/libc/locale/wcstof.c (revision 9336e0699bda8a301cd2bfa37106b6ec5e32012e)
1 /*-
2  * Copyright (c) 2002, 2003 Tim J. Robbins
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #include <sys/cdefs.h>
28 __FBSDID("$FreeBSD$");
29 
30 #include <stdlib.h>
31 #include <wchar.h>
32 #include <wctype.h>
33 
34 /*
35  * See wcstod() for comments as to the logic used.
36  */
37 float
38 wcstof(const wchar_t * __restrict nptr, wchar_t ** __restrict endptr)
39 {
40 	static const mbstate_t initial;
41 	mbstate_t mbs;
42 	float val;
43 	char *buf, *end;
44 	const wchar_t *wcp;
45 	size_t len;
46 
47 	while (iswspace(*nptr))
48 		nptr++;
49 
50 	wcp = nptr;
51 	mbs = initial;
52 	if ((len = wcsrtombs(NULL, &wcp, 0, &mbs)) == (size_t)-1) {
53 		if (endptr != NULL)
54 			*endptr = (wchar_t *)nptr;
55 		return (0.0);
56 	}
57 	if ((buf = malloc(len + 1)) == NULL)
58 		return (0.0);
59 	mbs = initial;
60 	wcsrtombs(buf, &wcp, len + 1, &mbs);
61 
62 	val = strtof(buf, &end);
63 
64 	if (endptr != NULL)
65 		*endptr = (wchar_t *)nptr + (end - buf);
66 
67 	free(buf);
68 
69 	return (val);
70 }
71