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 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   mbstate_t temp_state;
  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
  52   /* A first special case is if S is NULL.  This means put PS in the
  53      initial state.  */
  54   if (s == NULL)
  55     {
  56       s = buf;
  57       wc = L'\0';
  58       temp_state = *data.__statep;
  59       data.__statep = &temp_state;
  60     }
  61
  62   /* Tell where we want to have the result.  */
  63   data.__outbuf = s;
  64   data.__outbufend = s + MB_CUR_MAX;
  65
  66   /* Make sure we use the correct function.  */
  67   update_conversion_ptrs ();
  68
  69   /* If WC is the NUL character we write into the output buffer the byte
  70      sequence necessary for PS to get into the initial state, followed
  71      by a NUL byte.  */
  72   if (wc == L'\0')
  73     {
  74       status = (*__wcsmbs_gconv_fcts.tomb->__fct) (__wcsmbs_gconv_fcts.tomb,
  75                                                    &data, NULL, NULL,
  76                                                    &dummy, 1, 1);
  77
  78       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  79         *data.__outbuf++ = '\0';
  80     }
  81   else
  82     {
  83       /* Do a normal conversion.  */
  84       const unsigned char *inbuf = (const unsigned char *) &wc;
  85
  86       status = (*__wcsmbs_gconv_fcts.tomb->__fct) (__wcsmbs_gconv_fcts.tomb,
  87                                                    &data, &inbuf,
  88                                                    inbuf + sizeof (wchar_t),
  89                                                    &dummy, 0, 1);
  90     }
  91
  92   /* There must not be any problems with the conversion but illegal input
  93      characters.  The output buffer must be large enough, otherwise the
  94      definition of MB_CUR_MAX is not correct.  All the other possible
  95      errors also must not happen.  */
  96   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
  97           || status == __GCONV_ILLEGAL_INPUT
  98           || status == __GCONV_INCOMPLETE_INPUT
  99           || status == __GCONV_FULL_OUTPUT);
 100
 101   if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 102       || status == __GCONV_FULL_OUTPUT)
 103     result = data.__outbuf - (unsigned char *) s;
 104   else
 105     {
 106       result = (size_t) -1;
 107       __set_errno (EILSEQ);
 108     }
 109
 110   return result;
 111 }
 112 weak_alias (__wcrtomb, wcrtomb)