intl/dcgettext.c

   1 /* Implementation of the dcgettext(3) function
   2    Copyright (C) 1995, 1996, 1997 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 Foundation,
  16    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 # define HAVE_ALLOCA 1
  27 #else
  28 # if defined HAVE_ALLOCA_H || defined _LIBC
  29 #  include <alloca.h>
  30 # else
  31 #  ifdef _AIX
  32  #pragma alloca
  33 #  else
  34 #   ifndef alloca
  35 char *alloca ();
  36 #   endif
  37 #  endif
  38 # endif
  39 #endif
  40
  41 #include <errno.h>
  42 #ifndef errno
  43 extern int errno;
  44 #endif
  45 #ifndef __set_errno
  46 # define __set_errno(val) errno = (val)
  47 #endif
  48
  49 #if defined STDC_HEADERS || defined _LIBC
  50 # include <stdlib.h>
  51 #else
  52 char *getenv ();
  53 # ifdef HAVE_MALLOC_H
  54 #  include <malloc.h>
  55 # else
  56 void free ();
  57 # endif
  58 #endif
  59
  60 #if defined HAVE_STRING_H || defined _LIBC
  61 # ifndef _GNU_SOURCE
  62 #  define _GNU_SOURCE   1
  63 # endif
  64 # include <string.h>
  65 #else
  66 # include <strings.h>
  67 #endif
  68 #if !HAVE_STRCHR && !defined _LIBC
  69 # ifndef strchr
  70 #  define strchr index
  71 # endif
  72 #endif
  73
  74 #if defined HAVE_UNISTD_H || defined _LIBC
  75 # include <unistd.h>
  76 #endif
  77
  78 #include "gettext.h"
  79 #include "gettextP.h"
  80 #ifdef _LIBC
  81 # include <libintl.h>
  82 #else
  83 # include "libgettext.h"
  84 #endif
  85 #include "hash-string.h"
  86
  87 /* @@ end of prolog @@ */
  88
  89 #ifdef _LIBC
  90 /* Rename the non ANSI C functions.  This is required by the standard
  91    because some ANSI C functions will require linking with this object
  92    file and the name space must not be polluted.  */
  93 # define getcwd __getcwd
  94 # define stpcpy __stpcpy
  95 #else
  96 # if !defined HAVE_GETCWD
  97 char *getwd ();
  98 #  define getcwd(buf, max) getwd (buf)
  99 # else
 100 char *getcwd ();
 101 # endif
 102 # ifndef HAVE_STPCPY
 103 static char *stpcpy PARAMS ((char *dest, const char *src));
 104 # endif
 105 #endif
 106
 107 /* Amount to increase buffer size by in each try.  */
 108 #define PATH_INCR 32
 109
 110 /* The following is from pathmax.h.  */
 111 /* Non-POSIX BSD systems might have gcc's limits.h, which doesn't define
 112    PATH_MAX but might cause redefinition warnings when sys/param.h is
 113    later included (as on MORE/BSD 4.3).  */
 114 #if defined(_POSIX_VERSION) || (defined(HAVE_LIMITS_H) && !defined(__GNUC__))
 115 # include <limits.h>
 116 #endif
 117
 118 #ifndef _POSIX_PATH_MAX
 119 # define _POSIX_PATH_MAX 255
 120 #endif
 121
 122 #if !defined(PATH_MAX) && defined(_PC_PATH_MAX)
 123 # define PATH_MAX (pathconf ("/", _PC_PATH_MAX) < 1 ? 1024 : pathconf ("/", _PC_PATH_MAX))
 124 #endif
 125
 126 /* Don't include sys/param.h if it already has been.  */
 127 #if defined(HAVE_SYS_PARAM_H) && !defined(PATH_MAX) && !defined(MAXPATHLEN)
 128 # include <sys/param.h>
 129 #endif
 130
 131 #if !defined(PATH_MAX) && defined(MAXPATHLEN)
 132 # define PATH_MAX MAXPATHLEN
 133 #endif
 134
 135 #ifndef PATH_MAX
 136 # define PATH_MAX _POSIX_PATH_MAX
 137 #endif
 138
 139 /* XPG3 defines the result of `setlocale (category, NULL)' as:
 140    ``Directs `setlocale()' to query `category' and return the current
 141      setting of `local'.''
 142    However it does not specify the exact format.  And even worse: POSIX
 143    defines this not at all.  So we can use this feature only on selected
 144    system (e.g. those using GNU C Library).  */
 145 #ifdef _LIBC
 146 # define HAVE_LOCALE_NULL
 147 #endif
 148
 149 /* Name of the default domain used for gettext(3) prior any call to
 150    textdomain(3).  The default value for this is "messages".  */
 151 const char _nl_default_default_domain[] = "messages";
 152
 153 /* Value used as the default domain for gettext(3).  */
 154 const char *_nl_current_default_domain = _nl_default_default_domain;
 155
 156 /* Contains the default location of the message catalogs.  */
 157 const char _nl_default_dirname[] = GNULOCALEDIR;
 158
 159 /* List with bindings of specific domains created by bindtextdomain()
 160    calls.  */
 161 struct binding *_nl_domain_bindings;
 162
 163 /* Prototypes for local functions.  */
 164 static char *find_msg PARAMS ((struct loaded_l10nfile *domain_file,
 165                                const char *msgid));
 166 static const char *category_to_name PARAMS ((int category));
 167 static const char *guess_category_value PARAMS ((int category,
 168                                                  const char *categoryname));
 169
 170
 171 /* For those loosing systems which don't have `alloca' we have to add
 172    some additional code emulating it.  */
 173 #ifdef HAVE_ALLOCA
 174 /* Nothing has to be done.  */
 175 # define ADD_BLOCK(list, address) /* nothing */
 176 # define FREE_BLOCKS(list) /* nothing */
 177 #else
 178 struct block_list
 179 {
 180   void *address;
 181   struct block_list *next;
 182 };
 183 # define ADD_BLOCK(list, addr)                                                \
 184   do {                                                                        \
 185     struct block_list *newp = (struct block_list *) malloc (sizeof (*newp));  \
 186     /* If we cannot get a free block we cannot add the new element to         \
 187        the list.  */                                                          \
 188     if (newp != NULL) {                                                       \
 189       newp->address = (addr);                                                 \
 190       newp->next = (list);                                                    \
 191       (list) = newp;                                                          \
 192     }                                                                         \
 193   } while (0)
 194 # define FREE_BLOCKS(list)                                                    \
 195   do {                                                                        \
 196     while (list != NULL) {                                                    \
 197       struct block_list *old = list;                                          \
 198       list = list->next;                                                      \
 199       free (old);                                                             \
 200     }                                                                         \
 201   } while (0)
 202 # undef alloca
 203 # define alloca(size) (malloc (size))
 204 #endif  /* have alloca */
 205
 206
 207 /* Names for the libintl functions are a problem.  They must not clash
 208    with existing names and they should follow ANSI C.  But this source
 209    code is also used in GNU C Library where the names have a __
 210    prefix.  So we have to make a difference here.  */
 211 #ifdef _LIBC
 212 # define DCGETTEXT __dcgettext
 213 #else
 214 # define DCGETTEXT dcgettext__
 215 #endif
 216
 217 /* Look up MSGID in the DOMAINNAME message catalog for the current CATEGORY
 218    locale.  */
 219 char *
 220 DCGETTEXT (domainname, msgid, category)
 221      const char *domainname;
 222      const char *msgid;
 223      int category;
 224 {
 225 #ifndef HAVE_ALLOCA
 226   struct block_list *block_list = NULL;
 227 #endif
 228   struct loaded_l10nfile *domain;
 229   struct binding *binding;
 230   const char *categoryname;
 231   const char *categoryvalue;
 232   char *dirname, *xdomainname;
 233   char *single_locale;
 234   char *retval;
 235   int saved_errno = errno;
 236
 237   /* If no real MSGID is given return NULL.  */
 238   if (msgid == NULL)
 239     return NULL;
 240
 241   /* If DOMAINNAME is NULL, we are interested in the default domain.  If
 242      CATEGORY is not LC_MESSAGES this might not make much sense but the
 243      defintion left this undefined.  */
 244   if (domainname == NULL)
 245     domainname = _nl_current_default_domain;
 246
 247   /* First find matching binding.  */
 248   for (binding = _nl_domain_bindings; binding != NULL; binding = binding->next)
 249     {
 250       int compare = strcmp (domainname, binding->domainname);
 251       if (compare == 0)
 252         /* We found it!  */
 253         break;
 254       if (compare < 0)
 255         {
 256           /* It is not in the list.  */
 257           binding = NULL;
 258           break;
 259         }
 260     }
 261
 262   if (binding == NULL)
 263     dirname = (char *) _nl_default_dirname;
 264   else if (binding->dirname[0] == '/')
 265     dirname = binding->dirname;
 266   else
 267     {
 268       /* We have a relative path.  Make it absolute now.  */
 269       size_t dirname_len = strlen (binding->dirname) + 1;
 270       size_t path_max;
 271       char *ret;
 272
 273       path_max = (unsigned) PATH_MAX;
 274       path_max += 2;            /* The getcwd docs say to do this.  */
 275
 276       dirname = (char *) alloca (path_max + dirname_len);
 277       ADD_BLOCK (block_list, dirname);
 278
 279       __set_errno (0);
 280       while ((ret = getcwd (dirname, path_max)) == NULL && errno == ERANGE)
 281         {
 282           path_max += PATH_INCR;
 283           dirname = (char *) alloca (path_max + dirname_len);
 284           ADD_BLOCK (block_list, dirname);
 285           __set_errno (0);
 286         }
 287
 288       if (ret == NULL)
 289         {
 290           /* We cannot get the current working directory.  Don't signal an
 291              error but simply return the default string.  */
 292           FREE_BLOCKS (block_list);
 293           __set_errno (saved_errno);
 294           return (char *) msgid;
 295         }
 296
 297       stpcpy (stpcpy (strchr (dirname, '\0'), "/"), binding->dirname);
 298     }
 299
 300   /* Now determine the symbolic name of CATEGORY and its value.  */
 301   categoryname = category_to_name (category);
 302   categoryvalue = guess_category_value (category, categoryname);
 303
 304   xdomainname = (char *) alloca (strlen (categoryname)
 305                                  + strlen (domainname) + 5);
 306   ADD_BLOCK (block_list, xdomainname);
 307
 308   stpcpy (stpcpy (stpcpy (stpcpy (xdomainname, categoryname), "/"),
 309                   domainname),
 310           ".mo");
 311
 312   /* Creating working area.  */
 313   single_locale = (char *) alloca (strlen (categoryvalue) + 1);
 314   ADD_BLOCK (block_list, single_locale);
 315
 316
 317   /* Search for the given string.  This is a loop because we perhaps
 318      got an ordered list of languages to consider for th translation.  */
 319   while (1)
 320     {
 321       /* Make CATEGORYVALUE point to the next element of the list.  */
 322       while (categoryvalue[0] != '\0' && categoryvalue[0] == ':')
 323         ++categoryvalue;
 324       if (categoryvalue[0] == '\0')
 325         {
 326           /* The whole contents of CATEGORYVALUE has been searched but
 327              no valid entry has been found.  We solve this situation
 328              by implicitly appending a "C" entry, i.e. no translation
 329              will take place.  */
 330           single_locale[0] = 'C';
 331           single_locale[1] = '\0';
 332         }
 333       else
 334         {
 335           char *cp = single_locale;
 336           while (categoryvalue[0] != '\0' && categoryvalue[0] != ':')
 337             *cp++ = *categoryvalue++;
 338           *cp = '\0';
 339         }
 340
 341       /* If the current locale value is C (or POSIX) we don't load a
 342          domain.  Return the MSGID.  */
 343       if (strcmp (single_locale, "C") == 0
 344           || strcmp (single_locale, "POSIX") == 0)
 345         {
 346           FREE_BLOCKS (block_list);
 347           __set_errno (saved_errno);
 348           return (char *) msgid;
 349         }
 350
 351
 352       /* Find structure describing the message catalog matching the
 353          DOMAINNAME and CATEGORY.  */
 354       domain = _nl_find_domain (dirname, single_locale, xdomainname);
 355
 356       if (domain != NULL)
 357         {
 358           retval = find_msg (domain, msgid);
 359
 360           if (retval == NULL)
 361             {
 362               int cnt;
 363
 364               for (cnt = 0; domain->successor[cnt] != NULL; ++cnt)
 365                 {
 366                   retval = find_msg (domain->successor[cnt], msgid);
 367
 368                   if (retval != NULL)
 369                     break;
 370                 }
 371             }
 372
 373           if (retval != NULL)
 374             {
 375               FREE_BLOCKS (block_list);
 376               __set_errno (saved_errno);
 377               return retval;
 378             }
 379         }
 380     }
 381   /* NOTREACHED */
 382 }
 383
 384 #ifdef _LIBC
 385 /* Alias for function name in GNU C Library.  */
 386 weak_alias (__dcgettext, dcgettext);
 387 #endif
 388
 389
 390 static char *
 391 find_msg (domain_file, msgid)
 392      struct loaded_l10nfile *domain_file;
 393      const char *msgid;
 394 {
 395   size_t top, act, bottom;
 396   struct loaded_domain *domain;
 397
 398   if (domain_file->decided == 0)
 399     _nl_load_domain (domain_file);
 400
 401   if (domain_file->data == NULL)
 402     return NULL;
 403
 404   domain = (struct loaded_domain *) domain_file->data;
 405
 406   /* Locate the MSGID and its translation.  */
 407   if (domain->hash_size > 2 && domain->hash_tab != NULL)
 408     {
 409       /* Use the hashing table.  */
 410       nls_uint32 len = strlen (msgid);
 411       nls_uint32 hash_val = hash_string (msgid);
 412       nls_uint32 idx = hash_val % domain->hash_size;
 413       nls_uint32 incr = 1 + (hash_val % (domain->hash_size - 2));
 414       nls_uint32 nstr = W (domain->must_swap, domain->hash_tab[idx]);
 415
 416       if (nstr == 0)
 417         /* Hash table entry is empty.  */
 418         return NULL;
 419
 420       if (W (domain->must_swap, domain->orig_tab[nstr - 1].length) == len
 421           && strcmp (msgid,
 422                      domain->data + W (domain->must_swap,
 423                                        domain->orig_tab[nstr - 1].offset)) == 0)
 424         return (char *) domain->data + W (domain->must_swap,
 425                                           domain->trans_tab[nstr - 1].offset);
 426
 427       while (1)
 428         {
 429           if (idx >= domain->hash_size - incr)
 430             idx -= domain->hash_size - incr;
 431           else
 432             idx += incr;
 433
 434           nstr = W (domain->must_swap, domain->hash_tab[idx]);
 435           if (nstr == 0)
 436             /* Hash table entry is empty.  */
 437             return NULL;
 438
 439           if (W (domain->must_swap, domain->orig_tab[nstr - 1].length) == len
 440               && strcmp (msgid,
 441                          domain->data + W (domain->must_swap,
 442                                            domain->orig_tab[nstr - 1].offset))
 443                  == 0)
 444             return (char *) domain->data
 445               + W (domain->must_swap, domain->trans_tab[nstr - 1].offset);
 446         }
 447       /* NOTREACHED */
 448     }
 449
 450   /* Now we try the default method:  binary search in the sorted
 451      array of messages.  */
 452   bottom = 0;
 453   top = domain->nstrings;
 454   while (bottom < top)
 455     {
 456       int cmp_val;
 457
 458       act = (bottom + top) / 2;
 459       cmp_val = strcmp (msgid, domain->data
 460                                + W (domain->must_swap,
 461                                     domain->orig_tab[act].offset));
 462       if (cmp_val < 0)
 463         top = act;
 464       else if (cmp_val > 0)
 465         bottom = act + 1;
 466       else
 467         break;
 468     }
 469
 470   /* If an translation is found return this.  */
 471   return bottom >= top ? NULL : (char *) domain->data
 472                                 + W (domain->must_swap,
 473                                      domain->trans_tab[act].offset);
 474 }
 475
 476
 477 /* Return string representation of locale CATEGORY.  */
 478 static const char *
 479 category_to_name (category)
 480      int category;
 481 {
 482   const char *retval;
 483
 484   switch (category)
 485   {
 486 #ifdef LC_COLLATE
 487   case LC_COLLATE:
 488     retval = "LC_COLLATE";
 489     break;
 490 #endif
 491 #ifdef LC_CTYPE
 492   case LC_CTYPE:
 493     retval = "LC_CTYPE";
 494     break;
 495 #endif
 496 #ifdef LC_MONETARY
 497   case LC_MONETARY:
 498     retval = "LC_MONETARY";
 499     break;
 500 #endif
 501 #ifdef LC_NUMERIC
 502   case LC_NUMERIC:
 503     retval = "LC_NUMERIC";
 504     break;
 505 #endif
 506 #ifdef LC_TIME
 507   case LC_TIME:
 508     retval = "LC_TIME";
 509     break;
 510 #endif
 511 #ifdef LC_MESSAGES
 512   case LC_MESSAGES:
 513     retval = "LC_MESSAGES";
 514     break;
 515 #endif
 516 #ifdef LC_RESPONSE
 517   case LC_RESPONSE:
 518     retval = "LC_RESPONSE";
 519     break;
 520 #endif
 521 #ifdef LC_ALL
 522   case LC_ALL:
 523     /* This might not make sense but is perhaps better than any other
 524        value.  */
 525     retval = "LC_ALL";
 526     break;
 527 #endif
 528   default:
 529     /* If you have a better idea for a default value let me know.  */
 530     retval = "LC_XXX";
 531   }
 532
 533   return retval;
 534 }
 535
 536 /* Guess value of current locale from value of the environment variables.  */
 537 static const char *
 538 guess_category_value (category, categoryname)
 539      int category;
 540      const char *categoryname;
 541 {
 542   const char *retval;
 543
 544   /* The highest priority value is the `LANGUAGE' environment
 545      variable.  This is a GNU extension.  */
 546   retval = getenv ("LANGUAGE");
 547   if (retval != NULL && retval[0] != '\0')
 548     return retval;
 549
 550   /* `LANGUAGE' is not set.  So we have to proceed with the POSIX
 551      methods of looking to `LC_ALL', `LC_xxx', and `LANG'.  On some
 552      systems this can be done by the `setlocale' function itself.  */
 553 #if defined HAVE_SETLOCALE && defined HAVE_LC_MESSAGES && defined HAVE_LOCALE_NULL
 554   return setlocale (category, NULL);
 555 #else
 556   /* Setting of LC_ALL overwrites all other.  */
 557   retval = getenv ("LC_ALL");
 558   if (retval != NULL && retval[0] != '\0')
 559     return retval;
 560
 561   /* Next comes the name of the desired category.  */
 562   retval = getenv (categoryname);
 563   if (retval != NULL && retval[0] != '\0')
 564     return retval;
 565
 566   /* Last possibility is the LANG environment variable.  */
 567   retval = getenv ("LANG");
 568   if (retval != NULL && retval[0] != '\0')
 569     return retval;
 570
 571   /* We use C as the default domain.  POSIX says this is implementation
 572      defined.  */
 573   return "C";
 574 #endif
 575 }
 576
 577 /* @@ begin of epilog @@ */
 578
 579 /* We don't want libintl.a to depend on any other library.  So we
 580    avoid the non-standard function stpcpy.  In GNU C Library this
 581    function is available, though.  Also allow the symbol HAVE_STPCPY
 582    to be defined.  */
 583 #if !_LIBC && !HAVE_STPCPY
 584 static char *
 585 stpcpy (dest, src)
 586      char *dest;
 587      const char *src;
 588 {
 589   while ((*dest++ = *src++) != '\0')
 590     /* Do nothing. */ ;
 591   return dest - 1;
 592 }
 593 #endif