iconvdata/iso8859-1.c

   1 /* Conversion to and from ISO 8859-1.
   2    Copyright (C) 1997 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <gconv.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 /* Direction of the transformation.  */
  26 enum direction
  27 {
  28   illegal,
  29   to_iso88591,
  30   from_iso88591
  31 };
  32
  33 struct iso88591_data
  34 {
  35   enum direction dir;
  36 };
  37
  38
  39 int
  40 gconv_init (struct gconv_step *step, struct gconv_step_data *data)
  41 {
  42   /* Determine which direction.  */
  43   struct iso88591_data *new_data;
  44   enum direction dir;
  45   int result;
  46
  47   if (__strcasestr (step->from_name, "ISO-8859-1") != NULL)
  48     dir = from_iso88591;
  49   else if (__strcasestr (step->to_name, "ISO-8859-1") != NULL)
  50     dir = to_iso88591;
  51   else
  52     dir = illegal;
  53
  54   result = GCONV_NOCONV;
  55   if (dir != illegal
  56       && ((new_data
  57            = (struct iso88591_data *) malloc (sizeof (struct iso88591_data)))
  58           != NULL))
  59     {
  60       new_data->dir = dir;
  61       data->data = new_data;
  62       result = GCONV_OK;
  63     }
  64
  65   return result;
  66 }
  67
  68
  69 void
  70 gconv_end (struct gconv_step_data *data)
  71 {
  72   free (data->data);
  73 }
  74
  75
  76 int
  77 gconv (struct gconv_step *step, struct gconv_step_data *data,
  78        const char *inbuf, size_t *inbufsize, size_t *written, int do_flush)
  79 {
  80   struct gconv_step *next_step = step + 1;
  81   struct gconv_step_data *next_data = data + 1;
  82   gconv_fct fct = next_step->fct;
  83   size_t do_write;
  84   int result;
  85
  86   /* If the function is called with no input this means we have to reset
  87      to the initial state.  The possibly partly converted input is
  88      dropped.  */
  89   if (do_flush)
  90     {
  91       do_write = 0;
  92
  93       /* Call the steps down the chain if there are any.  */
  94       if (data->is_last)
  95         result = GCONV_OK;
  96       else
  97         {
  98           struct gconv_step *next_step = step + 1;
  99           struct gconv_step_data *next_data = data + 1;
 100
 101           result = (*fct) (next_step, next_data, NULL, 0, written, 1);
 102
 103           /* Clear output buffer.  */
 104           data->outbufavail = 0;
 105         }
 106     }
 107   else
 108     {
 109       enum direction dir = ((struct iso88591_data *) data->data)->dir;
 110
 111       do_write = 0;
 112
 113       do
 114         {
 115           result = GCONV_OK;
 116
 117           if (dir == from_iso88591)
 118             {
 119               size_t inchars = *inbufsize;
 120               size_t outwchars = data->outbufavail;
 121               char *outbuf = data->outbuf;
 122               size_t cnt = 0;
 123
 124               while (cnt < inchars
 125                      && (outwchars + sizeof (wchar_t) <= data->outbufsize))
 126                 {
 127                   *((wchar_t *) (outbuf + outwchars)) = inbuf[cnt];
 128                   ++do_write;
 129                   outwchars += sizeof (wchar_t);
 130                   ++cnt;
 131                 }
 132               *inbufsize -= cnt;
 133               data->outbufavail = outwchars;
 134             }
 135           else
 136             {
 137               size_t inwchars = *inbufsize;
 138               size_t outchars = data->outbufavail;
 139               char *outbuf = data->outbuf;
 140               size_t cnt = 0;
 141
 142               while (inwchars >= cnt + sizeof (wchar_t)
 143                      && outchars < data->outbufsize)
 144                 {
 145                   if (*((wchar_t *) (inbuf + cnt)) >= L'\0'
 146                       && *((wchar_t *) (inbuf + cnt)) <= L'\377')
 147                     outbuf[outchars] = *((wchar_t *) (inbuf + cnt));
 148                   else
 149                     /* Here is where the transliteration would enter the
 150                        scene.  */
 151                     break;
 152
 153                   ++do_write;
 154                   ++outchars;
 155                   cnt += sizeof (wchar_t);
 156                 }
 157               *inbufsize -= cnt;
 158               data->outbufavail = outchars;
 159
 160               if (outchars < data->outbufsize)
 161                 {
 162                   /* If there is still room in the output buffer something
 163                      is wrong with the input.  */
 164                   if (inwchars >= cnt + sizeof (wchar_t))
 165                     {
 166                       /* An error occurred.  */
 167                       result = GCONV_ILLEGAL_INPUT;
 168                       break;
 169                     }
 170                   if (inwchars != cnt)
 171                     {
 172                       /* There are some unprocessed bytes at the end of the
 173                          input buffer.  */
 174                       result = GCONV_INCOMPLETE_INPUT;
 175                       break;
 176                     }
 177                 }
 178             }
 179
 180           if (result != GCONV_OK)
 181             break;
 182
 183           if (data->is_last)
 184             {
 185               /* This is the last step.  */
 186               result = (*inbufsize > (dir == from_iso88591
 187                                       ? 0 : sizeof (wchar_t) - 1)
 188                         ? GCONV_FULL_OUTPUT : GCONV_EMPTY_INPUT);
 189               break;
 190             }
 191
 192           /* Status so far.  */
 193           result = GCONV_EMPTY_INPUT;
 194
 195           if (data->outbufavail > 0)
 196             {
 197               /* Call the functions below in the chain.  */
 198               size_t newavail = data->outbufavail;
 199
 200               result = (*fct) (next_step, next_data, data->outbuf, &newavail,
 201                                written, 0);
 202
 203               /* Correct the output buffer.  */
 204               if (newavail != data->outbufavail && newavail > 0)
 205                 {
 206                   memmove (data->outbuf,
 207                            &data->outbuf[data->outbufavail - newavail],
 208                            newavail);
 209                   data->outbufavail = newavail;
 210                 }
 211             }
 212         }
 213       while (*inbufsize > 0 && result == GCONV_EMPTY_INPUT);
 214     }
 215
 216   if (written != NULL && data->is_last)
 217     *written = do_write;
 218
 219   return result;
 220 }