wcsmbs/wcrtomb.c

   1 /* Copyright (C) 1996,1997,1998,2000,2002 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   const struct gconv_fcts *fcts;
  46
  47   /* Set information for this step.  */
  48   data.__invocation_counter = 0;
  49   data.__internal_use = 1;
  50   data.__flags = __GCONV_IS_LAST;
  51   data.__statep = ps ?: &state;
  52   data.__trans = NULL;
  53
  54   /* A first special case is if S is NULL.  This means put PS in the
  55      initial state.  */
  56   if (s == NULL)
  57     {
  58       s = buf;
  59       wc = L'\0';
  60     }
  61
  62   /* Tell where we want to have the result.  */
  63   data.__outbuf = s;
  64   data.__outbufend = s + MB_CUR_MAX;
  65
  66   /* Get the conversion functions.  */
  67   fcts = get_gconv_fcts (_NL_CURRENT_DATA (LC_CTYPE));
  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 = DL_CALL_FCT (fcts->tomb->__fct,
  75                             (fcts->tomb, &data, NULL, NULL,
  76                              NULL, &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 = DL_CALL_FCT (fcts->tomb->__fct,
  87                             (fcts->tomb, &data, &inbuf,
  88                              inbuf + sizeof (wchar_t), NULL, &dummy, 0, 1));
  89     }
  90
  91   /* There must not be any problems with the conversion but illegal input
  92      characters.  The output buffer must be large enough, otherwise the
  93      definition of MB_CUR_MAX is not correct.  All the other possible
  94      errors also must not happen.  */
  95   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
  96           || status == __GCONV_ILLEGAL_INPUT
  97           || status == __GCONV_INCOMPLETE_INPUT
  98           || status == __GCONV_FULL_OUTPUT);
  99
 100   if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 101       || status == __GCONV_FULL_OUTPUT)
 102     result = data.__outbuf - (unsigned char *) s;
 103   else
 104     {
 105       result = (size_t) -1;
 106       __set_errno (EILSEQ);
 107     }
 108
 109   return result;
 110 }
 111 weak_alias (__wcrtomb, wcrtomb)
 112 libc_hidden_weak (wcrtomb)