lib/wcrtomb.c

   1 /* Convert wide character to multibyte character.
   2    Copyright (C) 2008-2019 Free Software Foundation, Inc.
   3    Written by Bruno Haible <bruno@clisp.org>, 2008.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19
  20 /* Specification.  */
  21 #include <wchar.h>
  22
  23 #include <errno.h>
  24 #include <stdlib.h>
  25
  26
  27 size_t
  28 wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
  29 {
  30   /* This implementation of wcrtomb supports only stateless encodings.
  31      ps must be in the initial state.  */
  32   if (ps != NULL && !mbsinit (ps))
  33     {
  34       errno = EINVAL;
  35       return (size_t)(-1);
  36     }
  37
  38   if (s == NULL)
  39     /* We know the NUL wide character corresponds to the NUL character.  */
  40     return 1;
  41   else
  42     {
  43 #if defined __ANDROID__
  44       /* Implement consistently with mbrtowc(): through a 1:1 correspondence,
  45          as in ISO-8859-1.  */
  46       if (wc >= 0 && wc <= 0xff)
  47         {
  48           *s = (unsigned char) wc;
  49           return 1;
  50         }
  51 #else
  52       /* Implement on top of wctomb().  */
  53       int ret = wctomb (s, wc);
  54
  55       if (ret >= 0)
  56         return ret;
  57 #endif
  58       else
  59         {
  60           errno = EILSEQ;
  61           return (size_t)(-1);
  62         }
  63     }
  64 }