[Qemu-devel] alt-gr on Windows

[Thebault, Remi]

Hi list!

This is not the first post on this topic, but I haven't seen any 
solution about it.
I tested so far linux guest on windows host and the AltGr key is dead in 
the guest. (using git master branch)

On french keyboard, the keys to yield the bar "|" are alt-gr + 6.
when executing this combination on keyboard, Windows generates this:
    - L-CTRL
    - R-ALT
    - 6

in Qemu (only digged gtk UI so far), pressing alt-gr + 6 generates the 
following trace
    - L-CTRL
    - L-ALT   <-- note left here
    - 6

This comes from the Win32 call MapVirtualKey in gtk.c that maps to 
scancodes without left/right distinction.
Even when sending the right alt to the guest, the alt-gr key remains 
dead because of ctrl being virtually pressed. I found out however that 
if R-ALT + 6 is sent without the ctrl key, the guest finally recognize 
it and prints the bar, @, # and other [}{].

To make things easier, Windows delivers the ctrl code before the alt 
code, so catching it cleanly before delivery to the guest is probably tough.
I could however come to an easy and quick fix with sending the "ctrl up" 
signal to the guest before the "r-alt down" is sent.

My current code do not handle all corner cases (eg: turbo mode) and only 
fixes the gtk ui, but would such fix be accepted in the repo?
Would this break somehow the windows guest on windows host?

Thanks,
Rémi