The correct name should be XSECURELOCK_SAVER_STOP_ON_BLANK. We also
starts children when screensaver is on, but screen is not blanked, or
when screensaver is one and screen is blanked, but this option is not
enabled.

Useful for waking up the locker on system resume from suspend and
similar events not visible to X.

This enables children some time to initialize and prepare their
content. They are started before the main loop, we sleep
XSECURELOCK_SAVER_DELAY_MS, then map the windows. The saver window is
mapped first, then the background window and the obscurer window. This
order works fine for me and I don't get a black flash anymore, despite
the saver being written in Python.

On shutdown, the order is also a bit altered to reduce the flash due
to the obscurer window in white.

The multiplexer is left untouched as its parent window is not mapped.

Fix #94

Co-authored-by: Joshua Trees <me@jtrees.io>

* configurable background color with XSECURELOCK_BACKGROUND_COLOR

* Add docs regarding `XSECURELOCK_MULTIPLEX_BACKGROUND_COLOR`

Co-authored-by: Cullen Ross <cullenrss@gmail.com>

This also applies to `saver_mplayer`, hence the more generic name.

added annotation to where to find date format

Fixes #90.

That way, when a user ever sees it, they see the cause of the problem:

INCOMPATIBLE COMPOSITOR,
PLEASE FIX!

Should fix crash issues with nvidia driver.

Credit goes to tommie.

Also, provide a general variable
(XSECURELOCK_ALLOW_LOCKING_IF_INEFFECTIVE) to bypass these checks,
when wanting to develop XSecureLock itself on a Chromebook (Wayland!) for
example.

Works around issues in third-party authentication modules.

Fixes #39.

For now they're C99-only; possibly to be fixed later.

* Implement disco mode

* Add option to hide the password completely

* Update README.md

* Update README with new version of env variables (not yet implemented)

* Fix const-correctness

* Add XSECURELOCK_PASSWORD_PROMPT flag + 3 bonus prompts

* Remove XSECURELOCK_PASSWORD_PROMPT from readme

* Add "REMOVE IN v2" inside XSECURELOCK_PARANOID_PASSWORD setting name

* Revert accidental PARANOID_PASSWORD_MIN_CHANGE change

* Wrap _Static_assert in a macro

* Replace emoji escape codes with actual values

* Rename ShowFromArray function

* Use ++ as prefix operator

* Remove useless parentesis

* Move flag variables inside main

* Update README with samples for the different XSECURELOCK_PASSWORD_PROMPT values

Behaves somewhat better if the value is low; still could not get a zero value
to work, as X11 then still wakes up the screen on key-release events.

Note that after this change, SIGUSR1 is only sent if
XSECURELOCK_SAVER_RESET_ON_AUTH_CLOSE is enabled, and savers
should ideally handle it by soft-resetting the saver (implemented in
saver_xscreensaver only for now); not handling it will cause a hard-reset
of the saver by restarting it from scratch.

Fixes #75.

Make it run at 60fps by default now, no longer 112fps when dithering.

Internal reference: b/130370819.

Not doing so but running xsecurelock via shell expansion means that the shell
will keep holding on to the sleep lock FD, preventing suspend.

This signal is now sent from the main program to the saver to reset possible
idle timers in the savers, without intending to restart the saver.

This is part of the effort to make the auth child protocol more flexible and to
properly run auth on top of the saver as a window.

Example:

XSECURELOCK_KEY_XF86AudioPause_COMMAND='playerctl --all pause'

to control media players using https://github.com/acrisci/playerctl.

Fixes #37.

The old variable still works for compatibility if the new one isn't set.

Fixes #21.

It's then always shown on the screen with the mouse pointer.

Also added a macro SHOW_CURSOR_DURING_AUTH to actually show the pointer
- this is rather useless at the moment as auth helpers cannot receive
mouse events yet anyway. Still a nice proof of concept.

Add basic support for playing sounds during the auth flow.

Use XSECURELOCK_AUTH_SOUNDS=1 to turn them off. Requires a working X11
bell (usually provided on Linux by the pcspkr kernel module).

Also, always run the player with a playlist of 256 videos; this strikes a
balance between having too many pauses between videos while not eating
too much memory in the player.

Replaces pull request #56.

README said it was enabled, but it's disabled by default.

Mainly because some people found it annoying to include the seconds there, but there's no portable way to remove them.

Fixes #57.

Multiple screen lockers can interfere in various ways:

- First of all, log spam: only the first locker is usually able to lock at all. Any others will usually fail getting the required input grabs.

- Some lockers, e.g. light-locker, also have specific countermeasures against failing to lock and may interfere with xsecurelock. This has in the past caused issues such as having to unlock twice, having to unlock on a black screen because the graphics output broke, or losing all input focus after unlocking (yes, including alt-tab) and thus having a broken environment until clicking another window.

- Also, potential race conditions during startup of both at the same time might cause deadlocks (e.g. if one grabs mouse first and one grabs keyboard first, while retrying indefinitely).

- Even if they're not retrying indefinitely (xsecurelock isn't), this can slow down suspend to the point that systemd gives up and suspends before the screen is locked.

Should limit damage of the unmapping.

Also, optionally dump debug info about the first window unmapping which
helped (XSECURELOCK_DEBUG_WINDOW_INFO).

Also, moved the datetime buffer to a local variable given it isn't used
across functions, fixed formatting, and loaded the LC_TIME locale so we
can show local time formats.