/* Determine a canonical name for the current locale's character encoding.
Copyright (C) 2000-2006, 2008-2017 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3, 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 General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, see <http://www.gnu.org/licenses/>. */
/* Written by Bruno Haible <bruno@clisp.org>. */
#include <config.h>
/* Specification. */
#include "localcharset.h"
#include <fcntl.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#if defined __APPLE__ && defined __MACH__ && HAVE_LANGINFO_CODESET
# define DARWIN7 /* Darwin 7 or newer, i.e. Mac OS X 10.3 or newer */
#endif
#if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__
# define WINDOWS_NATIVE
# include <locale.h>
#endif
#if defined __EMX__
/* Assume EMX program runs on OS/2, even if compiled under DOS. */
# ifndef OS2
# define OS2
# endif
#endif
#if !defined WINDOWS_NATIVE
# include <unistd.h>
# if HAVE_LANGINFO_CODESET
# include <langinfo.h>
# else
# if 0 /* see comment below */
# include <locale.h>
# endif
# endif
# ifdef __CYGWIN__
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
# endif
#elif defined WINDOWS_NATIVE
# define WIN32_LEAN_AND_MEAN
# include <windows.h>
#endif
#if defined OS2
# define INCL_DOS
# include <os2.h>
#endif
/* For MB_CUR_MAX_L */
#if defined DARWIN7
# include <xlocale.h>
#endif
#if ENABLE_RELOCATABLE
# include "relocatable.h"
#else
# define relocate(pathname) (pathname)
# define relocate2(pathname,allocatedp) (*(allocatedp) = NULL, (pathname))
#endif
/* Get LIBDIR. */
#ifndef LIBDIR
# include "configmake.h"
#endif
/* Define O_NOFOLLOW to 0 on platforms where it does not exist. */
#ifndef O_NOFOLLOW
# define O_NOFOLLOW 0
#endif
#if defined _WIN32 || defined __WIN32__ || defined __CYGWIN__ || defined __EMX__ || defined __DJGPP__
/* Native Windows, Cygwin, OS/2, DOS */
# define ISSLASH(C) ((C) == '/' || (C) == '\\')
#endif
#ifndef DIRECTORY_SEPARATOR
# define DIRECTORY_SEPARATOR '/'
#endif
#ifndef ISSLASH
# define ISSLASH(C) ((C) == DIRECTORY_SEPARATOR)
#endif
#if HAVE_DECL_GETC_UNLOCKED
# undef getc
# define getc getc_unlocked
#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 (void)
{
const char *cp;
cp = charset_aliases;
if (cp == NULL)
{
#if !(defined DARWIN7 || defined VMS || defined WINDOWS_NATIVE || defined __CYGWIN__ || defined OS2)
char *malloc_dir = NULL;
const char *dir;
const char *base = "charset.alias";
char *file_name;
/* Make it possible to override the charset.alias location. This is
necessary for running the testsuite before "make install". */
dir = getenv ("CHARSETALIASDIR");
if (dir == NULL || dir[0] == '\0')
dir = relocate2 (LIBDIR, &malloc_dir);
/* 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);
}
}
free (malloc_dir);
if (file_name == NULL)
/* Out of memory. Treat the file as empty. */
cp = "";
else
{
int fd;
/* Open the file. Reject symbolic links on platforms that support
O_NOFOLLOW. This is a security feature. Without it, an attacker
could retrieve parts of the contents (namely, the tail of the
first line that starts with "* ") of an arbitrary file by placing
a symbolic link to that file under the name "charset.alias" in
some writable directory and defining the environment variable
CHARSETALIASDIR to point to that directory. */
fd = open (file_name,
O_RDONLY | (HAVE_WORKING_O_NOFOLLOW ? O_NOFOLLOW : 0));
if (fd < 0)
/* File not found. Treat it as empty. */
cp = "";
else
{
FILE *fp;
fp = fdopen (fd, "r");
if (fp == NULL)
{
/* Out of memory. Treat the file as empty. */
close (fd);
cp = "";
}
else
{
/* Parse the file's contents. */
char *res_ptr = NULL;
size_t res_size = 0;
for (;;)
{
int c;
char buf1[50+1];
char buf2[50+1];
size_t l1, l2;
char *old_res_ptr;
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);
old_res_ptr = res_ptr;
if (res_size == 0)
{
res_size = l1 + 1 + l2 + 1;
res_ptr = (char *) malloc (res_size + 1);
}
else
{
res_size += l1 + 1 + l2 + 1;
res_ptr = (char *) realloc (res_ptr, res_size + 1);
}
if (res_ptr == NULL)
{
/* Out of memory. */
res_size = 0;
free (old_res_ptr);
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;
}
}
}
free (file_name);
}
#else
# if defined DARWIN7
/* To avoid the trouble of installing a file that is shared by many
GNU packages -- many packaging systems have problems with this --,
simply inline the aliases here. */
cp = "ISO8859-1" "\0" "ISO-8859-1" "\0"
"ISO8859-2" "\0" "ISO-8859-2" "\0"
"ISO8859-4" "\0" "ISO-8859-4" "\0"
"ISO8859-5" "\0" "ISO-8859-5" "\0"
"ISO8859-7" "\0" "ISO-8859-7" "\0"
"ISO8859-9" "\0" "ISO-8859-9" "\0"
"ISO8859-13" "\0" "ISO-8859-13" "\0"
"ISO8859-15" "\0" "ISO-8859-15" "\0"
"KOI8-R" "\0" "KOI8-R" "\0"
"KOI8-U" "\0" "KOI8-U" "\0"
"CP866" "\0" "CP866" "\0"
"CP949" "\0" "CP949" "\0"
"CP1131" "\0" "CP1131" "\0"
"CP1251" "\0" "CP1251" "\0"
"eucCN" "\0" "GB2312" "\0"
"GB2312" "\0" "GB2312" "\0"
"eucJP" "\0" "EUC-JP" "\0"
"eucKR" "\0" "EUC-KR" "\0"
"Big5" "\0" "BIG5" "\0"
"Big5HKSCS" "\0" "BIG5-HKSCS" "\0"
"GBK" "\0" "GBK" "\0"
"GB18030" "\0" "GB18030" "\0"
"SJIS" "\0" "SHIFT_JIS" "\0"
"ARMSCII-8" "\0" "ARMSCII-8" "\0"
"PT154" "\0" "PT154" "\0"
/*"ISCII-DEV" "\0" "?" "\0"*/
"*" "\0" "UTF-8" "\0";
# endif
# if defined VMS
/* To avoid the troubles of an extra file charset.alias_vms in the
sources of many GNU packages, simply inline the aliases here. */
/* The list of encodings is taken from the OpenVMS 7.3-1 documentation
"Compaq C Run-Time Library Reference Manual for OpenVMS systems"
section 10.7 "Handling Different Character Sets". */
cp = "ISO8859-1" "\0" "ISO-8859-1" "\0"
"ISO8859-2" "\0" "ISO-8859-2" "\0"
"ISO8859-5" "\0" "ISO-8859-5" "\0"
"ISO8859-7" "\0" "ISO-8859-7" "\0"
"ISO8859-8" "\0" "ISO-8859-8" "\0"
"ISO8859-9" "\0" "ISO-8859-9" "\0"
/* Japanese */
"eucJP" "\0" "EUC-JP" "\0"
"SJIS" "\0" "SHIFT_JIS" "\0"
"DECKANJI" "\0" "DEC-KANJI" "\0"
"SDECKANJI" "\0" "EUC-JP" "\0"
/* Chinese */
"eucTW" "\0" "EUC-TW" "\0"
"DECHANYU" "\0" "DEC-HANYU" "\0"
"DECHANZI" "\0" "GB2312" "\0"
/* Korean */
"DECKOREAN" "\0" "EUC-KR" "\0";
# endif
# if defined WINDOWS_NATIVE || defined __CYGWIN__
/* 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"
"CP20127" "\0" "ASCII" "\0"
"CP20866" "\0" "KOI8-R" "\0"
"CP20936" "\0" "GB2312" "\0"
"CP21866" "\0" "KOI8-RU" "\0"
"CP28591" "\0" "ISO-8859-1" "\0"
"CP28592" "\0" "ISO-8859-2" "\0"
"CP28593" "\0" "ISO-8859-3" "\0"
"CP28594" "\0" "ISO-8859-4" "\0"
"CP28595" "\0" "ISO-8859-5" "\0"
"CP28596" "\0" "ISO-8859-6" "\0"
"CP28597" "\0" "ISO-8859-7" "\0"
"CP28598" "\0" "ISO-8859-8" "\0"
"CP28599" "\0" "ISO-8859-9" "\0"
"CP28605" "\0" "ISO-8859-15" "\0"
"CP38598" "\0" "ISO-8859-8" "\0"
"CP51932" "\0" "EUC-JP" "\0"
"CP51936" "\0" "GB2312" "\0"
"CP51949" "\0" "EUC-KR" "\0"
"CP51950" "\0" "EUC-TW" "\0"
"CP54936" "\0" "GB18030" "\0"
"CP65001" "\0" "UTF-8" "\0";
# endif
# if defined OS2
/* 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. */
/* The list of encodings is taken from "List of OS/2 Codepages"
by Alex Taylor:
<http://altsan.org/os2/toolkits/uls/index.html#codepages>.
See also "IBM Globalization - Code page identifiers":
<http://www-01.ibm.com/software/globalization/cp/cp_cpgid.html>. */
cp = "CP813" "\0" "ISO-8859-7" "\0"
"CP878" "\0" "KOI8-R" "\0"
"CP819" "\0" "ISO-8859-1" "\0"
"CP912" "\0" "ISO-8859-2" "\0"
"CP913" "\0" "ISO-8859-3" "\0"
"CP914" "\0" "ISO-8859-4" "\0"
"CP915" "\0" "ISO-8859-5" "\0"
"CP916" "\0" "ISO-8859-8" "\0"
"CP920" "\0" "ISO-8859-9" "\0"
"CP921" "\0" "ISO-8859-13" "\0"
"CP923" "\0" "ISO-8859-15" "\0"
"CP954" "\0" "EUC-JP" "\0"
"CP964" "\0" "EUC-TW" "\0"
"CP970" "\0" "EUC-KR" "\0"
"CP1089" "\0" "ISO-8859-6" "\0"
"CP1208" "\0" "UTF-8" "\0"
"CP1381" "\0" "GB2312" "\0"
"CP1386" "\0" "GBK" "\0"
"CP3372" "\0" "EUC-JP" "\0";
# endif
#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 (void)
{
const char *codeset;
const char *aliases;
#if !(defined WINDOWS_NATIVE || defined OS2)
# if HAVE_LANGINFO_CODESET
/* Most systems support nl_langinfo (CODESET) nowadays. */
codeset = nl_langinfo (CODESET);
# ifdef __CYGWIN__
/* Cygwin < 1.7 does not have locales. nl_langinfo (CODESET) always
returns "US-ASCII". Return the suffix of the locale name from the
environment variables (if present) or the codepage as a number. */
if (codeset != NULL && strcmp (codeset, "US-ASCII") == 0)
{
const char *locale;
static char buf[2 + 10 + 1];
locale = getenv ("LC_ALL");
if (locale == NULL || locale[0] == '\0')
{
locale = getenv ("LC_CTYPE");
if (locale == NULL || locale[0] == '\0')
locale = getenv ("LANG");
}
if (locale != NULL && locale[0] != '\0')
{
/* If the locale name contains an encoding after the dot, return
it. */
const char *dot = strchr (locale, '.');
if (dot != NULL)
{
const char *modifier;
dot++;
/* Look for the possible @... trailer and remove it, if any. */
modifier = strchr (dot, '@');
if (modifier == NULL)
return dot;
if (modifier - dot < sizeof (buf))
{
memcpy (buf, dot, modifier - dot);
buf [modifier - dot] = '\0';
return buf;
}
}
}
/* The Windows API has a function returning the locale's codepage as a
number: GetACP(). This encoding is used by Cygwin, unless the user
has set the environment variable CYGWIN=codepage:oem (which very few
people do).
Output directed to console windows needs to be converted (to
GetOEMCP() if the console is using a raster font, or to
GetConsoleOutputCP() if it is using a TrueType font). Cygwin does
this conversion transparently (see winsup/cygwin/fhandler_console.cc),
converting to GetConsoleOutputCP(). This leads to correct results,
except when SetConsoleOutputCP has been called and a raster font is
in use. */
sprintf (buf, "CP%u", GetACP ());
codeset = buf;
}
# endif
# 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 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
#elif defined WINDOWS_NATIVE
static char buf[2 + 10 + 1];
/* The Windows API has a function returning the locale's codepage as
a number, but the value doesn't change according to what the
'setlocale' call specified. So we use it as a last resort, in
case the string returned by 'setlocale' doesn't specify the
codepage. */
char *current_locale = setlocale (LC_ALL, NULL);
char *pdot;
/* If they set different locales for different categories,
'setlocale' will return a semi-colon separated list of locale
values. To make sure we use the correct one, we choose LC_CTYPE. */
if (strchr (current_locale, ';'))
current_locale = setlocale (LC_CTYPE, NULL);
pdot = strrchr (current_locale, '.');
if (pdot && 2 + strlen (pdot + 1) + 1 <= sizeof (buf))
sprintf (buf, "CP%s", pdot + 1);
else
{
/* The Windows API has a function returning the locale's codepage as a
number: GetACP().
When the output goes to a console window, it needs to be provided in
GetOEMCP() encoding if the console is using a raster font, or in
GetConsoleOutputCP() encoding if it is using a TrueType font.
But in GUI programs and for output sent to files and pipes, GetACP()
encoding is the best bet. */
sprintf (buf, "CP%u", GetACP ());
}
codeset = buf;
#elif defined OS2
const char *locale;
static char buf[2 + 10 + 1];
ULONG cp[3];
ULONG cplen;
codeset = NULL;
/* Allow user to override the codeset, as set in the operating system,
with standard language environment variables. */
locale = getenv ("LC_ALL");
if (locale == NULL || locale[0] == '\0')
{
locale = getenv ("LC_CTYPE");
if (locale == NULL || locale[0] == '\0')
locale = getenv ("LANG");
}
if (locale != NULL && locale[0] != '\0')
{
/* If the locale name contains an encoding after the dot, return it. */
const char *dot = strchr (locale, '.');
if (dot != NULL)
{
const char *modifier;
dot++;
/* Look for the possible @... trailer and remove it, if any. */
modifier = strchr (dot, '@');
if (modifier == NULL)
return dot;
if (modifier - dot < sizeof (buf))
{
memcpy (buf, dot, modifier - dot);
buf [modifier - dot] = '\0';
return buf;
}
}
/* For the POSIX locale, don't use the system's codepage. */
if (strcmp (locale, "C") == 0 || strcmp (locale, "POSIX") == 0)
codeset = "";
}
if (codeset == NULL)
{
/* OS/2 has a function returning the locale's codepage as a number. */
if (DosQueryCp (sizeof (cp), cp, &cplen))
codeset = "";
else
{
sprintf (buf, "CP%u", cp[0]);
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;
}
/* Don't return an empty string. GNU libc and GNU libiconv interpret
the empty string as denoting "the locale's character encoding",
thus GNU libiconv would call this function a second time. */
if (codeset[0] == '\0')
codeset = "ASCII";
#ifdef DARWIN7
/* Mac OS X sets MB_CUR_MAX to 1 when LC_ALL=C, and "UTF-8"
(the default codeset) does not work when MB_CUR_MAX is 1. */
if (strcmp (codeset, "UTF-8") == 0 && MB_CUR_MAX_L (uselocale (NULL)) <= 1)
codeset = "ASCII";
#endif
return codeset;
}