Re: [ping] [PATCH] Different outputs affected by locale

Pedro Alves
2014-06-12T17:23:46Z

On 06/12/2014 03:37 PM, Yao Qi wrote:
> On 06/12/2014 07:36 PM, Pedro Alves wrote:
>> What does "show host-charset" show on Windows, before and after
>> you make GDB pick LC_CTYPE=C from the environment (with the
>> setlocale gnulib module)?
>
> GDB on Windows gets host charset from GetACP(), in
> charset.c:_initialize_charset ().
>
> #elif defined (USE_WIN32API)
> {
> /* "CP" + x<=5 digits + paranoia. */
> static char w32_host_default_charset[16];
>
> snprintf (w32_host_default_charset, sizeof w32_host_default_charset,
> "CP%d", GetACP());
> auto_host_charset_name = w32_host_default_charset;
> auto_target_charset_name = auto_host_charset_name;
> }
> #endif
>

I note gnulib's nl_langinfo replacement actually does
the same thing.

> GetACP doesn't depend on locale,

Yeah, it's a mess, and those are really different
things. The former is the system locale, while the latter
the user locale. MSDN is confusing, but lots of blogs around
explaining this.

> so I don't think LC_CTYPE=C affects the
> host-charset in GDB. However, I do this:
>
> printf ("%d\n", GetACP());
>
> setlocale (LC_CTYPE, "");
> printf ("%d\n", GetACP());
>
> setlocale (LC_CTYPE, "C");
> printf ("%d\n", GetACP());
>
> On my Windows machine, 1252 is printed three times.

So what I'm thinking is indeed going with making the test
accept the cent, but conditioned, like:

# Fallback to assuming 7-bit ASCII. Test are ran under LC_CTYPE=C.

set cent "\\\\242"

set test "show host-charset"
gdb_test_multiple $test $test {
-re "CP1252\r\n$gdb_prompt $" {
# With Windows code page 1252 (Latin 1), the cent
# is printable.
set cent "\u00A2"
pass $test
}
-re "$gdb_prompt $" {
pass $test
}
}

>
>>
>> (Ideally, the wchar tests would actually iterate testing GDB
>> behaves as expected with different values of LC_CTYPE, etc. set
>> in the environment. With all other tests assuming ASCII as set
>> by default by the testsuite framework.)
>
> On the condition that we know or enumerate the expected output for
> wchars under each LC_CTYPE on different host (or OS). Test like this
> is out of the scope of GDB (or debugger) testing, IMO.

Not an exaustive test, and not by host, but just by picking a couple
charsets/locales. So that we at least ensure that the framework is
all in sync. That is, check:

$ unset LC_CTYPE; gdb -ex "show host-charset" -ex ' p "\u00A2"' --batch
$ LC_CTYPE=XXX gdb -ex "show host-charset" -ex ' p "\u00A2"' --batch
$ LC_CTYPE=en_US gdb -ex "show host-charset" -ex ' p "\u00A2"' --batch
$ LC_CTYPE=en_US.UTF-8 gdb -ex "show host-charset" -ex ' p "\u00A2"' --batch

--
Pedro Alves