Andrew's git - gitweb.git/blob

   1/*
   2 * Copyright (c) 2010 Ævar Arnfjörð Bjarmason
   3 */
   4
   5#include "git-compat-util.h"
   6#include "gettext.h"
   7#include "strbuf.h"
   8#include "utf8.h"
   9
  10#ifndef NO_GETTEXT
  11#       include <locale.h>
  12#       include <libintl.h>
  13#       ifdef HAVE_LIBCHARSET_H
  14#               include <libcharset.h>
  15#       else
  16#               include <langinfo.h>
  17#               define locale_charset() nl_langinfo(CODESET)
  18#       endif
  19#endif
  20
  21#ifdef GETTEXT_POISON
  22int use_gettext_poison(void)
  23{
  24        static int poison_requested = -1;
  25        if (poison_requested == -1)
  26                poison_requested = getenv("GIT_GETTEXT_POISON") ? 1 : 0;
  27        return poison_requested;
  28}
  29#endif
  30
  31#ifndef NO_GETTEXT
  32static int test_vsnprintf(const char *fmt, ...)
  33{
  34        char buf[26];
  35        int ret;
  36        va_list ap;
  37        va_start(ap, fmt);
  38        ret = vsnprintf(buf, sizeof(buf), fmt, ap);
  39        va_end(ap);
  40        return ret;
  41}
  42
  43static const char *charset;
  44static void init_gettext_charset(const char *domain)
  45{
  46        /*
  47           This trick arranges for messages to be emitted in the user's
  48           requested encoding, but avoids setting LC_CTYPE from the
  49           environment for the whole program.
  50
  51           This primarily done to avoid a bug in vsnprintf in the GNU C
  52           Library [1]. which triggered a "your vsnprintf is broken" error
  53           on Git's own repository when inspecting v0.99.6~1 under a UTF-8
  54           locale.
  55
  56           That commit contains a ISO-8859-1 encoded author name, which
  57           the locale aware vsnprintf(3) won't interpolate in the format
  58           argument, due to mismatch between the data encoding and the
  59           locale.
  60
  61           Even if it wasn't for that bug we wouldn't want to use LC_CTYPE at
  62           this point, because it'd require auditing all the code that uses C
  63           functions whose semantics are modified by LC_CTYPE.
  64
  65           But only setting LC_MESSAGES as we do creates a problem, since
  66           we declare the encoding of our PO files[2] the gettext
  67           implementation will try to recode it to the user's locale, but
  68           without LC_CTYPE it'll emit something like this on 'git init'
  69           under the Icelandic locale:
  70
  71               Bj? til t?ma Git lind ? /hlagh/.git/
  72
  73           Gettext knows about the encoding of our PO file, but we haven't
  74           told it about the user's encoding, so all the non-US-ASCII
  75           characters get encoded to question marks.
  76
  77           But we're in luck! We can set LC_CTYPE from the environment
  78           only while we call nl_langinfo and
  79           bind_textdomain_codeset. That suffices to tell gettext what
  80           encoding it should emit in, so it'll now say:
  81
  82               Bjó til tóma Git lind í /hlagh/.git/
  83
  84           And the equivalent ISO-8859-1 string will be emitted under a
  85           ISO-8859-1 locale.
  86
  87           With this change way we get the advantages of setting LC_CTYPE
  88           (talk to the user in his language/encoding), without the major
  89           drawbacks (changed semantics for C functions we rely on).
  90
  91           However foreign functions using other message catalogs that
  92           aren't using our neat trick will still have a problem, e.g. if
  93           we have to call perror(3):
  94
  95           #include <stdio.h>
  96           #include <locale.h>
  97           #include <errno.h>
  98
  99           int main(void)
 100           {
 101                   setlocale(LC_MESSAGES, "");
 102                   setlocale(LC_CTYPE, "C");
 103                   errno = ENODEV;
 104                   perror("test");
 105                   return 0;
 106           }
 107
 108           Running that will give you a message with question marks:
 109
 110           $ LANGUAGE= LANG=de_DE.utf8 ./test
 111           test: Kein passendes Ger?t gefunden
 112
 113           The vsnprintf bug has been fixed since glibc 2.17.
 114
 115           Then we could simply set LC_CTYPE from the environment, which would
 116           make things like the external perror(3) messages work.
 117
 118           See t/t0203-gettext-setlocale-sanity.sh's "gettext.c" tests for
 119           regression tests.
 120
 121           1. http://sourceware.org/bugzilla/show_bug.cgi?id=6530
 122           2. E.g. "Content-Type: text/plain; charset=UTF-8\n" in po/is.po
 123        */
 124        setlocale(LC_CTYPE, "");
 125        charset = locale_charset();
 126        bind_textdomain_codeset(domain, charset);
 127        /* the string is taken from v0.99.6~1 */
 128        if (test_vsnprintf("%.*s", 13, "David_K\345gedal") < 0)
 129                setlocale(LC_CTYPE, "C");
 130}
 131
 132void git_setup_gettext(void)
 133{
 134        const char *podir = getenv("GIT_TEXTDOMAINDIR");
 135
 136        if (!podir)
 137                podir = GIT_LOCALE_PATH;
 138        bindtextdomain("git", podir);
 139        setlocale(LC_MESSAGES, "");
 140        init_gettext_charset("git");
 141        textdomain("git");
 142}
 143
 144/* return the number of columns of string 's' in current locale */
 145int gettext_width(const char *s)
 146{
 147        static int is_utf8 = -1;
 148        if (is_utf8 == -1)
 149                is_utf8 = !strcmp(charset, "UTF-8");
 150
 151        return is_utf8 ? utf8_strwidth(s) : strlen(s);
 152}
 153#endif