git/gettext.c
Jeff King 93f7d9108a gettext.c: move get_preferred_languages() from http.c
Calling setlocale(LC_MESSAGES, ...) directly from http.c, without
including <locale.h>, was causing compilation warnings.  Move the
helper function to gettext.c that already includes the header and
where locale-related issues are handled.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-26 14:09:20 -08:00

179 lines
4.8 KiB
C

/*
* Copyright (c) 2010 Ævar Arnfjörð Bjarmason
*/
#include "git-compat-util.h"
#include "gettext.h"
#include "strbuf.h"
#include "utf8.h"
#ifndef NO_GETTEXT
# include <locale.h>
# include <libintl.h>
# ifdef HAVE_LIBCHARSET_H
# include <libcharset.h>
# else
# include <langinfo.h>
# define locale_charset() nl_langinfo(CODESET)
# endif
#endif
/*
* Guess the user's preferred languages from the value in LANGUAGE environment
* variable and LC_MESSAGES locale category if NO_GETTEXT is not defined.
*
* The result can be a colon-separated list like "ko:ja:en".
*/
const char *get_preferred_languages(void)
{
const char *retval;
retval = getenv("LANGUAGE");
if (retval && *retval)
return retval;
#ifndef NO_GETTEXT
retval = setlocale(LC_MESSAGES, NULL);
if (retval && *retval &&
strcmp(retval, "C") &&
strcmp(retval, "POSIX"))
return retval;
#endif
return NULL;
}
#ifdef GETTEXT_POISON
int use_gettext_poison(void)
{
static int poison_requested = -1;
if (poison_requested == -1)
poison_requested = getenv("GIT_GETTEXT_POISON") ? 1 : 0;
return poison_requested;
}
#endif
#ifndef NO_GETTEXT
static int test_vsnprintf(const char *fmt, ...)
{
char buf[26];
int ret;
va_list ap;
va_start(ap, fmt);
ret = vsnprintf(buf, sizeof(buf), fmt, ap);
va_end(ap);
return ret;
}
static const char *charset;
static void init_gettext_charset(const char *domain)
{
/*
This trick arranges for messages to be emitted in the user's
requested encoding, but avoids setting LC_CTYPE from the
environment for the whole program.
This primarily done to avoid a bug in vsnprintf in the GNU C
Library [1]. which triggered a "your vsnprintf is broken" error
on Git's own repository when inspecting v0.99.6~1 under a UTF-8
locale.
That commit contains a ISO-8859-1 encoded author name, which
the locale aware vsnprintf(3) won't interpolate in the format
argument, due to mismatch between the data encoding and the
locale.
Even if it wasn't for that bug we wouldn't want to use LC_CTYPE at
this point, because it'd require auditing all the code that uses C
functions whose semantics are modified by LC_CTYPE.
But only setting LC_MESSAGES as we do creates a problem, since
we declare the encoding of our PO files[2] the gettext
implementation will try to recode it to the user's locale, but
without LC_CTYPE it'll emit something like this on 'git init'
under the Icelandic locale:
Bj? til t?ma Git lind ? /hlagh/.git/
Gettext knows about the encoding of our PO file, but we haven't
told it about the user's encoding, so all the non-US-ASCII
characters get encoded to question marks.
But we're in luck! We can set LC_CTYPE from the environment
only while we call nl_langinfo and
bind_textdomain_codeset. That suffices to tell gettext what
encoding it should emit in, so it'll now say:
Bjó til tóma Git lind í /hlagh/.git/
And the equivalent ISO-8859-1 string will be emitted under a
ISO-8859-1 locale.
With this change way we get the advantages of setting LC_CTYPE
(talk to the user in his language/encoding), without the major
drawbacks (changed semantics for C functions we rely on).
However foreign functions using other message catalogs that
aren't using our neat trick will still have a problem, e.g. if
we have to call perror(3):
#include <stdio.h>
#include <locale.h>
#include <errno.h>
int main(void)
{
setlocale(LC_MESSAGES, "");
setlocale(LC_CTYPE, "C");
errno = ENODEV;
perror("test");
return 0;
}
Running that will give you a message with question marks:
$ LANGUAGE= LANG=de_DE.utf8 ./test
test: Kein passendes Ger?t gefunden
The vsnprintf bug has been fixed since glibc 2.17.
Then we could simply set LC_CTYPE from the environment, which would
make things like the external perror(3) messages work.
See t/t0203-gettext-setlocale-sanity.sh's "gettext.c" tests for
regression tests.
1. http://sourceware.org/bugzilla/show_bug.cgi?id=6530
2. E.g. "Content-Type: text/plain; charset=UTF-8\n" in po/is.po
*/
setlocale(LC_CTYPE, "");
charset = locale_charset();
bind_textdomain_codeset(domain, charset);
/* the string is taken from v0.99.6~1 */
if (test_vsnprintf("%.*s", 13, "David_K\345gedal") < 0)
setlocale(LC_CTYPE, "C");
}
void git_setup_gettext(void)
{
const char *podir = getenv("GIT_TEXTDOMAINDIR");
if (!podir)
podir = GIT_LOCALE_PATH;
bindtextdomain("git", podir);
setlocale(LC_MESSAGES, "");
init_gettext_charset("git");
textdomain("git");
}
/* return the number of columns of string 's' in current locale */
int gettext_width(const char *s)
{
static int is_utf8 = -1;
if (is_utf8 == -1)
is_utf8 = !strcmp(charset, "UTF-8");
return is_utf8 ? utf8_strwidth(s) : strlen(s);
}
#endif