| /* Determine a canonical name for the current locale's character encoding. |
| |
| Copyright (C) 2000-2001 Free Software Foundation, Inc. |
| |
| This program is free software; you can redistribute it and/or modify it |
| under the terms of the GNU Library General Public License as published |
| by the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| This program is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public |
| License along with this program; if not, write to the Free Software |
| Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, |
| USA. */ |
| |
| /* Written by Bruno Haible <haible@clisp.cons.org>. */ |
| |
| #ifdef HAVE_CONFIG_H |
| # include <config.h> |
| #endif |
| |
| #if HAVE_STDDEF_H |
| # include <stddef.h> |
| #endif |
| |
| #include <stdio.h> |
| #if HAVE_STRING_H |
| # include <string.h> |
| #else |
| # include <strings.h> |
| #endif |
| #if HAVE_STDLIB_H |
| # include <stdlib.h> |
| #endif |
| |
| #if defined _WIN32 || defined __WIN32__ |
| # undef WIN32 /* avoid warning on mingw32 */ |
| # define WIN32 |
| #endif |
| |
| #ifndef WIN32 |
| # if HAVE_LANGINFO_CODESET |
| # include <langinfo.h> |
| # else |
| # if HAVE_SETLOCALE |
| # include <locale.h> |
| # endif |
| # endif |
| #else /* WIN32 */ |
| # define WIN32_LEAN_AND_MEAN |
| # include <windows.h> |
| #endif |
| |
| #ifndef DIRECTORY_SEPARATOR |
| # define DIRECTORY_SEPARATOR '/' |
| #endif |
| |
| #ifndef ISSLASH |
| # define ISSLASH(C) ((C) == DIRECTORY_SEPARATOR) |
| #endif |
| |
| /* The following static variable is declared 'volatile' to avoid a |
| possible multithread problem in the function get_charset_aliases. If we |
| are running in a threaded environment, and if two threads initialize |
| 'charset_aliases' simultaneously, both will produce the same value, |
| and everything will be ok if the two assignments to 'charset_aliases' |
| are atomic. But I don't know what will happen if the two assignments mix. */ |
| #if __STDC__ != 1 |
| # define volatile /* empty */ |
| #endif |
| /* Pointer to the contents of the charset.alias file, if it has already been |
| read, else NULL. Its format is: |
| ALIAS_1 '\0' CANONICAL_1 '\0' ... ALIAS_n '\0' CANONICAL_n '\0' '\0' */ |
| static const char * volatile charset_aliases; |
| |
| /* Return a pointer to the contents of the charset.alias file. */ |
| static const char * |
| get_charset_aliases () |
| { |
| const char *cp; |
| |
| cp = charset_aliases; |
| if (cp == NULL) |
| { |
| #ifndef WIN32 |
| FILE *fp; |
| const char *dir = LIBDIR; |
| const char *base = "charset.alias"; |
| char *file_name; |
| |
| /* Concatenate dir and base into freshly allocated file_name. */ |
| { |
| size_t dir_len = strlen (dir); |
| size_t base_len = strlen (base); |
| int add_slash = (dir_len > 0 && !ISSLASH (dir[dir_len - 1])); |
| file_name = (char *) malloc (dir_len + add_slash + base_len + 1); |
| if (file_name != NULL) |
| { |
| memcpy (file_name, dir, dir_len); |
| if (add_slash) |
| file_name[dir_len] = DIRECTORY_SEPARATOR; |
| memcpy (file_name + dir_len + add_slash, base, base_len + 1); |
| } |
| } |
| |
| if (file_name == NULL || (fp = fopen (file_name, "r")) == NULL) |
| /* Out of memory or file not found, treat it as empty. */ |
| cp = ""; |
| else |
| { |
| /* Parse the file's contents. */ |
| int c; |
| char buf1[50+1]; |
| char buf2[50+1]; |
| char *res_ptr = NULL; |
| size_t res_size = 0; |
| size_t l1, l2; |
| |
| for (;;) |
| { |
| c = getc (fp); |
| if (c == EOF) |
| break; |
| if (c == '\n' || c == ' ' || c == '\t') |
| continue; |
| if (c == '#') |
| { |
| /* Skip comment, to end of line. */ |
| do |
| c = getc (fp); |
| while (!(c == EOF || c == '\n')); |
| if (c == EOF) |
| break; |
| continue; |
| } |
| ungetc (c, fp); |
| if (fscanf(fp, "%50s %50s", buf1, buf2) < 2) |
| break; |
| l1 = strlen (buf1); |
| l2 = strlen (buf2); |
| if (res_size == 0) |
| { |
| res_size = l1 + 1 + l2 + 1; |
| res_ptr = malloc (res_size + 1); |
| } |
| else |
| { |
| res_size += l1 + 1 + l2 + 1; |
| res_ptr = realloc (res_ptr, res_size + 1); |
| } |
| if (res_ptr == NULL) |
| { |
| /* Out of memory. */ |
| res_size = 0; |
| break; |
| } |
| strcpy (res_ptr + res_size - (l2 + 1) - (l1 + 1), buf1); |
| strcpy (res_ptr + res_size - (l2 + 1), buf2); |
| } |
| fclose (fp); |
| if (res_size == 0) |
| cp = ""; |
| else |
| { |
| *(res_ptr + res_size) = '\0'; |
| cp = res_ptr; |
| } |
| } |
| |
| if (file_name != NULL) |
| free (file_name); |
| |
| #else /* WIN32 */ |
| |
| /* To avoid the troubles of installing a separate file in the same |
| directory as the DLL and of retrieving the DLL's directory at |
| runtime, simply inline the aliases here. */ |
| |
| cp = "CP936" "\0" "GBK" "\0" |
| "CP1361" "\0" "JOHAB" "\0"; |
| #endif |
| |
| charset_aliases = cp; |
| } |
| |
| return cp; |
| } |
| |
| /* Determine the current locale's character encoding, and canonicalize it |
| into one of the canonical names listed in config.charset. |
| The result must not be freed; it is statically allocated. |
| If the canonical name cannot be determined, the result is a non-canonical |
| name. */ |
| |
| #ifdef STATIC |
| STATIC |
| #endif |
| const char * |
| locale_charset () |
| { |
| const char *codeset; |
| const char *aliases; |
| |
| #ifndef WIN32 |
| |
| # if HAVE_LANGINFO_CODESET |
| |
| /* Most systems support nl_langinfo (CODESET) nowadays. */ |
| codeset = nl_langinfo (CODESET); |
| |
| # else |
| |
| /* On old systems which lack it, use setlocale or getenv. */ |
| const char *locale = NULL; |
| |
| /* But most old systems don't have a complete set of locales. Some |
| (like SunOS 4 or DJGPP) have only the C locale. Therefore we don't |
| use setlocale here; it would return "C" when it doesn't support the |
| locale name the user has set. */ |
| # if HAVE_SETLOCALE && 0 |
| locale = setlocale (LC_CTYPE, NULL); |
| # endif |
| if (locale == NULL || locale[0] == '\0') |
| { |
| locale = getenv ("LC_ALL"); |
| if (locale == NULL || locale[0] == '\0') |
| { |
| locale = getenv ("LC_CTYPE"); |
| if (locale == NULL || locale[0] == '\0') |
| locale = getenv ("LANG"); |
| } |
| } |
| |
| /* On some old systems, one used to set locale = "iso8859_1". On others, |
| you set it to "language_COUNTRY.charset". In any case, we resolve it |
| through the charset.alias file. */ |
| codeset = locale; |
| |
| # endif |
| |
| #else /* WIN32 */ |
| |
| static char buf[2 + 10 + 1]; |
| |
| /* Win32 has a function returning the locale's codepage as a number. */ |
| sprintf (buf, "CP%u", GetACP ()); |
| codeset = buf; |
| |
| #endif |
| |
| if (codeset == NULL) |
| /* The canonical name cannot be determined. */ |
| codeset = ""; |
| |
| /* Resolve alias. */ |
| for (aliases = get_charset_aliases (); |
| *aliases != '\0'; |
| aliases += strlen (aliases) + 1, aliases += strlen (aliases) + 1) |
| if (strcmp (codeset, aliases) == 0 |
| || (aliases[0] == '*' && aliases[1] == '\0')) |
| { |
| codeset = aliases + strlen (aliases) + 1; |
| break; |
| } |
| |
| return codeset; |
| } |