wcsmbs/wctob.c

   1 /* Copyright (C) 1996-2000, 2002, 2003 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>, 1996.
   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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <dlfcn.h>
  21 #include <gconv.h>
  22 #include <stdio.h>
  23 #include <string.h>
  24 #include <wchar.h>
  25 #include <wcsmbsload.h>
  26
  27
  28 int
  29 wctob (c)
  30      wint_t c;
  31 {
  32   char buf[MB_LEN_MAX];
  33   struct __gconv_step_data data;
  34   wchar_t inbuf[1];
  35   wchar_t *inptr = inbuf;
  36   size_t dummy;
  37   int status;
  38   const struct gconv_fcts *fcts;
  39
  40   if (c == WEOF)
  41     return EOF;
  42
  43   /* Tell where we want the result.  */
  44   data.__outbuf = buf;
  45   data.__outbufend = buf + MB_LEN_MAX;
  46   data.__invocation_counter = 0;
  47   data.__internal_use = 1;
  48   data.__flags = __GCONV_IS_LAST;
  49   data.__statep = &data.__state;
  50   data.__trans = NULL;
  51
  52   /* Make sure we start in the initial state.  */
  53   memset (&data.__state, '\0', sizeof (mbstate_t));
  54
  55   /* Get the conversion functions.  */
  56   fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
  57
  58   /* Create the input string.  */
  59   inbuf[0] = c;
  60
  61   const unsigned char *argptr = (const unsigned char *) inptr;
  62   status = DL_CALL_FCT (fcts->tomb->__fct,
  63                         (fcts->tomb, &data, &argptr,
  64                          argptr + sizeof (inbuf[0]), NULL, &dummy, 0, 1));
  65
  66   /* The conversion failed or the output is too long.  */
  67   if ((status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
  68        && status != __GCONV_EMPTY_INPUT)
  69       || data.__outbuf != (unsigned char *) (buf + 1))
  70     return EOF;
  71
  72   return (unsigned char) buf[0];
  73 }