stdlib/wctomb.c

   1 /* Copyright (C) 1991, 92, 95, 96, 97, 98, 99 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  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 extern mbstate_t __no_r_state;  /* Defined in mbtowc.c.  */
  27
  28 /* Convert WCHAR into its multibyte character representation,
  29    putting this in S and returning its length.
  30
  31    Attention: this function should NEVER be intentionally used.
  32    The interface is completely stupid.  The state is shared between
  33    all conversion functions.  You should use instead the restartable
  34    version `wcrtomb'.  */
  35 int
  36 wctomb (char *s, wchar_t wchar)
  37 {
  38   /* If S is NULL the function has to return null or not null
  39      depending on the encoding having a state depending encoding or
  40      not.  */
  41   if (s == NULL)
  42     {
  43       /* Make sure we use the correct value.  */
  44       update_conversion_ptrs ();
  45
  46       /* This is an extension in the Unix standard which does not directly
  47          violate ISO C.  */
  48       memset (&__no_r_state, '\0', sizeof __no_r_state);
  49
  50       return __wcsmbs_gconv_fcts.tomb->__stateful;
  51     }
  52
  53   return __wcrtomb (s, wchar, &__no_r_state);
  54 }