Re: WM_GETTEXTLENGTH returns double size

[Shachar Shemesh]

I think the correct thing to do is return the output of *_tcslen*. Since 
we don't have TCHARs inside wine, this translates to using wcslen if 
wer'e a UNICODE function, or strlen if wer'e not (notice that while 
_mbslen returns the number of characters in the string, strlen returns 
the number of bytes in the string. See 
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclib/html/...).

Also, assuming you are implementing this over my GetFontLanguageInfo 
patch (the title was "Extremely preliminary BiDi patch" - not commited 
yet), you can use that function to find out whether special MBCS 
processing is necessary for the current locale. Just like I said in that 
email, I am not sure it is worth it, performance wise.

If you do decide to use my patch, notice that GetFontLanguageInfo is a 
skeleton. I did include an MBCS pattern to those languages I happened to 
know required MBCS, but as this is far from my main field of experties, 
errors are not unlikely.

Shachar

Andriy Palamarchuk wrote:
> Andriy Palamarchuk wrote:
> > This happens in code which unmaps message, mapped
>
> from
> > ASCII to Unicode.
> > See windows/winproc.c, function
> > WINPROC_UnmapMsg32ATo32W:
> >
> > case WM_GETTEXTLENGTH:
> >   case CB_GETLBTEXTLEN:
> >   case LB_GETTEXTLEN:
> >       /* there may be one DBCS char for each
>
> Unicode
> > char */
> >       return result * 2;
> >
> > What is the correct way to handle double-byte
> > characters in this situation?
>
> The best approach I could think of is to send an
> internal message from this location which returns
> lengths of Unicode and ASCII strings. This message
> will be processed only by our controls.
> If lengths of the Unicode strings are the same this
> means that both are generated by our code for the same
> text and I return the A length. If the lengths are
> different this means length was generated not in our
> code and I keep existing behavior (return double
> original Unicode length).
>
> This method looks pretty safe and gives correct
> behavior in almost all cases.
>
> Comments, suggestions?
> Andriy
>
> Do You Yahoo!?
> Yahoo! - Official partner of 2002 FIFA World Cup
> http://fifaworldcup.yahoo.com