git/gettext.h
Ævar Arnfjörð Bjarmason 6cdccfce1e i18n: make GETTEXT_POISON a runtime option
Change the GETTEXT_POISON compile-time + runtime GIT_GETTEXT_POISON
test parameter to only be a GIT_TEST_GETTEXT_POISON=<non-empty?>
runtime parameter, to be consistent with other parameters documented
in "Running tests with special setups" in t/README.

When I added GETTEXT_POISON in bb946bba76 ("i18n: add GETTEXT_POISON
to simulate unfriendly translator", 2011-02-22) I was concerned with
ensuring that the _() function would get constant folded if NO_GETTEXT
was defined, and likewise that GETTEXT_POISON would be compiled out
unless it was defined.

But as the benchmark in my [1] shows doing a one-off runtime
getenv("GIT_TEST_[...]") is trivial, and since GETTEXT_POISON was
originally added the GIT_TEST_* env variables have become the common
idiom for turning on special test setups.

So change GETTEXT_POISON to work the same way. Now the
GETTEXT_POISON=YesPlease compile-time option is gone, and running the
tests with GIT_TEST_GETTEXT_POISON=[YesPlease|] can be toggled on/off
without recompiling.

This allows for conditionally amending tests to test with/without
poison, similar to what 859fdc0c3c ("commit-graph: define
GIT_TEST_COMMIT_GRAPH", 2018-08-29) did for GIT_TEST_COMMIT_GRAPH. Do
some of that, now we e.g. always run the t0205-gettext-poison.sh test.

I did enough there to remove the GETTEXT_POISON prerequisite, but its
inverse C_LOCALE_OUTPUT is still around, and surely some tests using
it can be converted to e.g. always set GIT_TEST_GETTEXT_POISON=.

Notes on the implementation:

 * We still compile a dedicated GETTEXT_POISON build in Travis
   CI. Perhaps this should be revisited and integrated into the
   "linux-gcc" build, see ae59a4e44f ("travis: run tests with
   GIT_TEST_SPLIT_INDEX", 2018-01-07) for prior art in that area. Then
   again maybe not, see [2].

 * We now skip a test in t0000-basic.sh under
   GIT_TEST_GETTEXT_POISON=YesPlease that wasn't skipped before. This
   test relies on C locale output, but due to an edge case in how the
   previous implementation of GETTEXT_POISON worked (reading it from
   GIT-BUILD-OPTIONS) wasn't enabling poison correctly. Now it does,
   and needs to be skipped.

 * The getenv() function is not reentrant, so out of paranoia about
   code of the form:

       printf(_("%s"), getenv("some-env"));

   call use_gettext_poison() in our early setup in git_setup_gettext()
   so we populate the "poison_requested" variable in a codepath that's
   won't suffer from that race condition.

 * We error out in the Makefile if you're still saying
   GETTEXT_POISON=YesPlease to prompt users to change their
   invocation.

 * We should not print out poisoned messages during the test
   initialization itself to keep it more readable, so the test library
   hides the variable if set in $GIT_TEST_GETTEXT_POISON_ORIG during
   setup. See [3].

See also [4] for more on the motivation behind this patch, and the
history of the GETTEXT_POISON facility.

1. https://public-inbox.org/git/871s8gd32p.fsf@evledraar.gmail.com/
2. https://public-inbox.org/git/20181102163725.GY30222@szeder.dev/
3. https://public-inbox.org/git/20181022202241.18629-2-szeder.dev@gmail.com/
4. https://public-inbox.org/git/878t2pd6yu.fsf@evledraar.gmail.com/

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2018-11-09 11:25:19 +09:00

93 lines
2.2 KiB
C

/*
* Copyright (c) 2010-2011 Ævar Arnfjörð Bjarmason
*
* This is a skeleton no-op implementation of gettext for Git.
* You can replace it with something that uses libintl.h and wraps
* gettext() to try out the translations.
*/
#ifndef GETTEXT_H
#define GETTEXT_H
#if defined(_) || defined(Q_)
#error "namespace conflict: '_' or 'Q_' is pre-defined?"
#endif
#ifndef NO_GETTEXT
# include <libintl.h>
#else
# ifdef gettext
# undef gettext
# endif
# define gettext(s) (s)
# ifdef ngettext
# undef ngettext
# endif
# define ngettext(s, p, n) ((n == 1) ? (s) : (p))
#endif
#define FORMAT_PRESERVING(n) __attribute__((format_arg(n)))
extern int use_gettext_poison(void);
#ifndef NO_GETTEXT
extern void git_setup_gettext(void);
extern int gettext_width(const char *s);
#else
static inline void git_setup_gettext(void)
{
use_gettext_poison(); /* getenv() reentrancy paranoia */
}
static inline int gettext_width(const char *s)
{
return strlen(s);
}
#endif
static inline FORMAT_PRESERVING(1) const char *_(const char *msgid)
{
if (!*msgid)
return "";
return use_gettext_poison() ? "# GETTEXT POISON #" : gettext(msgid);
}
static inline FORMAT_PRESERVING(1) FORMAT_PRESERVING(2)
const char *Q_(const char *msgid, const char *plu, unsigned long n)
{
if (use_gettext_poison())
return "# GETTEXT POISON #";
return ngettext(msgid, plu, n);
}
/* Mark msgid for translation but do not translate it. */
#if !USE_PARENS_AROUND_GETTEXT_N
#define N_(msgid) msgid
#else
/*
* Strictly speaking, this will lead to invalid C when
* used this way:
* static const char s[] = N_("FOO");
* which will expand to
* static const char s[] = ("FOO");
* and in valid C, the initializer on the right hand side must
* be without the parentheses. But many compilers do accept it
* as a language extension and it will allow us to catch mistakes
* like:
* static const char *msgs[] = {
* N_("one")
* N_("two"),
* N_("three"),
* NULL
* };
* (notice the missing comma on one of the lines) by forcing
* a compilation error, because parenthesised ("one") ("two")
* will not get silently turned into ("onetwo").
*/
#define N_(msgid) (msgid)
#endif
const char *get_preferred_languages(void);
extern int is_utf8_locale(void);
#endif