Re: [PATCH] Input: hyperv-keyboard - implement Type Clipboard Text

From: Dmitry Torokhov
Date: Fri Aug 15 2014 - 12:57:45 EST

Hi Dexuan,

On Fri, Aug 15, 2014 at 02:41:59AM -0700, Dexuan Cui wrote:
> In the menu of the Hyper-V's Virtual Machine Connection, there is a feature
> called "Clipboard | Type clipboard text", which can be used to copy a string
> in the host's clipboard into the guest's current input focus(text console or
> a GUI window).
> Currently the feature doesn't work for Linux VM because the driver
> hyperv-keyboard hasn't been enhanced to support it -- this patch is made
> to do it.
> For each char in the string, the host sends 2 events (key down/up with the
> char's UNICODE value) to the guest.
> The patch finds each char's scan codes of key down/up, and injects the
> scan codes to the serio keyboard module.
> Known issues:
> 1) Only printable ASCII chars are supported, and unsupported chars are
> ignored. It seems unlikely to support generic UNICODE chars because there
> is not a generic API to inject a UNICODE char to text mode console, KDE,
> gnome, etc.
> 2) When we use the feature, make sure the CapsLock state of the VM's
> (virtual) keyboard is OFF because this patch assumes it -- we'll try to
> fix this later, probably by tracking the state of virtual CapsLock, because
> it looks the keyboard module doesn't supply an API for us to query the state
> of the keyboard.
> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx>

No way. If you want to do this this way, do it in hypervisor code and keep
feeding AT scan codes to hyperv-keyboard, although I am pretty sure users of
French, Czech and other keyboard layouts with numbers in upper register and
symbols in lower will have a few choice words for you.

If you want real cut-and-paste support in various DEs I'd recommend working
with VMware on open-vm-tools package to see what can be shared/reused there.

Consider this NACked with prejudice.


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