wcsmbs/wcrtomb.c

   1 /* Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@cygnus.com>, 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 <errno.h>
  22 #include <gconv.h>
  23 #include <stdlib.h>
  24 #include <wchar.h>
  25 #include <wcsmbsload.h>
  26
  27 #include <assert.h>
  28
  29 #ifndef EILSEQ
  30 # define EILSEQ EINVAL
  31 #endif
  32
  33
  34 /* This is the private state used if PS is NULL.  */
  35 static mbstate_t state;
  36
  37 size_t
  38 __wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
  39 {
  40   char buf[MB_CUR_MAX];
  41   struct __gconv_step_data data;
  42   int status;
  43   size_t result;
  44   size_t dummy;
  45
  46   /* Set information for this step.  */
  47   data.__invocation_counter = 0;
  48   data.__internal_use = 1;
  49   data.__flags = __GCONV_IS_LAST;
  50   data.__statep = ps ?: &state;
  51   data.__trans = NULL;
  52
  53   /* A first special case is if S is NULL.  This means put PS in the
  54      initial state.  */
  55   if (s == NULL)
  56     {
  57       s = buf;
  58       wc = L'\0';
  59     }
  60
  61   /* Tell where we want to have the result.  */
  62   data.__outbuf = s;
  63   data.__outbufend = s + MB_CUR_MAX;
  64
  65   /* Make sure we use the correct function.  */
  66   update_conversion_ptrs ();
  67
  68   /* If WC is the NUL character we write into the output buffer the byte
  69      sequence necessary for PS to get into the initial state, followed
  70      by a NUL byte.  */
  71   if (wc == L'\0')
  72     {
  73       status = DL_CALL_FCT (__wcsmbs_gconv_fcts.tomb->__fct,
  74                             (__wcsmbs_gconv_fcts.tomb, &data, NULL, NULL,
  75                              NULL, &dummy, 1, 1));
  76
  77       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  78         *data.__outbuf++ = '\0';
  79     }
  80   else
  81     {
  82       /* Do a normal conversion.  */
  83       const unsigned char *inbuf = (const unsigned char *) &wc;
  84
  85       status = DL_CALL_FCT (__wcsmbs_gconv_fcts.tomb->__fct,
  86                             (__wcsmbs_gconv_fcts.tomb, &data, &inbuf,
  87                              inbuf + sizeof (wchar_t), NULL, &dummy, 0, 1));
  88     }
  89
  90   /* There must not be any problems with the conversion but illegal input
  91      characters.  The output buffer must be large enough, otherwise the
  92      definition of MB_CUR_MAX is not correct.  All the other possible
  93      errors also must not happen.  */
  94   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
  95           || status == __GCONV_ILLEGAL_INPUT
  96           || status == __GCONV_INCOMPLETE_INPUT
  97           || status == __GCONV_FULL_OUTPUT);
  98
  99   if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 100       || status == __GCONV_FULL_OUTPUT)
 101     result = data.__outbuf - (unsigned char *) s;
 102   else
 103     {
 104       result = (size_t) -1;
 105       __set_errno (EILSEQ);
 106     }
 107
 108   return result;
 109 }
 110 weak_alias (__wcrtomb, wcrtomb)