wcsmbs/wcrtomb.c

   1 /* Copyright (C) 1996, 1997, 1998 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 Library General Public License as
   7    published by the Free Software Foundation; either version 2 of the
   8    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    Library General Public License for more details.
  14
  15    You should have received a copy of the GNU Library General Public
  16    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  17    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  18    Boston, MA 02111-1307, USA.  */
  19
  20 #include <errno.h>
  21 #include <gconv.h>
  22 #include <stdlib.h>
  23 #include <wchar.h>
  24 #include <wcsmbsload.h>
  25
  26 #include <assert.h>
  27
  28 #ifndef EILSEQ
  29 # define EILSEQ EINVAL
  30 #endif
  31
  32
  33 /* This is the private state used if PS is NULL.  */
  34 static mbstate_t state;
  35
  36 size_t
  37 __wcrtomb (char *s, wchar_t wc, mbstate_t *ps)
  38 {
  39   char buf[MB_CUR_MAX];
  40   struct gconv_step_data data;
  41   int status;
  42   size_t result;
  43   size_t dummy;
  44
  45   /* Tell where we want the result.  */
  46   data.outbuf = s;
  47   data.outbufend = s + MB_CUR_MAX;
  48   data.invocation_counter = 0;
  49   data.internal_use = 1;
  50   data.is_last = 1;
  51   data.statep = ps ?: &state;
  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       data.outbuf = buf;
  58       wc = L'\0';
  59     }
  60
  61   /* Make sure we use the correct function.  */
  62   update_conversion_ptrs ();
  63
  64   /* If WC is the NUL character we write into the output buffer the byte
  65      sequence necessary for PS to get into the initial state, followed
  66      by a NUL byte.  */
  67   if (wc == L'\0')
  68     {
  69       status = (*__wcsmbs_gconv_fcts.tomb->fct) (__wcsmbs_gconv_fcts.tomb,
  70                                                  &data, NULL, NULL, &dummy, 1);
  71
  72       if (status == GCONV_OK || status == GCONV_EMPTY_INPUT)
  73         *data.outbuf++ = '\0';
  74     }
  75   else
  76     {
  77       /* Do a normal conversion.  */
  78       const char *inbuf = (const char *) &wc;
  79
  80       status = (*__wcsmbs_gconv_fcts.tomb->fct) (__wcsmbs_gconv_fcts.tomb,
  81                                                  &data, &inbuf,
  82                                                  inbuf + sizeof (wchar_t),
  83                                                  &dummy, 0);
  84     }
  85
  86   /* There must not be any problems with the conversion but illegal input
  87      characters.  The output buffer must be large enough, otherwise the
  88      definition of MB_CUR_MAX is not correct.  All the other possible
  89      errors also must not happen.  */
  90   assert (status == GCONV_OK || status == GCONV_EMPTY_INPUT
  91           || status == GCONV_ILLEGAL_INPUT
  92           || status == GCONV_INCOMPLETE_INPUT
  93           || status == GCONV_FULL_OUTPUT);
  94
  95   if (status == GCONV_OK || status == GCONV_EMPTY_INPUT
  96       || status == GCONV_FULL_OUTPUT)
  97     result = data.outbuf - s;
  98   else
  99     {
 100       result = (size_t) -1;
 101       __set_errno (EILSEQ);
 102     }
 103
 104   return result;
 105 }
 106 weak_alias (__wcrtomb, wcrtomb)