Re: cairo and character encoding issues

[<tim...@lp...>]

Allin Cottrell a écrit :
> On Sat, 24 Nov 2007, Ethan A Merritt wrote:
>
>   
>>> 2) How did LC_CTYPE _get_ to be equal to en_US.UTF-8 at this point 
>>> in execution, when the only command that has been issued is "show 
>>> locale"? 
>>>       
>> Puzzling indeed.  With the help of many trace statements, I find that
>> the locale is loaded during the first call to readline_ipc() in rlgets(),
>> which is itself called from gp_get_string()...
>>     
>
> Nice detective work!
>
>   
Please note that gtk+ (used by wxGTK, used by wxt) is another offender 
here which calls setlocale(LC_ALL,"") or something like that. For 
example, on my system where wxt is built:

> tipote@tipote-laptop:~$ echo "show locale; plot x; show locale" | gnuplot
>
>         LC_CTYPE is C
>         LC_TIME is C
>
>
>         LC_CTYPE is fr_FR.UTF-8
>         LC_TIME is fr_FR.UTF-8

When wxt is initialized, gtk+ loads the locale settings. I have already 
had to work around it for LC_NUMERIC in wxt, as you can see from the 
following lines of code taken from lines 1445-1449 in 
src/wxterminal/wxt_gui.cpp:

> #ifdef HAVE_LOCALE_H
>         /* when wxGTK is initialised, GTK+ also sets the locale of the 
> program itself;
>          * we must revert it */
>         setlocale(LC_NUMERIC, "C");
> #endif /*have_locale_h*/


At least, we know understand what happens on Mojca's box too:
>
> Here I have:
>
>   
>> > locale
>>     
> LANG=
> LC_COLLATE="sl_SI.UTF-8"
> LC_CTYPE="sl_SI.UTF-8"
> LC_MESSAGES="sl_SI.UTF-8"
> LC_MONETARY="sl_SI.UTF-8"
> LC_NUMERIC="sl_SI.UTF-8"
> LC_TIME="sl_SI.UTF-8"
> LC_ALL="sl_SI.UTF-8"
> Terminal type set to 'aqua'
> gnuplot> show locale
>
>         LC_CTYPE is C
>         LC_TIME is C
>         LC_NUMERIC is C
>
> gnuplot>
>
> Mojca

Mojca runs MacOS, so she surely doesn't have wxt, aqua is indeed the 
terminal initialized on startup, and she most likely doesn't have 
readline. That's why her LC_* are not set from her locale settings.


>>> 3) Anyway, by the time you plot a graph using cairo the LC_CTYPE 
>>> setting has reverted to "C".  I've verified that by sticking a 
>>> print before the g_get_charset() invocation:
>>>       
>> I can't reproduce that. Once the locale gets set, it sticks.  
>> As you would expect.
>>     
>
> Yup, I was wrong.  The active factor was interactive vs 
> non-interactive, not anything that happened in between "show 
> locale" and gp_cairo calling g_get_charset.
>   
Ah, I was puzzled too by that one.

>   
>> I am thinking that regardless of any possible bugs in the cairo 
>> processing, we should be consistent and always call 
>> setlocale(LC_CTYPE,"").
>>     
>
> That makes sense to me: maybe in init_locale?
>   
I agree with that. Why not LC_ALL by the way ?

Timothée