Under i3 (not Xvfb), a managed tk.Tk() toplevel's geometry() request
was silently rewritten to the tiled pane size instead of the
requested WxH, so the content never actually overflowed and every
assertion built on "does this overflow" failed -- 11 tests across
test_fitcheck.py/test_scrollable.py. Fix: overrideredirect the
throwaway root, matching how every production lock window is already
built and for the identical reason (a WM must not be able to rewrite
geometry a fit/scroll check depends on).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018M5gKyYzxWG6QkCaj1wWfk
wait_for_turn only helps a weaker locker arriving after a stronger
one; it does nothing when the weaker one is already the incumbent.
On 2026-08-21 diet_guard (rank 100) held the grab for ~3 minutes
against a newly-arriving screen_locker (rank 200), which just
retried and logged instead of ever making progress.
Fix: when a grab is blocked by a holder that outranks-us-not, SIGTERM
it once. The holder's own signal handler already converts SIGTERM
into its normal close() teardown (VT restore, arbiter release,
app-specific on_close) -- this reuses that path rather than adding a
new one, and never signals upward (never disturbs an incumbent that
outranks us), so it cannot become a way to bypass a stronger lock.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018M5gKyYzxWG6QkCaj1wWfk
wait_for_turn/stronger_claims already fixed leetcode_guard's grab-race
with screen_locker; screen_locker and diet_guard never got the same
fix, so a stray re-arm race between them was still live (confirmed
2026-08-21: diet_guard held the global grab 07:04-09:07 while
screen_locker built a competing window and retried its own grab
forever instead of queueing).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018M5gKyYzxWG6QkCaj1wWfk
Phase 2 adds four exports (make_button, heading, row, WidgetGroup) plus a
wheel-scroll fix in ScrollableSurface. Minor, not patch: the surface grew.
Purely additive -- nothing was removed, so consumers still on the 0.4.1 pin
keep working unchanged.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U4Rj3s7K2qzrLNgJqqPhno
LockWindow.grab_input() only ever focuses the entry once, on first grab
acquisition (_notify_focus_ready is one-shot). A surface torn down and
rebuilt later -- a monitor going dark and recovering, which flaky DDC/CI
power control does routinely -- gets a brand new widget that nothing
ever focuses. The grab stays held, so no other window can take focus
either: the entry renders correctly but is permanently keyboard-dead
until the process restarts.
RecoveryLoop.tick() now re-runs the same focus_surface(preferred_focus_
index()) call whenever a tick's surface delta reports a newly created
output, mirroring what LockWindow does on first acquisition. Bundled the
loop's five collaborators into a RecoveryCollaborators dataclass rather
than growing its constructor past ruff's five-argument limit.
Diagnosed against a week of wake-alarm's real journal history: the
dismiss-code box rendered normally every alarm morning but accepted no
keystrokes, tracking exactly with HDMI-0's recorded dark/recover blips
near 07:00 and 07:55 each day.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NGAEbavLSCAotBqhVfFhPc
On 2026-08-03 the screen locker's lock screen scrolled to mid-content and
back with nobody touching the keyboard, on a 1366x768 panel. Measured under
Xvfb with the real app: one programmatic focus_set() produced three scrolls,
frac 0.000 -> 0.436 -> 0.145.
Two causes, both here:
* ScrollableSurface followed every <FocusIn>. The apps focus a widget on
every repaint (and gatelock re-asserts focus from its recovery tick), and
Tk delivers <FocusIn> to the focused widget's whole ancestor chain when the
toplevel takes X focus -- so each repaint aimed a scroll at containers
taller than the screen. Now a focus move scrolls only when it followed a
real keypress, or a click on the widget that took focus, and only for a
leaf. Tab onto a clipped field still reveals it; nothing else moves.
* finalize()'s reset-to-top cancelled the centring, because centring moved
the canvas item down and the region's top edge with it. The region is now
pinned to the viewport whenever the content fits, so the view cannot move
at all, the scrollbar is taken down, and centring survives the repaint.
Content that does not fit is a layout defect, not a mode to live in, so
finalize() reports it at warning and gatelock.measure_fit() lets each app
gate on it before shipping (scripts/verify_screen_fits.py in all four).
Also: LockConfig's type/space scales now compact below 768px (_density),
which is where a screen has no room to be at design-system size and no
scrollbar to make up for it. 768 and up is verified to fit at full size, so
it is never compacted.
Tests: _scrollable had none; the regression is now stated as code
(programmatic focus must not move yview; Tab must). 323 pass, coverage
95.38% -> 99.44%.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BsXnTHyuuCUZsqetTaajcF
gatelock v0.3.0. Every change here works around a Tk *default*, not an
application mistake -- which is why they belong in the shared backend rather
than being fixed four times.
On a lock surface these are not accessibility niceties. The lockers hold a
global input grab with VT switching disabled, so a control the keyboard cannot
reach, or a button clipped off the bottom of the screen, is a bricked machine.
LockConfig gains a type scale, a spacing scale and a focus-ring token:
- font() applies Tk's sign convention. Tk encodes the unit in the SIGN of the
font size -- positive is points, negative is pixels -- so passing the
design system's px values straight through rendered every string ~30%
oversized (measured: body at 16pt has a 26px linespace where 16px gives 20).
That alone pushed diet_guard's meal gate to 866px of content inside a 739px
pane on a 1366x768 screen.
- focus_kwargs() sets highlightcolor, the *focused* ring. Tk's default is a 1px
BLACK ring, invisible against the palette's #211D1B background. Note
highlightbackground is the UNfocused ring: setting only that one inverts the
affordance, which is what diet_guard was doing.
_keyboard.py collects three Tk defaults that each make a form unusable:
- tk.Text traps Tab (inserts a literal tab and refocuses itself) and no-ops
Shift-Tab; the only exits are the undocumented Ctrl+Tab / Ctrl+Shift+Tab.
- tk.Button binds <space> on X11 but never <Return>, so the key a user reaches
for to submit does nothing.
- Escape needs binding at the toplevel to work wherever focus happens to sit.
_scrollable.py adds ScrollableSurface, a viewport that content can actually be
reached in:
- A place()-centred frame takes its *requested* size and is clipped
SYMMETRICALLY, so overflow removes the heading and the submit button at the
same time, with no scrollbar and no hint anything is missing.
- A bare tk.Canvas has no class key bindings, so ::tk::FocusOK rejects it as a
focus stop and the only way to scroll is dragging the thumb with a pointer.
- Canvas clipping does not unmap children, so scrolled-out fields stay in the
tab ring while Tk never scrolls to follow focus -- Tab lands on fields the
user can neither see nor reveal.
- A Canvas holds content in a canvas *item*, so it never propagates the
content's requested size; a toplevel told to size itself has nothing to grow
to. _request_content_size() fixes that, clamped to the display.
center_when_fits keeps short screens looking exactly as they did, so the
viewport can replace a centred frame without a visual change.
A scrollable dialog Toplevel is deliberately NOT the mechanism: on an
override-redirect lock surface a second toplevel steals the Tk grab, which the
recovery tick then kills -- the 2026-07-26 failure where a frozen sport
selector logged a walk as table tennis.
unified-design-system gains the two rule families this implements (pointer-free
operability, 1366x768 usable / 1024x600 graceful), a focus-ring token, and the
px/pt sign convention written down so it cannot recur.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Releases the two fixes from the previous commit so the four consumers
(screen-locker, diet-guard, wake-alarm, testsAndMisc) can pin them: holds_grab
no longer steals the grab back off our own posted menus, and a raising tick
no longer permanently stops the recovery loop.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
On 2026-07-25 the PC appeared frozen and needed an SSH rescue. Three defects
stacked:
1. DP-0 came up `connected` with a valid EDID and no mode/CRTC -- physically
dark, while X still reserved its 3840px slice of the root window.
2. diet-guard-gate and workout-locker each mapped an override-redirect window
spanning the WHOLE root (6400x1440+0+0), centring their controls on the
primary output -- the dark one. The escape UI was invisible.
3. They deadlocked on the X grab, and the loser logged "another app -- e.g. a
fullscreen game -- holds it". No game was running; the holder was the other
locker. That guess sent the diagnosis the wrong way for the whole outage.
The library had no concept of an individual output: setup() sized the window
from winfo_screenwidth(), the union bounding box of every output.
What changes:
* _outputs.py An output is LIVE only if connected AND has a mode/CRTC.
RandR (crtc==0 or mode==0) and an xrandr --query parser derive
that predicate independently; verified to agree exactly on the
real DP-0/HDMI-0 layout. Fails closed three distinct ways.
* _surfaces.py One window per live output at its own geometry, and the only
module allowed to create/move/destroy windows. Explicit
geometry replaces attributes(fullscreen=True), which an
override-redirect window is invisible to anyway.
* _detect.py RandR events + Tk <Configure> + xrandr polling, coalesced. The
RandR thread runs on a private X connection and may only call
queue.put -- Tk is not thread-safe.
* _recovery.py Re-asserts coverage, placement, grab and VT on a timer. Proven
monotonic: it may only ADD coverage or RE-ACQUIRE the grab. An
ast test asserts the file contains none of grab_release /
restore_vt_switching / close / destroy / quit / withdraw, while
disable_vt_switching and grab_set_global ARE present. Yanking
every cable therefore does not unlock anything.
* _arbiter.py N-app priority: wake_alarm > screen_locker > diet_guard.
Liveness is proved by flock-on-death -- no heartbeat, no PID
scan, no clock. A two-axis strength check stops rank ever
weakening the lock: an app stands down only for an incumbent
at least as strong on BOTH grab kind and VT disabling.
* _guards.py wait_for_x_server replaces wait_for_display and gates ONLY on
an X server existing. Output count must never gate arming:
zero live outputs means lock without showing, not decline to
lock. That inversion is what left the machine unlocked.
* _window.py Arms first, renders second. Names the real grab holder instead
of blaming a fullscreen game. Releases the arbiter on close so
the alarm -> workout handoff cannot strand the next app.
Two bugs found by running it, not reading it:
* acquire_holder() opened the holder file "w", which truncates at open() --
before the lock attempt. A losing contender erased the incumbent's claim, so
the app that most needed to know who held the screen found an empty file.
* tk.Toplevel over a MagicMock sends real tkinter into infinite mock recursion;
the suite hung instead of failing, and an unpatched setup() would have run
setxkbmap against the developer's own machine. conftest now has an autouse
hermetic fixture; the suite went from >120s to 0.7s.
235 tests, 100% branch coverage, ruff (select=ALL) and mypy --strict clean.
No suppressions added: Protocols replace Any for python-xlib, public attribute
access replaces ._data, and type-only Protocols live under TYPE_CHECKING.
Consumers still pin gatelock-v0.1.1 and are unmigrated; nothing ships until a
tag and a reinstall into system python.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Mirrors the palette rework already applied to diet-guard/dufs-cloud/
screen-locker. Adds `on_fill` (dark) for text drawn on a filled accent/
success/warning/danger surface -- near-white text under-contrasts on all
four (measured 2.2-3.6:1, below the 4.5:1 floor); dark text passes 5.8-9.7:1
on every one of them.
Bumps to 0.1.1 since this is a real release: the 3 consumer repos pin
gatelock to a git tag, not editable.
Extracted from wake_alarm, screen-locker, and diet_guard, which each
independently implemented fullscreen-lock, input-grab, VT-disable, and
HMAC-signed-state mechanics at different levels of maturity (the HMAC
module was already a hand-copied duplicate between two of them).
LockConfig exposes overrideredirect/grab/disable_vt as independent
axes so one LockWindow can reproduce all three projects' exact prior
behavior, plus screen-locker's confirmed upgrade to retry-forever grab.
