locale/FreeBSD/wcstold.c

   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: src/lib/libc/locale/wcstold.c,v 1.1 2003/03/13 06:29:53 tjr Exp $");
  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 long double
  38 wcstold(const wchar_t * __restrict nptr, wchar_t ** __restrict endptr)
  39 {
  40         static const mbstate_t initial;
  41         mbstate_t state;
  42         long double val;
  43         char *buf, *end, *p;
  44         const wchar_t *wcp;
  45         size_t clen, len;
  46
  47         while (iswspace(*nptr))
  48                 nptr++;
  49
  50         state = initial;
  51         wcp = nptr;
  52         if ((len = wcsrtombs(NULL, &wcp, 0, &state)) == (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         state = initial;
  60         wcsrtombs(buf, &wcp, len + 1, &state);
  61
  62         val = strtold(buf, &end);
  63
  64         if (endptr != NULL) {
  65 #if 1                                   /* Fast, assume 1:1 WC:MBS mapping. */
  66                 *endptr = (wchar_t *)nptr + (end - buf);
  67                 (void)clen;
  68                 (void)p;
  69 #else                                   /* Slow, conservative approach. */
  70                 state = initial;
  71                 *endptr = (wchar_t *)nptr;
  72                 p = buf;
  73                 while (p < end &&
  74                     (clen = mbrlen(p, end - p, &state)) > 0) {
  75                         p += clen;
  76                         (*endptr)++;
  77                 }
  78 #endif
  79         }
  80
  81         free(buf);
  82
  83         return (val);
  84 }