wcsmbs/wcsrtombs.c

   1 /* Copyright (C) 1996, 1997, 1998, 1999 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Ulrich Drepper <drepper@gnu.org>, 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 <stdlib.h>
  22 #include <gconv.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 __wcsrtombs (dst, src, len, ps)
  38      char *dst;
  39      const wchar_t **src;
  40      size_t len;
  41      mbstate_t *ps;
  42 {
  43   struct __gconv_step_data data;
  44   int status;
  45   size_t result;
  46   struct __gconv_step *tomb;
  47
  48   /* Tell where we want the result.  */
  49   data.__invocation_counter = 0;
  50   data.__internal_use = 1;
  51   data.__is_last = 1;
  52   data.__statep = ps ?: &state;
  53
  54   /* Make sure we use the correct function.  */
  55   update_conversion_ptrs ();
  56
  57   /* Get the structure with the function pointers.  */
  58   tomb = __wcsmbs_gconv_fcts.tomb;
  59
  60   /* We have to handle DST == NULL special.  */
  61   if (dst == NULL)
  62     {
  63       unsigned char buf[256];           /* Just an arbitrary value.  */
  64       const wchar_t *srcend = *src + __wcslen (*src) + 1;
  65       const wchar_t *inbuf = *src;
  66       size_t dummy;
  67
  68       result = 0;
  69       data.__outbufend = buf + sizeof (buf);
  70
  71       do
  72         {
  73           data.__outbuf = buf;
  74
  75           status = (*tomb->__fct) (__wcsmbs_gconv_fcts.tomb, &data,
  76                                    (const unsigned char **) &inbuf,
  77                                    (const unsigned char *) srcend, &dummy, 0);
  78
  79           /* Count the number of bytes.  */
  80           result += data.__outbuf - buf;
  81         }
  82       while (status == __GCONV_FULL_OUTPUT);
  83
  84       if (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT)
  85         {
  86           /* There better should be a NUL byte at the end.  */
  87           assert (data.__outbuf[-1] == '\0');
  88           /* Don't count the NUL character in.  */
  89           --result;
  90         }
  91     }
  92   else
  93     {
  94       /* This code is based on the safe assumption that all internal
  95          multi-byte encodings use the NUL byte only to mark the end
  96          of the string.  */
  97       const wchar_t *srcend = *src + __wcsnlen (*src, len * MB_CUR_MAX) + 1;
  98       size_t dummy;
  99
 100       data.__outbuf = dst;
 101       data.__outbufend = dst + len;
 102
 103       status = (*tomb->__fct) (__wcsmbs_gconv_fcts.tomb, &data,
 104                                (const unsigned char **) src,
 105                                (const unsigned char *) srcend, &dummy, 0);
 106
 107       /* Count the number of bytes.  */
 108       result = data.__outbuf - (unsigned char *) dst;
 109
 110       /* We have to determine whether the last character converted
 111          is the NUL character.  */
 112       if ((status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 113            || status == __GCONV_FULL_OUTPUT)
 114           && data.__outbuf[-1] == '\0')
 115         {
 116           assert (data.__outbuf != (unsigned char *) dst);
 117           assert (__mbsinit (data.__statep));
 118           *src = NULL;
 119           --result;
 120         }
 121     }
 122
 123   /* There must not be any problems with the conversion but illegal input
 124      characters.  */
 125   assert (status == __GCONV_OK || status == __GCONV_EMPTY_INPUT
 126           || status == __GCONV_ILLEGAL_INPUT
 127           || status == __GCONV_INCOMPLETE_INPUT
 128           || status == __GCONV_FULL_OUTPUT);
 129
 130   if (status != __GCONV_OK && status != __GCONV_FULL_OUTPUT
 131       && status != __GCONV_EMPTY_INPUT)
 132     {
 133       result = (size_t) -1;
 134       __set_errno (EILSEQ);
 135     }
 136
 137   return result;
 138 }
 139 weak_alias (__wcsrtombs, wcsrtombs)