stdlib/wctomb.c

   1 /* Copyright (C) 1991, 1992, 1995-1999, 2002, 2008
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library 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 GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <wchar.h>
  22 #include <gconv.h>
  23 #include <wcsmbs/wcsmbsload.h>
  24
  25
  26 /* Shared with __wctomb_chk.  */
  27 mbstate_t __wctomb_state attribute_hidden;
  28
  29 /* Convert WCHAR into its multibyte character representation,
  30    putting this in S and returning its length.
  31
  32    Attention: this function should NEVER be intentionally used.
  33    The interface is completely stupid.  The state is shared between
  34    all conversion functions.  You should use instead the restartable
  35    version `wcrtomb'.  */
  36 int
  37 wctomb (char *s, wchar_t wchar)
  38 {
  39   /* If S is NULL the function has to return null or not null
  40      depending on the encoding having a state depending encoding or
  41      not.  */
  42   if (s == NULL)
  43     {
  44       const struct gconv_fcts *fcts;
  45
  46       /* Get the conversion functions.  */
  47       fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
  48
  49       /* This is an extension in the Unix standard which does not directly
  50          violate ISO C.  */
  51       memset (&__wctomb_state, '\0', sizeof __wctomb_state);
  52
  53       return fcts->tomb->__stateful;
  54     }
  55
  56   return __wcrtomb (s, wchar, &__wctomb_state);
  57 }
  58 libc_hidden_def (wctomb)