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_ptr) == 0)
  71                 {
  72                   /* It's the builtin transliteration handling.  We only
  73                      support it for working on the internal encoding.  */
  74                   static const char *const internal_trans_names[1]
  75                     = { "INTERNAL" };
  76                   struct trans_struct *lastp = NULL;
  77                   struct trans_struct *runp;
  78
  79                   for (runp = trans; runp != NULL; runp = runp->next)
  80                     if (runp->trans_fct == __gconv_transliterate)
  81                       break;
  82                     else
  83                       lastp = runp;
  84
  85                   if (runp == NULL)
  86                     {
  87                       struct trans_struct *newp;
  88
  89                       newp = (struct trans_struct *) alloca (sizeof (*newp));
  90                       memset (newp, '\0', sizeof (*newp));
  91
  92                       /* We leave the `name' field zero to signal that
  93                          this is an internal transliteration step.  */
  94                       newp->csnames = (const char **) internal_trans_names;
  95                       newp->ncsnames = 1;
  96                       newp->trans_fct = __gconv_transliterate;
  97
  98                       if (lastp == NULL)
  99                         trans = newp;
 100                       else
 101                         lastp->next = newp;
 102                     }
 103                 }
 104               else if (__strcasecmp_l (tok, "IGNORE", _nl_C_locobj_ptr) == 0)
 105                 /* Set the flag to ignore all errors.  */
 106                 conv_flags |= __GCONV_IGNORE_ERRORS;
 107               else
 108                 {
 109                   /* `tok' is possibly a module name.  We'll see later
 110                      whether we can find it.  But first see that we do
 111                      not already a module of this name.  */
 112                   struct trans_struct *lastp = NULL;
 113                   struct trans_struct *runp;
 114
 115                   for (runp = trans; runp != NULL; runp = runp->next)
 116                     if (runp->name != NULL
 117                         && __strcasecmp_l (tok, runp->name,
 118                                            _nl_C_locobj_ptr) == 0)
 119                       break;
 120                     else
 121                       lastp = runp;
 122
 123                   if (runp == NULL)
 124                     {
 125                       struct trans_struct *newp;
 126
 127                       newp = (struct trans_struct *) alloca (sizeof (*newp));
 128                       memset (newp, '\0', sizeof (*newp));
 129                       newp->name = tok;
 130
 131                       if (lastp == NULL)
 132                         trans = newp;
 133                       else
 134                         lastp->next = newp;
 135                     }
 136                 }
 137
 138               tok = __strtok_r (NULL, ",", &ptr);
 139             }
 140         }
 141     }
 142
 143   /* For the source character set we ignore the error handler specification.
 144      XXX Is this really always the best?  */
 145   ignore = strchr (fromset, '/');
 146   if (ignore != NULL && (ignore = strchr (ignore + 1, '/')) != NULL
 147       && *++ignore != '\0')
 148     {
 149       char *newfromset = (char *) alloca (ignore - fromset + 1);
 150
 151       newfromset[ignore - fromset] = '\0';
 152       fromset = memcpy (newfromset, fromset, ignore - fromset);
 153     }
 154
 155   /* If the string is empty define this to mean the charset of the
 156      currently selected locale.  */
 157   if (strcmp (toset, "//") == 0)
 158     {
 159       const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
 160       size_t len = strlen (codeset);
 161       char *dest;
 162       toset = dest = (char *) alloca (len + 3);
 163       memcpy (__mempcpy (dest, codeset, len), "//", 3);
 164     }
 165   if (strcmp (fromset, "//") == 0)
 166     {
 167       const char *codeset = _NL_CURRENT (LC_CTYPE, CODESET);
 168       size_t len = strlen (codeset);
 169       char *dest;
 170       fromset = dest = (char *) alloca (len + 3);
 171       memcpy (__mempcpy (dest, codeset, len), "//", 3);
 172     }
 173
 174   res = __gconv_find_transform (toset, fromset, &steps, &nsteps, flags);
 175   if (res == __GCONV_OK)
 176     {
 177       /* Find the modules.  */
 178       struct trans_struct *lastp = NULL;
 179       struct trans_struct *runp;
 180
 181       for (runp = trans; runp != NULL; runp = runp->next)
 182         {
 183           if (runp->name == NULL
 184               || __builtin_expect (__gconv_translit_find (runp), 0) == 0)
 185             lastp = runp;
 186           else
 187             {
 188               /* This means we haven't found the module.  Remove it.  */
 189               if (lastp == NULL)
 190                 trans  = runp->next;
 191               else
 192                 lastp->next  = runp->next;
 193             }
 194         }
 195
 196       /* Allocate room for handle.  */
 197       result = (__gconv_t) malloc (sizeof (struct __gconv_info)
 198                                    + (nsteps
 199                                       * sizeof (struct __gconv_step_data)));
 200       if (result == NULL)
 201         res = __GCONV_NOMEM;
 202       else
 203         {
 204           size_t n;
 205
 206           /* Remember the list of steps.  */
 207           result->__steps = steps;
 208           result->__nsteps = nsteps;
 209
 210           /* Clear the array for the step data.  */
 211           memset (result->__data, '\0',
 212                   nsteps * sizeof (struct __gconv_step_data));
 213
 214           /* Call all initialization functions for the transformation
 215              step implementations.  */
 216           for (cnt = 0; cnt < nsteps; ++cnt)
 217             {
 218               size_t size;
 219
 220               /* Would have to be done if we would not clear the whole
 221                  array above.  */
 222 #if 0
 223               /* Reset the counter.  */
 224               result->__data[cnt].__invocation_counter = 0;
 225
 226               /* It's a regular use.  */
 227               result->__data[cnt].__internal_use = 0;
 228 #endif
 229
 230               /* We use the `mbstate_t' member in DATA.  */
 231               result->__data[cnt].__statep = &result->__data[cnt].__state;
 232
 233               /* Now see whether we can use any of the transliteration
 234                  modules for this step.  */
 235               for (runp = trans; runp != NULL; runp = runp->next)
 236                 for (n = 0; n < runp->ncsnames; ++n)
 237                   if (__strcasecmp_l (steps[cnt].__from_name,
 238                                       runp->csnames[n], _nl_C_locobj_ptr) == 0)
 239                     {
 240                       void *data = NULL;
 241
 242                       /* Match!  Now try the initializer.  */
 243                       if (runp->trans_init_fct == NULL
 244                           || (runp->trans_init_fct (&data,
 245                                                     steps[cnt].__to_name)
 246                               == __GCONV_OK))
 247                         {
 248                           /* Append at the end of the list.  */
 249                           struct __gconv_trans_data *newp;
 250                           struct __gconv_trans_data **lastp;
 251
 252                           newp = (struct __gconv_trans_data *)
 253                             malloc (sizeof (struct __gconv_trans_data));
 254                           if (newp == NULL)
 255                             {
 256                               res = __GCONV_NOMEM;
 257                               goto bail;
 258                             }
 259
 260                           newp->__trans_fct = runp->trans_fct;
 261                           newp->__trans_context_fct = runp->trans_context_fct;
 262                           newp->__trans_end_fct = runp->trans_end_fct;
 263                           newp->__data = data;
 264                           newp->__next = NULL;
 265
 266                           lastp = &result->__data[cnt].__trans;
 267                           while (*lastp != NULL)
 268                             lastp = &(*lastp)->__next;
 269
 270                           *lastp = newp;
 271                         }
 272                       break;
 273                     }
 274
 275               /* If this is the last step we must not allocate an
 276                  output buffer.  */
 277               if (cnt < nsteps - 1)
 278                 {
 279                   result->__data[cnt].__flags = conv_flags;
 280
 281                   /* Allocate the buffer.  */
 282                   size = (GCONV_NCHAR_GOAL * steps[cnt].__max_needed_to);
 283
 284                   result->__data[cnt].__outbuf = malloc (size);
 285                   if (result->__data[cnt].__outbuf == NULL)
 286                     {
 287                       res = __GCONV_NOMEM;
 288                       goto bail;
 289                     }
 290
 291                   result->__data[cnt].__outbufend =
 292                     result->__data[cnt].__outbuf + size;
 293                 }
 294               else
 295                 {
 296                   /* Handle the last entry.  */
 297                   result->__data[cnt].__flags = conv_flags | __GCONV_IS_LAST;
 298
 299                   break;
 300                 }
 301             }
 302         }
 303
 304       if (res != __GCONV_OK)
 305         {
 306           /* Something went wrong.  Free all the resources.  */
 307           int serrno;
 308         bail:
 309           serrno = errno;
 310
 311           if (result != NULL)
 312             {
 313               while (cnt-- > 0)
 314                 {
 315                   struct __gconv_trans_data *transp;
 316
 317                   transp = result->__data[cnt].__trans;
 318                   while (transp != NULL)
 319                     {
 320                       struct __gconv_trans_data *curp = transp;
 321                       transp = transp->__next;
 322
 323                       if (__builtin_expect (curp->__trans_end_fct != NULL, 0))
 324                         curp->__trans_end_fct (curp->__data);
 325
 326                       free (curp);
 327                     }
 328
 329                   free (result->__data[cnt].__outbuf);
 330                 }
 331
 332               free (result);
 333               result = NULL;
 334             }
 335
 336           __gconv_close_transform (steps, nsteps);
 337
 338           __set_errno (serrno);
 339         }
 340     }
 341
 342   *handle = result;
 343   return res;
 344 }