30d2d992303433049b770516089995210d2da355
5
Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
 ekklesiaandClaude Opus 5
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27cd64a668 |
fix: the room asks for its output again, not only once at boot
River Kids came up silent on stable 0.2.2. The decision this policy makes
was right and was never asked for.
classroom-audio applied its policy once at startup and then only when a
PipeWire event arrived. pactl talks to PipeWire's PulseAudio server, and
the unit was ordered after pipewire and wireplumber but not after that.
At boot it therefore raced the server and lost: the single startup apply
failed with "Connection refused", the subscription attached cleanly a few
seconds later, and from that moment the daemon waited for an event that
had already happened. systemd said active, the subscription was live, and
the policy had never run at all.
That is why the card was found on output:analog-stereo+input:analog-stereo
with its HDMI port available. That profile is WirePlumber's own pick, not
one this policy would ever produce, which is the evidence it never ran.
Reproduced in the lab against real PipeWire 1.4.2 and WirePlumber 0.5.8 by
starting the daemon with pipewire-pulse stopped and then starting it: the
old daemon sits idle forever, the new one converges.
The shape is now: wait for the server, apply, subscribe, apply again the
moment the subscription attaches, and coalesce each burst of events into
one decision. Applying on attach is the fix for the race. While the room
has not got the output it would prefer it also looks again on a backing
off timer capped at a minute, so a television switched on hours later is
picked up whether or not ALSA's jack change ever reaches us as an event.
Once the room has what it wants it stops looking entirely, and a machine
with no digital output never looks at all.
Also here, all of it found by measuring the real server rather than
reading the code:
* sink lookup matched on fields a sink does not have. Two of its three
conditions could never be true; the one that worked returned whichever
sink of the card came first rather than the one for the chosen port.
* volume and mute are no longer touched. The old code unmuted and forced
70% on every output change, so every television power cycle reset a
volume the teacher had set and could unmute an output muted on
purpose. WirePlumber already remembers volume per device. A machine
this policy has never configured still gets 70% once.
* the profile chosen keeps the card's input, which is the difference
between output:hdmi-stereo and the output:hdmi-stereo+input:analog-stereo
an administrator reaches for by hand.
* a card profile is only set when it is not already in place, and only
so many times, so a sink that never appears cannot become a switching
loop.
* a machine with no sound server at all says so once and backs off,
rather than filling the journal. pactl subscribe's own stderr is
dropped because saying it is this daemon's job, and a subscription is
only treated as healthy once it has lasted, since pactl starts
successfully and then fails to connect.
* the fixtures described a machine nobody has. Real pactl puts no
"direction" on a port at all and says "availability unknown" rather
than nothing, so a test could not have caught this.
Existing streams are moved explicitly. Measured both ways on the real
stack: changing the default sink does move a stream that never asked for
a particular sink, but a stream pinned to a device stays where it is with
no policy running, and this moves it back without the application being
restarted.
tests/test-classroom-audio-daemon.sh drives the real daemon through the
boot race, a television switched on with and without an event announcing
it, a power cycle, a set that never comes on, and a room already correct.
It uses a pactl mock because no loopback or dummy sound driver has an HDMI
port, so the one thing a lab cannot prove is that the real jack change
arrives; docs/testing.md carries the physical procedure for that and says
not to take a passing build as evidence of it.
Co-Authored-By: Claude Opus 5 <[email protected]>
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ekklesiaandClaude Opus 5
|
23dff0b7b4 |
feat: close the chord that let a teacher hibernate the room
Ctrl+Alt+Delete opened Plasma's session screen and a teacher hibernated a classroom computer from it. A hibernated room cannot be recovered by anybody standing in front of it, which on a Sunday morning is everybody. logout=false was already set and did not stop it. That restriction governs Plasma's own actions — what plasmashell draws in a menu or an applet. The chord is a KGlobalAccel shortcut registered by ksmserver and it asks D-Bus for the greeter without consulting a Plasma action at all. A restriction on a menu cannot see a key. Three layers, because each one alone has a way past it. The key. kglobalshortcutsrc unbinds every ksmserver session action and PowerDevil's Sleep, Hibernate, PowerDown and PowerOff, each entry marked immutable. It is deliberately not in the xdg directory with the other settings: kglobalacceld opens that file as a SimpleConfig, so it reads one file in the teacher's home and no system directory at all. Measured — with it in the cascade, kreadconfig6 reported the chord unbound while the shortcut server went on answering Ctrl+Alt+Del. classroom-desktop-reset copies the package's copy into place before the shortcut server starts, the same way the panel is copied out of the package at every login. The policy. A polkit rule refuses login1.suspend* and .hibernate* for the classroom user and for nobody else. This is the layer that matters: a key can be unbound and anything reaching logind can still ask. Refusing here rather than masking sleep.target keeps a technician's own account working, and is also what tells Plasma to stop drawing the button — CanSuspend and CanHibernate come back no. Hybrid sleep and suspend-then-hibernate have no action of their own in systemd 257; both are authorised through hibernate, so denying it denies all three. The greeter. Its D-Bus activation is shadowed with /bin/false, the same mechanism already used for the old notification daemon. Layer one removes the caller, this removes the callee. Measured in the lab, from the package, after a reboot: the escape reproduced first with the shadow removed — the greeter really does start — and then refused, exited 1, with it back. The chord reports nothing bound. systemctl suspend as the classroom user is denied. The maintenance chord and the display chord both still answer, by key code, after the shortcut file is replaced wholesale. A root process may still suspend, hibernate, reboot and power off. 182 checks pass across a logout and back. Screen locking stays disabled, the power button still does nothing, and reboot and shut down are not newly denied to anybody. Co-Authored-By: Claude Opus 5 <[email protected]> |
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ekklesiaandClaude Opus 5
|
d2d30d6b0c |
feat: take the last of sway out of the classroom
The DVD player was the only thing still speaking a compositor the room no longer runs. It asked sway's tree whether VLC's window had really gone fullscreen, because VLC reports playing while its window is still the black startup one the loading cover exists to hide. VLC's own status was measured as a replacement and is not one: it reports fullscreen true in the same 250ms poll as playing, because the flag is the option it was started with and not a report about its window. So the cover is held for a floor and capped by the deadline that was already there, and the compositor is not asked anything. Focus-or-launch went the same way. The session already takes an exclusive lock, so a second one cannot start, and bringing an existing one to the front is the panel's job. classroom-window, classroom_sway and classroom_chrome are gone with it — the last of them was reachable from nothing at all. DVD also moves out of the status row, where it sat beside the clock as though a disc were a machine reading. It is an application: it is in the row with Wonder Ink and the browser, and classroom-provision removes it from the layout on a machine with no optical drive, which retires DVD_ENABLED. A computer that moves between rooms takes its drive with it; nobody remembers to edit a file when it does. The panel is rebuilt from the package at every login now. Plasma keeps whatever panel it first built, so an update could change the bar in the package and never change it in a room — measured, with an icon that outlived the file it came from. Editing the live panel configuration was tried instead and destroyed the panel, because the shell owns that file. Removing it before the shell starts is safe and makes the desktop stateless. Co-Authored-By: Claude Opus 5 <[email protected]> |
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ekklesiaandClaude Opus 5
|
2ff9d47be9 |
feat: decide the classroom's audio output from what is plugged in
The room that prompted this had a television on HDMI with working PCM audio and nothing in the analog jack, and WirePlumber chose analog. A teacher who corrected it by hand then had to restart the browser before any sound came out. The policy is a pure function so it can be tested against that room rather than against a machine: an unavailable port is not a candidate, an analog port merely existing is not evidence of a cable, and an explicit AUDIO_OUTPUT overrides the lot. Twelve cases, the real room among them. The daemon follows PipeWire's own event stream rather than polling, and moves streams that are already playing, which is the part that stops a teacher having to close and reopen the browser. Co-Authored-By: Claude Opus 5 <[email protected]> |
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ekklesiaandClaude Opus 5
|
87b55761c6 |
feat: give the classroom a desktop instead of a shell
The whole appliance UI is now configuration for a desktop Debian already ships: a Plasma 6.3 session with a colour scheme, a look and feel package that builds the bar, window rules, and KDE's own Kiosk restrictions. Two things were measured rather than assumed, and both changed a decision. Plasma restarts a crashed panel three times a minute and then gives up, which is the failure a classroom has already had. Four lines of systemd drop-in make it unconditional; the panel then survived eight SIGKILLs a second apart, back each time in 2.4s. Plasma draws a minimised task and a background task identically, so the five states the room needs cannot all be shown. Rather than write a task manager, the classroom removes minimise: clicking a launcher always means show me this. Co-Authored-By: Claude Opus 5 <[email protected]> |