1  /* Convert wide character to multibyte character.
       2     Copyright (C) 2008-2023 Free Software Foundation, Inc.
       3     Written by Bruno Haible <bruno@clisp.org>, 2008.
       4  
       5     This file is free software: you can redistribute it and/or modify
       6     it under the terms of the GNU Lesser General Public License as
       7     published by the Free Software Foundation; either version 2.1 of the
       8     License, or (at your option) any later version.
       9  
      10     This file 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 Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser 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  #undef wcrtomb
      30  {
      31    /* This implementation of wcrtomb supports only stateless encodings.
      32       ps must be in the initial state.  */
      33    if (ps != NULL && !mbsinit (ps))
      34      {
      35        errno = EINVAL;
      36        return (size_t)(-1);
      37      }
      38  
      39  #if !HAVE_WCRTOMB                       /* IRIX 6.5 */ \
      40      || WCRTOMB_RETVAL_BUG               /* Solaris 11.3, MSVC */ \
      41      || WCRTOMB_C_LOCALE_BUG             /* Android */
      42    if (s == NULL)
      43      /* We know the NUL wide character corresponds to the NUL character.  */
      44      return 1;
      45    else
      46  #endif
      47      {
      48  #if HAVE_WCRTOMB
      49  # if WCRTOMB_C_LOCALE_BUG               /* Android */
      50        /* Implement consistently with mbrtowc(): through a 1:1 correspondence,
      51           as in ISO-8859-1.  */
      52        if (wc >= 0 && wc <= 0xff)
      53          {
      54            *s = (unsigned char) wc;
      55            return 1;
      56          }
      57        else
      58          {
      59            errno = EILSEQ;
      60            return (size_t)(-1);
      61          }
      62  # else
      63        return wcrtomb (s, wc, ps);
      64  # endif
      65  #else                                   /* IRIX 6.5 */
      66        /* Fallback for platforms that don't have wcrtomb().
      67           Implement on top of wctomb().
      68           This code is not multithread-safe.  */
      69        int ret = wctomb (s, wc);
      70  
      71        if (ret >= 0)
      72          return ret;
      73        else
      74          {
      75            errno = EILSEQ;
      76            return (size_t)(-1);
      77          }
      78  #endif
      79      }
      80  }