intl/dcgettext.c

   1 /* dcgettext.c -- implemenatation of the dcgettext(3) function
   2    Copyright (C) 1995 Free Software Foundation, Inc.
   3
   4 This program is free software; you can redistribute it and/or modify
   5 it under the terms of the GNU General Public License as published by
   6 the Free Software Foundation; either version 2, or (at your option)
   7 any later version.
   8
   9 This program is distributed in the hope that it will be useful,
  10 but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 GNU General Public License for more details.
  13
  14 You should have received a copy of the GNU General Public License
  15 along with this program; if not, write to the Free Software
  16 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
  17
  18 #ifdef HAVE_CONFIG_H
  19 # include <config.h>
  20 #endif
  21
  22 #include <sys/types.h>
  23
  24 #ifdef __GNUC__
  25 # define alloca __builtin_alloca
  26 #else
  27 # if defined HAVE_ALLOCA_H || defined _LIBC
  28 #  include <alloca.h>
  29 # else
  30 #  ifdef _AIX
  31  #pragma alloca
  32 #  else
  33 #   ifndef alloca
  34 char *alloca ();
  35 #   endif
  36 #  endif
  37 # endif
  38 #endif
  39
  40 #include <errno.h>
  41 #ifndef errno
  42 extern int errno;
  43 #endif
  44
  45 #if defined STDC_HEADERS || defined _LIBC
  46 # include <stdlib.h>
  47 #else
  48 char *getenv ();
  49 # ifdef HAVE_MALLOC_H
  50 #  include <malloc.h>
  51 # else
  52 void free ();
  53 # endif
  54 #endif
  55
  56 #if defined HAVE_STRING_H || defined _LIBC
  57 # include <string.h>
  58 #else
  59 # include <strings.h>
  60 #endif
  61 #if !HAVE_STRCHR && !defined _LIBC
  62 # ifndef strchr
  63 #  define strchr index
  64 # endif
  65 #endif
  66
  67 #if defined HAVE_UNISTD_H || defined _LIBC
  68 # include <unistd.h>
  69 #endif
  70
  71 #include "gettext.h"
  72 #include "gettextP.h"
  73 #ifdef _LIBC
  74 # include <libintl.h>
  75 #else
  76 # include "libgettext.h"
  77 #endif
  78 #include "hash-string.h"
  79
  80 /* @@ end of prolog @@ */
  81
  82 #ifdef _LIBC
  83 /* Rename the non ANSI C functions.  This is required by the standard
  84    because some ANSI C functions will require linking with this object
  85    file and the name space must not be polluted.  */
  86 # define getcwd __getcwd
  87 # define stpcpy __stpcpy
  88 #endif
  89
  90 #if !defined HAVE_GETCWD && !defined _LIBC
  91 char *getwd ();
  92 # define getcwd(buf, max) getwd (buf)
  93 #else
  94 char *getcwd ();
  95 #endif
  96
  97 /* Amount to increase buffer size by in each try.  */
  98 #define PATH_INCR 32
  99
 100 /* The following is from pathmax.h.  */
 101 /* Non-POSIX BSD systems might have gcc's limits.h, which doesn't define
 102    PATH_MAX but might cause redefinition warnings when sys/param.h is
 103    later included (as on MORE/BSD 4.3).  */
 104 #if defined(_POSIX_VERSION) || (defined(HAVE_LIMITS_H) && !defined(__GNUC__))
 105 # include <limits.h>
 106 #endif
 107
 108 #ifndef _POSIX_PATH_MAX
 109 # define _POSIX_PATH_MAX 255
 110 #endif
 111
 112 #if !defined(PATH_MAX) && defined(_PC_PATH_MAX)
 113 # define PATH_MAX (pathconf ("/", _PC_PATH_MAX) < 1 ? 1024 : pathconf ("/", _PC_PATH_MAX))
 114 #endif
 115
 116 /* Don't include sys/param.h if it already has been.  */
 117 #if defined(HAVE_SYS_PARAM_H) && !defined(PATH_MAX) && !defined(MAXPATHLEN)
 118 # include <sys/param.h>
 119 #endif
 120
 121 #if !defined(PATH_MAX) && defined(MAXPATHLEN)
 122 # define PATH_MAX MAXPATHLEN
 123 #endif
 124
 125 #ifndef PATH_MAX
 126 # define PATH_MAX _POSIX_PATH_MAX
 127 #endif
 128
 129 /* XPG3 defines the result of `setlocale (category, NULL)' as:
 130    ``Directs `setlocale()' to query `category' and return the current
 131      setting of `local'.''
 132    However it does not specify the exact format.  And even worse: POSIX
 133    defines this not at all.  So we can use this feature only on selected
 134    system (e.g. those using GNU C Library).  */
 135 #ifdef _LIBC
 136 # define HAVE_LOCALE_NULL
 137 #endif
 138
 139 /* Name of the default domain used for gettext(3) prior any call to
 140    textdomain(3).  The default value for this is "messages".  */
 141 const char _nl_default_default_domain[] = "messages";
 142
 143 /* Value used as the default domain for gettext(3).  */
 144 const char *_nl_current_default_domain = _nl_default_default_domain;
 145
 146 /* Contains the default location of the message catalogs.  */
 147 const char _nl_default_dirname[] = GNULOCALEDIR;
 148
 149 /* List with bindings of specific domains created by bindtextdomain()
 150    calls.  */
 151 struct binding *_nl_domain_bindings;
 152
 153 /* Prototypes for local functions.  */
 154 static char *find_msg __P ((struct loaded_domain *domain, const char *msgid));
 155 static const char *category_to_name __P((int category));
 156 static const char *guess_category_value __P((int category,
 157                                              const char *categoryname));
 158
 159
 160 /* Names for the libintl functions are a problem.  They must not clash
 161    with existing names and they should follow ANSI C.  But this source
 162    code is also used in GNU C Library where the names have a __
 163    prefix.  So we have to make a difference here.  */
 164 #ifdef _LIBC
 165 # define DCGETTEXT __dcgettext
 166 #else
 167 # define DCGETTEXT dcgettext__
 168 #endif
 169
 170 /* Look up MSGID in the DOMAINNAME message catalog for the current CATEGORY
 171    locale.  */
 172 char *
 173 DCGETTEXT (domainname, msgid, category)
 174      const char *domainname;
 175      const char *msgid;
 176      int category;
 177 {
 178   struct loaded_domain *domain;
 179   struct binding *binding;
 180   const char *categoryname;
 181   const char *categoryvalue;
 182   char *dirname, *xdomainname;
 183   char *single_locale;
 184   char *retval;
 185
 186   /* If no real MSGID is given return NULL.  */
 187   if (msgid == NULL)
 188     return NULL;
 189
 190   /* If DOMAINNAME is NULL, we are interested in the default domain.  If
 191      CATEGORY is not LC_MESSAGES this might not make much sense but the
 192      defintion left this undefined.  */
 193   if (domainname == NULL)
 194     domainname = _nl_current_default_domain;
 195
 196   /* First find matching binding.  */
 197   for (binding = _nl_domain_bindings; binding != NULL; binding = binding->next)
 198     {
 199       int compare = strcmp (domainname, binding->domainname);
 200       if (compare == 0)
 201         /* We found it!  */
 202         break;
 203       if (compare < 0)
 204         {
 205           /* It is not in the list.  */
 206           binding = NULL;
 207           break;
 208         }
 209     }
 210
 211   if (binding == NULL)
 212     dirname = (char *) _nl_default_dirname;
 213   else if (binding->dirname[0] == '/')
 214     dirname = binding->dirname;
 215   else
 216     {
 217       /* We have a relative path.  Make it absolute now.  */
 218       size_t dirname_len = strlen (binding->dirname) + 1;
 219       size_t path_max;
 220       char *ret;
 221
 222       path_max = (unsigned) PATH_MAX;
 223       path_max += 2;            /* The getcwd docs say to do this.  */
 224
 225       dirname = (char *) alloca (path_max + dirname_len);
 226
 227       errno = 0;
 228       while ((ret = getcwd (dirname, path_max)) == NULL && errno == ERANGE)
 229         {
 230           path_max += PATH_INCR;
 231           dirname = (char *) alloca (path_max + dirname_len);
 232           errno = 0;
 233         }
 234
 235       if (ret == NULL)
 236         /* We cannot get the current working directory.  Don't signal an
 237            error but simply return the default string.  */
 238         return (char *) msgid;
 239
 240       /* We don't want libintl.a to depend on any other library.  So
 241          we avoid the non-standard function stpcpy.  In GNU C Library
 242          this function is available, though.  Also allow the symbol
 243          HAVE_STPCPY to be defined.  */
 244 #if defined _LIBC || defined HAVE_STPCPY
 245       stpcpy (stpcpy (strchr (dirname, '\0'), "/"), binding->dirname);
 246 #else
 247       strcat (dirname, "/");
 248       strcat (dirname, binding->dirname);
 249 #endif
 250     }
 251
 252   /* Now determine the symbolic name of CATEGORY and its value.  */
 253   categoryname = category_to_name (category);
 254   categoryvalue = guess_category_value (category, categoryname);
 255
 256   xdomainname = (char *) alloca (strlen (categoryname)
 257                                  + strlen (domainname) + 5);
 258   /* We don't want libintl.a to depend on any other library.  So we
 259      avoid the non-standard function stpcpy.  In GNU C Library this
 260      function is available, though.  Also allow the symbol HAVE_STPCPY
 261      to be defined.  */
 262 #if defined _LIBC || defined HAVE_STPCPY
 263   stpcpy (stpcpy (stpcpy (stpcpy (xdomainname, categoryname), "/"),
 264                   domainname),
 265           ".mo");
 266 #else
 267   strcpy (xdomainname, categoryname);
 268   strcat (xdomainname, "/");
 269   strcat (xdomainname, domainname);
 270   strcat (xdomainname, ".mo");
 271 #endif
 272
 273   /* Creating working area.  */
 274   single_locale = (char *) alloca (strlen (categoryvalue) + 1);
 275
 276
 277   /* Search for the given string.  This is a loop because we perhaps
 278      got an ordered list of languages to consider for th translation.  */
 279   while (1)
 280     {
 281       /* Make CATEGORYVALUE point to the next element of the list.  */
 282       while (categoryvalue[0] != '\0' && categoryvalue[0] == ':')
 283         ++categoryvalue;
 284       if (categoryvalue[0] == '\0')
 285         {
 286           /* The whole contents of CATEGORYVALUE has been searched but
 287              no valid entry has been found.  We solve this situation
 288              by implicitely appending a "C" entry, i.e. no translation
 289              will take place.  */
 290           single_locale[0] = 'C';
 291           single_locale[1] = '\0';
 292         }
 293       else
 294         {
 295           char *cp = single_locale;
 296           while (categoryvalue[0] != '\0' && categoryvalue[0] != ':')
 297             *cp++ = *categoryvalue++;
 298           *cp = '\0';
 299         }
 300
 301       /* If the current locale value is C (or POSIX) we don't load a
 302          domain.  Return the MSGID.  */
 303       if (strcmp (single_locale, "C") == 0
 304           || strcmp (single_locale, "POSIX") == 0)
 305         return (char *) msgid;
 306
 307
 308       /* Find structure describing the message catalog matching the
 309          DOMAINNAME and CATEGORY.  */
 310       domain = _nl_find_domain (dirname, single_locale, xdomainname);
 311
 312       if (domain != NULL)
 313         {
 314           retval = find_msg (domain, msgid);
 315
 316           if (retval == NULL)
 317             {
 318               int cnt;
 319
 320               for (cnt = 0; domain->successor[cnt] != NULL; ++cnt)
 321                 {
 322                   retval = find_msg (domain->successor[cnt], msgid);
 323
 324                   if (retval != NULL)
 325                     break;
 326                 }
 327             }
 328
 329           if (retval != NULL)
 330             return retval;
 331         }
 332     }
 333   /* NOTREACHED */
 334 }
 335
 336 #ifdef _LIBC
 337 /* Alias for function name in GNU C Library.  */
 338 weak_alias (__dcgettext, dcgettext);
 339 #endif
 340
 341
 342 static char *
 343 find_msg (domain, msgid)
 344      struct loaded_domain *domain;
 345      const char *msgid;
 346 {
 347   size_t top, act, bottom;
 348
 349   if (domain->decided == 0)
 350     _nl_load_domain (domain);
 351
 352   if (domain->data == NULL)
 353     return NULL;
 354
 355   /* Locate the MSGID and its translation.  */
 356   if (domain->hash_size > 2 && domain->hash_tab != NULL)
 357     {
 358       /* Use the hashing table.  */
 359       nls_uint32 len = strlen (msgid);
 360       nls_uint32 hash_val = hash_string (msgid);
 361       nls_uint32 idx = hash_val % domain->hash_size;
 362       nls_uint32 incr = 1 + (hash_val % (domain->hash_size - 2));
 363       nls_uint32 nstr = W (domain->must_swap, domain->hash_tab[idx]);
 364
 365       if (nstr == 0)
 366         /* Hash table entry is empty.  */
 367         return NULL;
 368
 369       if (W (domain->must_swap, domain->orig_tab[nstr - 1].length) == len
 370           && strcmp (msgid,
 371                      domain->data + W (domain->must_swap,
 372                                        domain->orig_tab[nstr - 1].offset)) == 0)
 373         return (char *) domain->data + W (domain->must_swap,
 374                                           domain->trans_tab[nstr - 1].offset);
 375
 376       while (1)
 377         {
 378           if (idx >= W (domain->must_swap, domain->hash_size) - incr)
 379             idx -= W (domain->must_swap, domain->hash_size) - incr;
 380           else
 381             idx += incr;
 382
 383           nstr = W (domain->must_swap, domain->hash_tab[idx]);
 384           if (nstr == 0)
 385             /* Hash table entry is empty.  */
 386             return NULL;
 387
 388           if (W (domain->must_swap, domain->orig_tab[nstr - 1].length) == len
 389               && strcmp (msgid,
 390                          domain->data + W (domain->must_swap,
 391                                            domain->orig_tab[nstr - 1].offset))
 392                  == 0)
 393             return (char *) domain->data
 394               + W (domain->must_swap, domain->trans_tab[nstr - 1].offset);
 395         }
 396       /* NOTREACHED */
 397     }
 398
 399   /* Now we try the default method:  binary search in the sorted
 400      array of messages.  */
 401   bottom = 0;
 402   top = domain->nstrings;
 403   while (bottom < top)
 404     {
 405       int cmp_val;
 406
 407       act = (bottom + top) / 2;
 408       cmp_val = strcmp (msgid, domain->data
 409                                + W (domain->must_swap,
 410                                     domain->orig_tab[act].offset));
 411       if (cmp_val < 0)
 412         top = act;
 413       else if (cmp_val > 0)
 414         bottom = act + 1;
 415       else
 416         break;
 417     }
 418
 419   /* If an translation is found return this.  */
 420   return bottom >= top ? NULL : (char *) domain->data
 421                                 + W (domain->must_swap,
 422                                      domain->trans_tab[act].offset);
 423 }
 424
 425
 426 /* Return string representation of locale CATEGORY.  */
 427 static const char *category_to_name (category)
 428      int category;
 429 {
 430   const char *retval;
 431
 432   switch (category)
 433   {
 434 #ifdef LC_COLLATE
 435   case LC_COLLATE:
 436     retval = "LC_COLLATE";
 437     break;
 438 #endif
 439 #ifdef LC_CTYPE
 440   case LC_CTYPE:
 441     retval = "LC_CTYPE";
 442     break;
 443 #endif
 444 #ifdef LC_MONETARY
 445   case LC_MONETARY:
 446     retval = "LC_MONETARY";
 447     break;
 448 #endif
 449 #ifdef LC_NUMERIC
 450   case LC_NUMERIC:
 451     retval = "LC_NUMERIC";
 452     break;
 453 #endif
 454 #ifdef LC_TIME
 455   case LC_TIME:
 456     retval = "LC_TIME";
 457     break;
 458 #endif
 459 #ifdef LC_MESSAGES
 460   case LC_MESSAGES:
 461     retval = "LC_MESSAGES";
 462     break;
 463 #endif
 464 #ifdef LC_RESPONSE
 465   case LC_RESPONSE:
 466     retval = "LC_RESPONSE";
 467     break;
 468 #endif
 469 #ifdef LC_ALL
 470   case LC_ALL:
 471     /* This might not make sense but is perhaps better than any other
 472        value.  */
 473     retval = "LC_ALL";
 474     break;
 475 #endif
 476   default:
 477     /* If you have a better idea for a default value let me know.  */
 478     retval = "LC_XXX";
 479   }
 480
 481   return retval;
 482 }
 483
 484 /* Guess value of current locale from value of the environment variables.  */
 485 static const char *guess_category_value (category, categoryname)
 486      int category;
 487      const char *categoryname;
 488 {
 489   const char *retval;
 490
 491   /* The highest priority value is the `LANGUAGE' environment
 492      variable.  This is a GNU extension.  */
 493   retval = getenv ("LANGUAGE");
 494   if (retval != NULL && retval[0] != '\0')
 495     return retval;
 496
 497   /* `LANGUAGE' is not set.  So we have to proceed with the POSIX
 498      methods of looking to `LC_ALL', `LC_xxx', and `LANG'.  On some
 499      systems this can be done by the `setlocale' function itself.  */
 500 #if defined HAVE_SETLOCALE && defined HAVE_LC_MESSAGES && defined HAVE_LOCALE_NULL
 501   return setlocale (category, NULL);
 502 #else
 503   /* Setting of LC_ALL overwrites all other.  */
 504   retval = getenv ("LC_ALL");
 505   if (retval != NULL && retval[0] != '\0')
 506     return retval;
 507
 508   /* Next comes the name of the desired category.  */
 509   retval = getenv (categoryname);
 510   if (retval != NULL && retval[0] != '\0')
 511     return retval;
 512
 513   /* Last possibility is the LANG environment variable.  */
 514   retval = getenv ("LANG");
 515   if (retval != NULL && retval[0] != '\0')
 516     return retval;
 517
 518   /* We use C as the default domain.  POSIX says this is implementation
 519      defined.  */
 520   return "C";
 521 #endif
 522 }