2 * Copyright (c) 2010 Ævar Arnfjörð Bjarmason
15 # ifdef HAVE_LIBCHARSET_H
16 # include <libcharset.h>
18 # include <langinfo.h>
19 # define locale_charset() nl_langinfo(CODESET)
23 static const char *charset;
26 * Guess the user's preferred languages from the value in LANGUAGE environment
27 * variable and LC_MESSAGES locale category if NO_GETTEXT is not defined.
29 * The result can be a colon-separated list like "ko:ja:en".
31 const char *get_preferred_languages(void)
35 retval = getenv("LANGUAGE");
36 if (retval && *retval)
40 retval = setlocale(LC_MESSAGES, NULL);
41 if (retval && *retval &&
42 strcmp(retval, "C") &&
43 strcmp(retval, "POSIX"))
50 int use_gettext_poison(void)
52 static int poison_requested = -1;
53 if (poison_requested == -1)
54 poison_requested = git_env_bool("GIT_TEST_GETTEXT_POISON", 0);
55 return poison_requested;
59 static int test_vsnprintf(const char *fmt, ...)
65 ret = vsnprintf(buf, sizeof(buf), fmt, ap);
70 static void init_gettext_charset(const char *domain)
73 This trick arranges for messages to be emitted in the user's
74 requested encoding, but avoids setting LC_CTYPE from the
75 environment for the whole program.
77 This primarily done to avoid a bug in vsnprintf in the GNU C
78 Library [1]. which triggered a "your vsnprintf is broken" error
79 on Git's own repository when inspecting v0.99.6~1 under a UTF-8
82 That commit contains a ISO-8859-1 encoded author name, which
83 the locale aware vsnprintf(3) won't interpolate in the format
84 argument, due to mismatch between the data encoding and the
87 Even if it wasn't for that bug we wouldn't want to use LC_CTYPE at
88 this point, because it'd require auditing all the code that uses C
89 functions whose semantics are modified by LC_CTYPE.
91 But only setting LC_MESSAGES as we do creates a problem, since
92 we declare the encoding of our PO files[2] the gettext
93 implementation will try to recode it to the user's locale, but
94 without LC_CTYPE it'll emit something like this on 'git init'
95 under the Icelandic locale:
97 Bj? til t?ma Git lind ? /hlagh/.git/
99 Gettext knows about the encoding of our PO file, but we haven't
100 told it about the user's encoding, so all the non-US-ASCII
101 characters get encoded to question marks.
103 But we're in luck! We can set LC_CTYPE from the environment
104 only while we call nl_langinfo and
105 bind_textdomain_codeset. That suffices to tell gettext what
106 encoding it should emit in, so it'll now say:
108 Bjó til tóma Git lind í /hlagh/.git/
110 And the equivalent ISO-8859-1 string will be emitted under a
113 With this change way we get the advantages of setting LC_CTYPE
114 (talk to the user in his language/encoding), without the major
115 drawbacks (changed semantics for C functions we rely on).
117 However foreign functions using other message catalogs that
118 aren't using our neat trick will still have a problem, e.g. if
119 we have to call perror(3):
127 setlocale(LC_MESSAGES, "");
128 setlocale(LC_CTYPE, "C");
134 Running that will give you a message with question marks:
136 $ LANGUAGE= LANG=de_DE.utf8 ./test
137 test: Kein passendes Ger?t gefunden
139 The vsnprintf bug has been fixed since glibc 2.17.
141 Then we could simply set LC_CTYPE from the environment, which would
142 make things like the external perror(3) messages work.
144 See t/t0203-gettext-setlocale-sanity.sh's "gettext.c" tests for
147 1. http://sourceware.org/bugzilla/show_bug.cgi?id=6530
148 2. E.g. "Content-Type: text/plain; charset=UTF-8\n" in po/is.po
150 setlocale(LC_CTYPE, "");
151 charset = locale_charset();
152 bind_textdomain_codeset(domain, charset);
153 /* the string is taken from v0.99.6~1 */
154 if (test_vsnprintf("%.*s", 13, "David_K\345gedal") < 0)
155 setlocale(LC_CTYPE, "C");
158 void git_setup_gettext(void)
160 const char *podir = getenv(GIT_TEXT_DOMAIN_DIR_ENVIRONMENT);
164 podir = p = system_path(GIT_LOCALE_PATH);
166 use_gettext_poison(); /* getenv() reentrancy paranoia */
168 if (!is_directory(podir)) {
173 bindtextdomain("git", podir);
174 setlocale(LC_MESSAGES, "");
175 setlocale(LC_TIME, "");
176 init_gettext_charset("git");
182 /* return the number of columns of string 's' in current locale */
183 int gettext_width(const char *s)
185 static int is_utf8 = -1;
187 is_utf8 = is_utf8_locale();
189 return is_utf8 ? utf8_strwidth(s) : strlen(s);
193 int is_utf8_locale(void)
197 const char *env = getenv("LC_ALL");
199 env = getenv("LC_CTYPE");
201 env = getenv("LANG");
204 if (strchr(env, '.'))
205 env = strchr(env, '.') + 1;
206 charset = xstrdup(env);
209 return is_encoding_utf8(charset);