Bug#1030000: fontconfig: after upgrade from 2.13.1-4.5 to 2.14.1-3 subpixel is enabled

[Thorsten Glaser]

Hi Andreas,

a bit out of order, but easier to respond (I’m a bit under the
weather so excuse any issues ahead of time):

>By 'disabled' I assume you mean 'Never', right?

Uhm, short walkthrough:

• Native
• Full
• Never
• Yes

>Did it also create 10-no-sub-pixel.conf ?

(sid-amd64)root at tglase:/etc # git status
On branch master
nothing to commit, working tree clean
(sid-amd64)root at tglase:/etc # ll fonts/conf.d/10*
lrwxrwxrwx 1 root root 53 Jan 31 21:25 fonts/conf.d/10-hinting-full.conf -> /usr/share/fontconfig/conf.avail/10-hinting-full.conf
lrwxrwxrwx 1 root root 53 Jan 31 21:25 fonts/conf.d/10-no-sub-pixel.conf -> /usr/share/fontconfig/conf.avail/10-no-sub-pixel.conf
lrwxrwxrwx 1 root root 54 Jan 13 21:30 fonts/conf.d/10-yes-antialias.conf -> /usr/share/fontconfig/conf.avail/10-yes-antialias.conf

>Have you experienced this problem in previous upgrades?

Unsure. My main system runs bullseye now to avoid UsrMove,
and this is a sid/amd64 chroot. Maybe.

>Can you reproduce the problem at all?

Let’s see ☻

(sid-amd64)root at tglase:/etc # dpkg -i /var/cache/apt/archives/fontconfig-config_2.14.1-3_amd64.deb
(Reading database ... 330670 files and directories currently installed.)
Preparing to unpack .../fontconfig-config_2.14.1-3_amd64.deb ...
Unpacking fontconfig-config (2.14.1-3) over (2.14.1-3) ...
Setting up fontconfig-config (2.14.1-3) ...
Processing triggers for man-db (2.11.2-1) ...
(sid-amd64)root at tglase:/etc # git status
On branch master
Untracked files:
  (use "git add <file>..." to include in what will be committed)
        fonts/conf.d/10-sub-pixel-rgb.conf

nothing added to commit but untracked files present (use "git add" to track)


So, yes, I can easily reproduce it *and* I end up with *both*
10-no-sub-pixel.conf and 10-sub-pixel-rgb.conf symlinked (ouch).

Now here it comes:

(sid-amd64)root at tglase:/etc # rm fonts/conf.d/10-sub-pixel-rgb.conf
(sid-amd64)root at tglase:/etc # DPKG_MAINTSCRIPT_PACKAGE=fontconfig-config DPKG_MAINTSCRIPT_NAME=postinst sh /var/lib/dpkg/info/fontconfig-config.postinst configure 2.14.1-3
(sid-amd64)root at tglase:/etc # git status
On branch master
nothing to commit, working tree clean

It’s not the postinst alone…

(sid-amd64)root at tglase:/etc # DPKG_MAINTSCRIPT_PACKAGE=fontconfig-config DPKG_MAINTSCRIPT_NAME=prerm sh /var/lib/dpkg/info/fontconfig-config.prerm upgrade 2.14.1-3
(sid-amd64)root at tglase:/etc # DPKG_MAINTSCRIPT_PACKAGE=fontconfig-config DPKG_MAINTSCRIPT_NAME=preinst sh /var/lib/dpkg/info/fontconfig-config.preinst upgrade 2.14.1-3 2.14.1-3

It’s also not them, unless I’m calling them wrong?

I have another hunch:

/var/cache/apt/archives/fontconfig-config_2.14.1-3_amd64.deb/deb://CONTENTS/etc/fonts/conf.d/10-sub-pixel-rgb.conf exists.

And indeed, that’s it. While the symlink is shipped in /etc,
it is not listed in
/var/cache/apt/archives/fontconfig-config_2.14.1-3_amd64.deb/deb://DEBIAN/conffiles
and therefore not handled as conffile by dpkg but as regular
file that is always extracted when extracting the package,
overwriting what was there. (I’m not sure what Policy says to
conffile handling for symlinks; I vaguely recall that at some
point post etch or so, conffile handling was changed in Policy
to mandate inclusion of anything under /etc but I might mis‐
remember that.)

This will have to be today’s feedback from me, sorry.

Good luck,
//mirabilos
-- 
<igli> exceptions: a truly awful implementation of quite a nice idea.
<igli> just about the worst way you could do something like that, afaic.
<igli> it's like anti-design.  <mirabilos> that too… may I quote you on that?
<igli> sure, tho i doubt anyone will listen ;)