WIP scripts for Apple II demo loop on Raspberry Pi

linapple-loop

#!/usr/bin/env bash

# Script for running the LinApple emulator fullscreen and with autoboot.
# The intention is to keep it running unattended.

# System is set to autologin as a particular user without requiring password.
# This script can be run from a .desktop file in .config/autostart so that it
# runs on system boot.

# The demo loop I want to run seems to freeze sometimes. So, every 5 minutes
# we'll take a screenshot, alternating between "shot1.png" and "shot2.png".
# If the two shots are the same, tell LinApple to do an emulated system reboot.
# Also since LinApple isn't meant to be an always-running application -- who
# knows if there are issues lurking there -- I'll just completely restart the
# LinApple process between 3:00 and 3:05 AM.

# Screenshot courtesy of fbgrab from https://github.com/GunnarMonell/fbgrab


# Conservatively, sleep first to let the booted system get its footing a bit.
sleep 3

# Define the periodic check, and start it going in the background.
bindir=/home/demouser/bin
shotdir=/home/demouser
nextshot=shot1.png
function checkloop {
  while true
  do
    # Sleep for 5 minutes.
    sleep 300
    # If in [3:00, 3:05) interval do a shutdown (process will restart), else
    # do the screenshot check. I'm aware there are at least two ways this code
    # could miss that window, but it's good enough... the daily shutdown doesn't
    # need to be absolutely 100% bulletproof. If that turns out to be an issue
    # then I'll do this differently.
    hour=$(date +%H)
    minute=$(date +%M)
    if [[ $hour == 03 && $minute =~ 0[0-4] ]]
    then
      # Shutdown time!
      # Arguably we should check to see if this graceful shutdown works, and if
      # not then do a process kill. But, meh.
      $bindir/linapple-quit
    else
      # OK let's take a screenshoot...
      $bindir/fbgrab $shotdir/$nextshot > /dev/null 2>&1
      # Toggle the name for the next one.
      if [[ $nextshot == shot1.png ]]
      then
        nextshot=shot2.png
      else
        nextshot=shot1.png
      fi
      if cmp $shotdir/shot1.png $shotdir/shot2.png > /dev/null
      then
        # Screen is frozen, let's ask for a reset.
        $bindir/linapple-reset
      fi
    fi
  done
}
checkloop &

# Now run the emulator, restarting if it exits.
while true
do
  /path/to/LinApple/build/bin/linapple -f --autoboot
  sleep 1
done

linapple-loop.desktop

[Desktop Entry]
Name=LinApple Loop
Exec=/home/demouser/bin/linapple-loop
Type=Application
Encoding=UTF-8
Categories=Other;
Terminal=true

linapple-quit

#!/usr/bin/env bash

# Ask LinApple to shut down. Used by linapple-loop; also can be handy for
# manual use (sets DISPLAY so it doesn't need to be invoked from the desktop
# session... e.g. can be used while ssh'ing in).

DISPLAY=:0.0 xdotool search --class linapple windowactivate --sync %1 key F12

linapple-reset

#!/usr/bin/env bash

# Ask LinApple to do an emulated reboot. Used by linapple-loop; also can
# be handy for manual use (sets DISPLAY so it doesn't need to be invoked
# from the desktop session... e.g. can be used while ssh'ing in).

# Normally LinApple uses Ctrl+F2 for an emulated reboot, but for whatever
# reason I can't seem to send that key combo to it in this way. Instead I
# modified LinApple to accept plain F2 for reboot.

DISPLAY=:0.0 xdotool search --class linapple windowactivate --sync %1 key F2 windowactivate $(DISPLAY=:0.0 xdotool getactivewindow)