On Friday 01 June 2007 00:08, Matthew Garrett wrote: > On Thu, May 31, 2007 at 11:33:10PM -0400, Dmitry Torokhov wrote: > > On Thursday 31 May 2007 21:44, Matthew Garrett wrote: > > > It's not trivial at all. You need to introduce a mechanism for noting a > > > KEY_UNKNOWN keypress. It then needs to signal the user (dbus is probably > > > the best layer for this), but you need to ensure that you only signal > > > the user who is currently at the keyboard. This needs to be presented to > > > the user via some sort of UI, which will then need to signal some sort > > > of privileged process to actually change the keymap. > > > > Not necessarily priveleged - you most likely already change ownership > > of event devices to user who is logged at console (so your force feedback > > joysticks work). > > If you let users alter the kernel keymap, then you need to implement > support for resetting the kernel keymap on exit. Otherwise it's a > trivial DoS. >
You already do - do you let your users play games with force-feedback joysticks? To load force feedback effect you need write permissions for corresponding event device. And we are talking about console owner here - with current desktop-oriented distributions they already get access to host of otherwise restricted devices. > > > When the user logs > > > out, you'll then need to unmap the key again and repeat as necessary for > > > any new user who logs in. > > > > I think we should aim at the most common case - when there are no multiple > > users on the box. Then the utility that detects KEY_UNKNOWN just saves the > > mapping user chose and automatically reload keymap upon next reboot. > > The standard setup for home machines tends to be an account per family > member. That could be... Although it is desktops that are usually shared. Hmm, I am trying to remember setup of the people I know... I think the most common setup is a desktop in an easily accessible place (kitchen) with a single account. Older kids/parents may have their own desktop/laptops that are not shared. > The standard setup in an office environment is likely to be > multiuser. Huh? In my limited experience everyone in the office gets its own box. And I am not talking about software shop. > > > Note that KEY_UNKNOWN solution does not preculde futher customization on > > per-user base once default action is established. > > No, but it makes it significantly more confusing. User 1 chooses a > setup. This gets saved. User 2 remaps keys based on User 1's settings > (which have been restored at bootup). User 1 alters key mapping. User 2 > suddenly becomes hugely confused. One user is an administrator. He can alter the global keymap. If there are multiple users he may need to be cautious. > > > > > > Alternatively, we could generate a keycode and then let the user map > > > that to an X keysym. We've even already got code to do this. > > > > > > > There is world outside of X. > > On machines like we're discussing (laptops, basically) it's a tiny > world. Optimise for the common case, not the rare one. > > > > That's a ridiculously niche case, and can be handled in userspace. Just > > > have udev do remapping when it detects multiple keyboards that both have > > > KEY_PROG* layers, or let X have different keymaps for different input > > > devices. We shouldn't make the (by far) common case significantly more > > > difficult to deal with this one. > > > > > > > No, it is not a niche case. I think it is much more common than the case > > where > > you have multiple users for the same box using different keymaps. Even if > > box > > is shared there most likely will be one person setting it up in the > > beginning > > and the rest will follow his/her setup. > > How many users plug external keyboards with unlabelled keys into a > laptop? No, I really don't think that's a common case at all. I think quite a few people use external keyboards. I know that in my office everyone with a laptop has a docking station and uses full keyboard with it. I use external AT keyboard at home... As far as unlabeled goes - they may be labeled but we may not know their labels. > The solution that satisfies the largest number of users with the > smallest amount of work is the one where pressing a key on the keyboard > results in X events being generated. Right now, that requires that the > key generate a real keycode. > Again, it is not only about X. What if X is not running (or running but nobody is logged in)? There are number of events (SUSPEND, WLAN switch, undock request, etc) that should be handled by daemons not depending on X. -- Dmitry
