On Fri, 2010-01-22 at 06:42 -0600, Brian Cameron wrote: > Jeff: > > > I summarized the steps about how screensaver works. Because a user can > > disable VT, > > also because VT has not been supported on some platforms yet, for example > > SUN Sparc, > > we will handle both situations separately. > > Yes, we need to support both VT and non-VT environments. When users log > into XDMCP sessions, for example, they also will not have access to > VT. > > > 1. After the user logs in, the user's gnome-screensaver (user session) > > process will > > start. > > > > 2. When gnome-session tells that the session is idle, > > gnome-screensaver > > will start a full-screen window and grab the keyboard and the pointer, > > that is to say, the user's session is locked. > > > > gnome-screensaver tells GDM that the user's session is locked. GDM will > > start initializing PAM and creates the unlock dialog if VT is > > enabled. > > > > 3. If the user moves the mouse or hit the keyboard > > > > 3a. If VT is enabled, gnome-screensaver will ask GDM to show the > > unlock > > dialog on another DISPLAY, and ask VT manager to switch to that DISPLAY. > > Then the user inputs the correct password, GDM tells gnome-screensaver to > > destroy the window and release the keyboard and the mouse. Do the VT > > switching > > to the user's DISPLAY. > > > > 3b. If VT is not enabled, gnome-screensaver will show the unlock > > dialog, interacting with GDM on PAM authentication. If the user input the > > correct password, gnome-screensaver will destroy the lock window and > > release the keyboard and the mouse. > > > > For 3a, since a new GDM session is created, and GDM has already supported > > the accessibility, we don't need more work to do. > > > > But for 3b, we need consider to support the accessibility for the > > unlock dialog. Here I CCed a11y list in order to hear their opinions. > > In both cases, GDM should launch the unlock GUI as the "gdm" user. > Since the gdm user has the Xauth key for the session, this should be > possible. Running as the "gdm" user is better from a TrustedPath > perspective. > > In the case of 3b, GDM will just launch the gdm-simple-greeter, and not > run a new gnome-session. Could we still run a gnome-session for the user 'gdm'? If the gdm's gnome-session is still running, things look simpler.
> If it is possible for GDM to run the login > panel, then this should be run to give access to the a11y features (note > that this may require that gnome-settings-daemon be run for the "gdm" > user). I'm not sure what should be done to make GDM GUI show on the same DISPLAY. Since gnome-screensaver has grabbed the keyboard and mouse, it should allows GDM GUI to grab them again. Also GDM GUI needs to cover the gnome-screensaver window. I do not know whether it is easy to implement something like this. Jeff > > If this is not possible, then perhaps a button needs to be added to the > GUI in this case to make it possible to pop-up a dialog to select what > a11y features should be turned on or off. > > It also may be acceptable to require VT to work for a11y features to be > available, and only to support a11y on displays that support VT. But > we need to discuss this. > > > Can I start a new at-spi-registryd for the unlock dialog? This daemon runs > > on a new DBUS session daemon listening on a new DBUS address. > > The unlock process and ATs will communicate with this session daemon, which > > will not affect the old daemon. > > If the lock screen dialog runs as the "gdm" user then a new > at-spi-registryd will need to be run as the "gdm" user for this to work. > > Brian _______________________________________________ gnome-accessibility-list mailing list gnome-accessibility-list@gnome.org http://mail.gnome.org/mailman/listinfo/gnome-accessibility-list
