Olpc-utils
olpc-utils localization and configuration subsystem
The current configuration scheme is implemented in olpc-utils (before, it was scattered through initscripts, sugar and pilgrim).
We strive to minimize the number of system files we write to, and keep our deviations from Linux as backwards compatible as possible. User controlled files are kept in /home/olpc, so they get automatically preserved on updates.
/etc/init.d/olpc-configure
Runs early at system boot to do some OLPC-specific initializations and the first-boot configuration.
The first-boot configuration is conditionalized on the /home/olpc/.olpc-configured flag.
olpc-configure writes language and keyboard settings to /home/olpc/.i18n, overridable by users.
/etc/sysconfig/i18n is only used by initscripts, and should contain LANG=C for improved performance (cuts 5-6 seconds from the boot).
We preferably specify XKB keyboards with the layout(variant) syntax because it's more intuitive when you have two or multiple layouts. The separate layout and variant syntax is still supported.
For MP machines, we set the keyboard directly from mfg data, without a hardcoded table to map mfg tags to XKB layout names. TODO
The Linux console keyboard is still not being set accordingly. Not sure if we really want to do it. Power users can run loadkeys themselves if they really want to.
/etc/X11/xorg.conf
xorg.conf is now a symlink created by olpc-configure, pointing to one of two possible fixed configuration files, that don't need exceptional handling for the update process.
We still handle some differences between Geode+DCON and emulators. I'd like to get X to autodetect these things better so we could kill off the configuration files altogether.
We're currently missing a way to allow user customizations in xorg.conf. In the future, we could make olpc-dm check for /home/olpc/.xorg.conf and use it if present. On the other hand, customizing xorg.conf is for power users who may also want to customize other /etc entries. So if we really want to support these use cases, we'd be better off finding a generic way to preserve user customizations.
/usr/bin/olpc-dm
This is our display manager, a streamlined equivalent of GDM or KDM. So streamlined that it doesn't even have a UI. It could be extented to support multiple users, XDMCP and other fancy things.
olpc-dm currently spawns the X server and the session through startx and xinit, but there are plans to make it do it directly. This will also allow us to do something smarter than SysVinit's once/respawn modes for restarting X.
BUG: olpc-dm still hogs the console and dies when you hit ^C. The fix is not a one-liner, and it's not a critical bug, but we're planning to fix it some day.
/usr/bin/olpc-session
This script replaces /home/olpc/.xinitrc. It sources /home/olpc/.i18n for $LANG, $XKB_LAYOUT and, optionally, $XKB_VARIANT.
The last action olpc-session does is spawning the Sugar shell.
/home/olpc/.xsession
This is an "extensibility hook" for customizing your session. It gets sourced near the end of /usr/bin/olpc-session. A default is provided as .xsession-example, with some tips you may want to review.
This file also replaces the old /home/olpc/.sugar.debug