xrdb hintstyle is not correctly updated

[Chris Cheney]

Binary package hint: gnome-settings-daemon

There appears to be a threading issue in gnome-settings-daemon when calling xrdb in xft_settings_set_xresources(). I added debugging to xft_settings_set_xresources() and noticed it was being called properly but the Xft.hintstyle wasn't being updated when changed in System->Preferences->Appearace->Fonts->Details. I tried stracing g-s-d to see if xrdb actually was being called and then it started working 100% properly every time, hence I am pretty sure this is a threading issue of some sort. As soon as I killed strace the problems started up again.

To reproduce this bug do the following:

Have a gnome-terminal window open and run this after changing settings:
xrdb -query

Go to System->Preferences->Appearance->Fonts->Details and change the font hinting to various modes, after each change run the xrdb -query above and notice that often it does not actually update the setting in xrdb. Then run strace on g-s-d and notice it works every time.

Seen on: Core 2 Duo - Ubuntu Jaunty amd64

Chris

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
Package: gnome-settings-daemon 2.26.0-0ubuntu3
ProcEnviron:
 SHELL=/bin/bash
 LANG=en_US.UTF-8
SourcePackage: gnome-settings-daemon
Uname: Linux 2.6.28-11-generic x86_64

[Chris Cheney (ccheney)]

I forgot to mention that the program is being called via spawn_with_input() which does threading and a bug in that function is probably the culprit.

[Chris Cheney (ccheney)]

Also I forgot to mention that the reason I am noticing this bug is due to the fact that OpenOffice.org uses the xrdb information and when it isn't correct it causes OOo to look wrong versus other Gnome desktop apps.

[Sebastien Bacher (seb128)]

the command is called using a classic g_spawn_async call there is no threading used there, that requires to do some extra debugging

[Alexander Sack (asac)]

i always thought it just spawns a process. For me xrdb was kind of a legacy thing and never expected it to update everywhere instantaneously. If thats supposed to be instantanous its a bug I also saw I think.

Chris, if you change your setting and re-log in, is the xrdb -query output correct?

[Alexander Sack (asac)]

can you please add g_warning output at the beginning of spawn_with_input and child_watch_cb so we get an idea if we see some kind of race there.

[Alexander Sack (asac)]

... moved discussion to upstream bug.

[Rick Spencer (rick-rickspencer3)]

Alexander - this is currently set to release critical, so should be assigned. Please re-assign if appropriate. Also, is this really a release blocker? Is Importance really High?

[Chris Cheney (ccheney)]

I think this isn't really a release blocker unless the repercussions of what is happening here is more serious than I realize. There is apparently a race condition caused by async executing xrdb, setting the old values when attempting to set new values, and doing so multiple times. This appears to end up causing xrdb to set the old values instead of the new values the user just selected in the gui. This ends up causing anything that uses xrdb, such as OOo, to look wrong when compared to Gnome. Restarting their session after each time they change the value should resolve this issue as far as I know, but users don't know to do this since the change in Gnome takes effect immediately.

Chris

[Martin Pitt (pitti)]

not a jaunty blocker

[Sebastien Bacher (seb128)]

the issue is only when changing the settings in the capplet not at every login, doesn't seem a high priority or importance bug