iconv/gconv_open.c

   1 /* Find matching transformation algorithms and initialize steps.
   2    Copyright (C) 1997,1998,1999,2000,2001,2004,2005
   3         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 Lesser General Public
   9    License as published by the Free Software Foundation; either
  10    version 2.1 of the 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    Lesser General Public License for more details.
  16
  17    You should have received a copy of the GNU Lesser General Public
  18    License along with the GNU C Library; if not, write to the Free
  19    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  20    02111-1307 USA.  */
  21
  22 #include <errno.h>
  23 #include <locale.h>
  24 #include "../locale/localeinfo.h"
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include <gconv_int.h>
  29
  30
  31 int
  32 internal_function
  33 __gconv_open (const char *toset, const char *fromset, __gconv_t *handle,
  34               int flags)
  35 {
  36   struct __gconv_step *steps;
  37   size_t nsteps;
  38   __gconv_t result = NULL;
  39   size_t cnt = 0;
  40   int res;
  41   int conv_flags = 0;
  42   const char *errhand;
  43   const char *ignore;
  44   struct trans_struct *trans = NULL;
  45
  46   /* Find out whether any error handling method is specified.  */
  47   errhand = strchr (toset, '/');
  48   if (errhand != NULL)
  49     errhand = strchr (errhand + 1, '/');
  50   if (__builtin_expect (errhand != NULL, 1))
  51     {
  52       if (*++errhand == '\0')
  53         errhand = NULL;
  54       else
  55         {
  56           /* Make copy without the error handling description.  */
  57           char *newtoset = (char *) alloca (errhand - toset + 1);
  58           char *tok;
  59           char *ptr;
  60
  61           newtoset[errhand - toset] = '\0';
  62           toset = memcpy (newtoset, toset, errhand - toset);
  63
  64           /* Find the appropriate transliteration handlers.  */
  65           tok = strdupa (errhand);
  66
  67           tok = __strtok_r (tok, ",", &ptr);
  68           while (tok != NULL)
  69             {
  70               if (__strcasecmp_l (tok, "TRANSLIT", &_nl_C_locobj) == 0)
  71                 {
  72                   /* It's the builtin transliteration handling.  We only
  73                      support it for working on the internal encoding.  */
  74                   static const char *internal_trans_names[1] = { "INTERNAL" };
  75                   struct trans_struct *lastp = NULL;
  76                   struct trans_struct *runp;
  77
  78                   for (runp = trans; runp != NULL; runp = runp->next)
  79                     if (runp->trans_fct == __gconv_transliterate)
  80                       break;
  81                     else
  82                       lastp = runp;
  83
  84                   if (runp == NULL)
  85                     {
  86                       struct trans_struct *newp;
  87
  88                       newp = (struct trans_struct *) alloca (sizeof (*newp));
  89                       memset (newp, '\0', sizeof (*newp));
  90
  91                       /* We leave the `name' field zero to signal that
  92                          this is an internal transliteration step.  */
  93                       newp->csnames = internal_trans_names;
  94                       newp->ncsnames = 1;
  95                       newp->trans_fct = __gconv_transliterate;
  96
  97                       if (lastp == NULL)
  98                         trans = newp;
  99                       else
 100                         lastp->next = newp;
 101                     }
 102                 }
 103               else if (__strcasecmp_l (tok, "IGNORE", &_nl_C_locobj) == 0)
 104                 /* Set the flag to ignore all errors.  */
 105                 conv_flags |= __GCONV_IGNORE_ERRORS;
 106               else
 107                 {
 108                   /* `tok' is possibly a module name.  We'll see later
 109                      whether we can find it.  But first see that we do
 110                      not already a module of this name.  */
 111                   struct trans_struct *lastp = NULL;
 112                   struct trans_struct *runp;
 113
 114                   for (runp = trans; runp != NULL; runp = runp->next)
 115                     if (runp->name != NULL
 116                         && __strcasecmp_l (tok, runp->name,
 117                                            &_nl_C_locobj) == 0)
 118                       break;
 119                     else
 120                       lastp = runp;
 121
 122                   if (runp == NULL)
 123                     {
 124                       struct trans_struct *newp;
 125
 126                       newp = (struct trans_struct *) alloca (sizeof (*newp));
 127                       memset (newp, '\0', sizeof (*newp));
 128                       newp->name = tok;
 129
 130                       if (lastp == NULL)
 131                         trans = newp;
 132                       else
 133                         lastp->next = newp;
 134                     }
 135                 }
 136
 137               tok = __strtok_r (NULL, ",", &ptr);
 138             }
 139         }
 140     }
 141
 142   /* For the source character set we ignore the error handler specification.
 143      XXX Is this really always the best?  */
 144   ignore = strchr (fromset, '/');
 145   if (ignore != NULL && (ignore = strchr (ignore + 1, '/')) != NULL
 146       && *++ignore != '\0')
 147     {
 148       char *newfromset = (char *) alloca (ignore - fromset + 1);
 149
 150       newfromset[ignore - fromset] = '\0';
 151       fromset = memcpy (newfromset, fromset, ignore - fromset);
 152     }
 153
 154   /* If the string is empty define this to mean the charset of the
 155      currently selected locale.  */
 156   if (strcmp (toset, "//") == 0)
 157     {
 158       const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
 159       size_t len = strlen (codeset);
 160       char *dest;
 161       toset = dest = (char *) alloca (len + 3);
 162       memcpy (__mempcpy (dest, codeset, len), "//", 3);
 163     }
 164   if (strcmp (fromset, "//") == 0)
 165     {
 166       const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
 167       size_t len = strlen (codeset);
 168       char *dest;
 169       fromset = dest = (char *) alloca (len + 3);
 170       memcpy (__mempcpy (dest, codeset, len), "//", 3);
 171     }
 172
 173   res = __gconv_find_transform (toset, fromset, &steps, &nsteps, flags);
 174   if (res == __GCONV_OK)
 175     {
 176       /* Find the modules.  */
 177       struct trans_struct *lastp = NULL;
 178       struct trans_struct *runp;
 179
 180       for (runp = trans; runp != NULL; runp = runp->next)
 181         {
 182           if (runp->name == NULL
 183               || __builtin_expect (__gconv_translit_find (runp), 0) == 0)
 184             lastp = runp;
 185           else
 186             {
 187               /* This means we haven't found the module.  Remove it.  */
 188               if (lastp == NULL)
 189                 trans  = runp->next;
 190               else
 191                 lastp->next  = runp->next;
 192             }
 193         }
 194
 195       /* Allocate room for handle.  */
 196       result = (__gconv_t) malloc (sizeof (struct __gconv_info)
 197                                    + (nsteps
 198                                       * sizeof (struct __gconv_step_data)));
 199       if (result == NULL)
 200         res = __GCONV_NOMEM;
 201       else
 202         {
 203           size_t n;
 204
 205           /* Remember the list of steps.  */
 206           result->__steps = steps;
 207           result->__nsteps = nsteps;
 208
 209           /* Clear the array for the step data.  */
 210           memset (result->__data, '\0',
 211                   nsteps * sizeof (struct __gconv_step_data));
 212
 213           /* Call all initialization functions for the transformation
 214              step implementations.  */
 215           for (cnt = 0; cnt < nsteps; ++cnt)
 216             {
 217               size_t size;
 218
 219               /* Would have to be done if we would not clear the whole
 220                  array above.  */
 221 #if 0
 222               /* Reset the counter.  */
 223               result->__data[cnt].__invocation_counter = 0;
 224
 225               /* It's a regular use.  */
 226               result->__data[cnt].__internal_use = 0;
 227 #endif
 228
 229               /* We use the `mbstate_t' member in DATA.  */
 230               result->__data[cnt].__statep = &result->__data[cnt].__state;
 231
 232               /* Now see whether we can use any of the transliteration
 233                  modules for this step.  */
 234               for (runp = trans; runp != NULL; runp = runp->next)
 235                 for (n = 0; n < runp->ncsnames; ++n)
 236                   if (__strcasecmp_l (steps[cnt].__from_name,
 237                                       runp->csnames[n], &_nl_C_locobj) == 0)
 238                     {
 239                       void *data = NULL;
 240
 241                       /* Match!  Now try the initializer.  */
 242                       if (runp->trans_init_fct == NULL
 243                           || (runp->trans_init_fct (&data,
 244                                                     steps[cnt].__to_name)
 245                               == __GCONV_OK))
 246                         {
 247                           /* Append at the end of the list.  */
 248                           struct __gconv_trans_data *newp;
 249                           struct __gconv_trans_data **lastp;
 250
 251                           newp = (struct __gconv_trans_data *)
 252                             malloc (sizeof (struct __gconv_trans_data));
 253                           if (newp == NULL)
 254                             {
 255                               res = __GCONV_NOMEM;
 256                               goto bail;
 257                             }
 258
 259                           newp->__trans_fct = runp->trans_fct;
 260                           newp->__trans_context_fct = runp->trans_context_fct;
 261                           newp->__trans_end_fct = runp->trans_end_fct;
 262                           newp->__data = data;
 263                           newp->__next = NULL;
 264
 265                           lastp = &result->__data[cnt].__trans;
 266                           while (*lastp != NULL)
 267                             lastp = &(*lastp)->__next;
 268
 269                           *lastp = newp;
 270                         }
 271                       break;
 272                     }
 273
 274               /* If this is the last step we must not allocate an
 275                  output buffer.  */
 276               if (cnt < nsteps - 1)
 277                 {
 278                   result->__data[cnt].__flags = conv_flags;
 279
 280                   /* Allocate the buffer.  */
 281                   size = (GCONV_NCHAR_GOAL * steps[cnt].__max_needed_to);
 282
 283                   result->__data[cnt].__outbuf = malloc (size);
 284                   if (result->__data[cnt].__outbuf == NULL)
 285                     {
 286                       res = __GCONV_NOMEM;
 287                       goto bail;
 288                     }
 289
 290                   result->__data[cnt].__outbufend =
 291                     result->__data[cnt].__outbuf + size;
 292                 }
 293               else
 294                 {
 295                   /* Handle the last entry.  */
 296                   result->__data[cnt].__flags = conv_flags | __GCONV_IS_LAST;
 297
 298                   break;
 299                 }
 300             }
 301         }
 302
 303       if (res != __GCONV_OK)
 304         {
 305           /* Something went wrong.  Free all the resources.  */
 306           int serrno;
 307         bail:
 308           serrno = errno;
 309
 310           if (result != NULL)
 311             {
 312               while (cnt-- > 0)
 313                 {
 314                   struct __gconv_trans_data *transp;
 315
 316                   transp = result->__data[cnt].__trans;
 317                   while (transp != NULL)
 318                     {
 319                       struct __gconv_trans_data *curp = transp;
 320                       transp = transp->__next;
 321
 322                       if (__builtin_expect (curp->__trans_end_fct != NULL, 0))
 323                         curp->__trans_end_fct (curp->__data);
 324
 325                       free (curp);
 326                     }
 327
 328                   free (result->__data[cnt].__outbuf);
 329                 }
 330
 331               free (result);
 332               result = NULL;
 333             }
 334
 335           __gconv_close_transform (steps, nsteps);
 336
 337           __set_errno (serrno);
 338         }
 339     }
 340
 341   *handle = result;
 342   return res;
 343 }