Subject: Re: bug#10299: Emacs doesn't handle Unicode characters in keyboard layout on MS Windows

From: Lennart Borgman <[email-masked]>
Date: Mon, 19 Dec 2011 12:17:50 +0100

On Mon, Dec 19, 2011 at 12:04, Joakim Hårsman <[email-masked]> wrote:
> On 19 December 2011 11:59, Lennart Borgman <[email-masked]> wrote:
>> On Mon, Dec 19, 2011 at 11:44, Joakim Hårsman <[email-masked]> wrote:
>>> On 18 December 2011 19:13, Eli Zaretskii <[email-masked]> wrote:
>>>>> Date: Sun, 18 Dec 2011 18:31:55 +0100
>>>>> From: Joakim Hårsman <[email-masked]>
>>>>>
>>>>> > That's good news.  However, I'm puzzled: are you saying that the code
>>>>> > points passed by Windows to Emacs for the characters generated by MKLC
>>>>> > are outside the Unicode BMP, i.e. larger than 65535?  If so, what code
>>>>> > points are they?
>>>>>
>>>>> No, none of the characters I needed are outside the BMP.
>>>>>
>>>>> WM_CHAR encodes the codepoint in UTF-16 inside wParam, while
>>>>> WM_UNICHAR uses UTF-32. So if I press something which gives U+2218
>>>>> RING OPERATOR, I get a WM_CHAR event with a wParam of 2228248 or
>>>>> 0x220018.
>>>>
>>>> ??? UTF-16 encodes the characters in the BMP as themselves, i.e. a
>>>> single 16-bit value that is numerically identical to the codepoint.
>>>> That is, you should have gotten 0x2218.  What am I missing?
>>>
>>> I just assumed Windows encoded the codepoints into a DWORD in some
>>> funky way, but looking more closely at the documentattion it appears
>>> like wParam should just be the codepoint. Even more strangely, some
>>> places claim that if a keyboard produces a character outside the BMP,
>>> you get two WM_CHAR events.
>>>
>>> From what I can tell, Emacs itself never alters wParam, but I guess
>>> Windows might do some funky multibyte encoding since Emacs isn't
>>> completely Unicode?
>>
>> Maybe Emacs on windows still is using the ANSI version of DefWindowProc? See
>>
>> http://blogs.msdn.com/b/michkap/archive/2007/03/25/1945659.aspx
>
> I looked at that page as well, but it says that the ANSI DefWindowProc
> is supposed to post one or two ANSI characters, and it definitely
> isn't doing that. I get teh correct Unciode character, just spread
> over the low and high word of the wParam dword.

Strange. What is the reason Emacs is still using the ANSI version?
Maybe a mix of ANSI and UNICODE versions gives strange results?