iconvdata/8bit-gap.c

   1 /* Generic conversion to and from 8bit charsets,
   2    converting from UCS using gaps.
   3    Copyright (C) 1997, 1998 Free Software Foundation, Inc.
   4    This file is part of the GNU C Library.
   5    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include <gconv.h>
  23 #include <inttypes.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27
  28 struct gap
  29 {
  30   uint16_t start;
  31   uint16_t end;
  32   int16_t idx;
  33 };
  34
  35 /* Now we can include the tables.  */
  36 #include TABLES
  37
  38 /* Direction of the transformation.  */
  39 enum direction
  40 {
  41   illegal,
  42   to_8bit,
  43   from_8bit
  44 };
  45
  46 struct s_8bit_data
  47 {
  48   enum direction dir;
  49 };
  50
  51
  52 int
  53 gconv_init (struct gconv_step *step, struct gconv_step_data *data)
  54 {
  55   /* Determine which direction.  */
  56   struct s_8bit_data *new_data;
  57   enum direction dir;
  58   int result;
  59
  60   if (strcasestr (step->from_name, NAME) != NULL)
  61     dir = from_8bit;
  62   else if (strcasestr (step->to_name, NAME) != NULL)
  63     dir = to_8bit;
  64   else
  65     dir = illegal;
  66
  67   result = GCONV_NOCONV;
  68   if (dir != illegal
  69       && ((new_data
  70            = (struct s_8bit_data *) malloc (sizeof (struct s_8bit_data)))
  71           != NULL))
  72     {
  73       new_data->dir = dir;
  74       data->data = new_data;
  75       result = GCONV_OK;
  76     }
  77
  78   return result;
  79 }
  80
  81
  82 void
  83 gconv_end (struct gconv_step_data *data)
  84 {
  85   free (data->data);
  86 }
  87
  88
  89 int
  90 gconv (struct gconv_step *step, struct gconv_step_data *data,
  91        const char *inbuf, size_t *inbufsize, size_t *written, int do_flush)
  92 {
  93   struct gconv_step *next_step = step + 1;
  94   struct gconv_step_data *next_data = data + 1;
  95   gconv_fct fct = next_step->fct;
  96   size_t do_write;
  97   int result;
  98
  99   /* If the function is called with no input this means we have to reset
 100      to the initial state.  The possibly partly converted input is
 101      dropped.  */
 102   if (do_flush)
 103     {
 104       do_write = 0;
 105
 106       /* Call the steps down the chain if there are any.  */
 107       if (data->is_last)
 108         result = GCONV_OK;
 109       else
 110         {
 111           struct gconv_step *next_step = step + 1;
 112           struct gconv_step_data *next_data = data + 1;
 113
 114           result = (*fct) (next_step, next_data, NULL, 0, written, 1);
 115
 116           /* Clear output buffer.  */
 117           data->outbufavail = 0;
 118         }
 119     }
 120   else
 121     {
 122       enum direction dir = ((struct s_8bit_data *) data->data)->dir;
 123
 124       do_write = 0;
 125
 126       do
 127         {
 128           result = GCONV_OK;
 129
 130           if (dir == from_8bit)
 131             {
 132               size_t inchars = *inbufsize;
 133               size_t outwchars = data->outbufavail;
 134               char *outbuf = data->outbuf;
 135               size_t cnt = 0;
 136
 137               while (cnt < inchars
 138                      && (outwchars + sizeof (wchar_t) <= data->outbufsize))
 139                 {
 140                   wchar_t ch = to_ucs4[(unsigned int) inbuf[cnt]];
 141
 142                   if (ch == L'\0' && inbuf[cnt] != '\0')
 143                     {
 144                       /* This is an illegal character.  */
 145                       result = GCONV_ILLEGAL_INPUT;
 146                       break;
 147                     }
 148
 149                   *((wchar_t *) (outbuf + outwchars)) = ch;
 150                   ++do_write;
 151                   outwchars += sizeof (wchar_t);
 152                   ++cnt;
 153                 }
 154               *inbufsize -= cnt;
 155               data->outbufavail = outwchars;
 156             }
 157           else
 158             {
 159               size_t inwchars = *inbufsize;
 160               size_t outchars = data->outbufavail;
 161               char *outbuf = data->outbuf;
 162               size_t cnt = 0;
 163
 164               while (inwchars >= cnt + sizeof (wchar_t)
 165                      && outchars < data->outbufsize)
 166                 {
 167                   const struct gap *rp = from_idx;
 168                   unsigned int ch = *((wchar_t *) (inbuf + cnt));
 169                   char res;
 170
 171                   while (ch > rp->end)
 172                     ++rp;
 173                   if (ch < rp->start)
 174                     /* No valid character.  */
 175                     break;
 176
 177                   res = from_ucs4[ch + rp->idx];
 178                   if (res == '\0' && ch != 0)
 179                     /* No valid character.  */
 180                     break;
 181
 182                   outbuf[outchars] = res;
 183                   ++do_write;
 184                   ++outchars;
 185                   cnt += sizeof (wchar_t);
 186                 }
 187               *inbufsize -= cnt;
 188               data->outbufavail = outchars;
 189
 190               if (outchars < data->outbufsize)
 191                 {
 192                   /* If there is still room in the output buffer something
 193                      is wrong with the input.  */
 194                   if (inwchars >= cnt + sizeof (wchar_t))
 195                     {
 196                       /* An error occurred.  */
 197                       result = GCONV_ILLEGAL_INPUT;
 198                       break;
 199                     }
 200                   if (inwchars != cnt)
 201                     {
 202                       /* There are some unprocessed bytes at the end of the
 203                          input buffer.  */
 204                       result = GCONV_INCOMPLETE_INPUT;
 205                       break;
 206                     }
 207                 }
 208             }
 209
 210           if (result != GCONV_OK)
 211             break;
 212
 213           if (data->is_last)
 214             {
 215               /* This is the last step.  */
 216               result = (*inbufsize > (dir == from_8bit
 217                                       ? 0 : sizeof (wchar_t) - 1)
 218                         ? GCONV_FULL_OUTPUT : GCONV_EMPTY_INPUT);
 219               break;
 220             }
 221
 222           /* Status so far.  */
 223           result = GCONV_EMPTY_INPUT;
 224
 225           if (data->outbufavail > 0)
 226             {
 227               /* Call the functions below in the chain.  */
 228               size_t newavail = data->outbufavail;
 229
 230               result = (*fct) (next_step, next_data, data->outbuf, &newavail,
 231                                written, 0);
 232
 233               /* Correct the output buffer.  */
 234               if (newavail != data->outbufavail && newavail > 0)
 235                 {
 236                   memmove (data->outbuf,
 237                            &data->outbuf[data->outbufavail - newavail],
 238                            newavail);
 239                   data->outbufavail = newavail;
 240                 }
 241             }
 242         }
 243       while (*inbufsize > 0 && result == GCONV_EMPTY_INPUT);
 244     }
 245
 246   if (written != NULL && data->is_last)
 247     *written = do_write;
 248
 249   return result;
 250 }