Session management

Abilities

• Offer to log out from the existing session
• Launch a D-Bus session bus?
• Detect the Qt platform (eglfs, etc)
  • Detect hardware-specific platform options
  • Detect libinput
• Listen for SIGINT/SIGTERM and log out of the session
• Set up the process environment
• Launch and manage applications
• Provide the freedesktop screensaver interface
• Manage the lock screen state
  • Lock screen authentication?
• Manage virtual terminals
• Power management
• Log out functionality

Architecture

• Shell
  • Separate QML UI instance for each screen
  • Listen to the session to:
    • Unlock/lock the screen
    • Black out the screen before sleeping
    • Display a wave animation and spinner when shutting down
  • Register to the power buttons and display the power dialog as appropriate
  • Check and display inhibitors before shutting down/logging out/etc
  • Pass idle status to the session
• Session
  • Send power actions to logind
  • Register for local control of the hardware power keys
  • Pass idle status to the session
  • Register a session instance
    • Listen for lock/unlock signals and pass it to the shell
  • Provide the freedesktop screensaver interface
  • Provide a session manager interface
    • Manage inhibit locks from applications
      • Manage login-related inhibitor locks locally
      • Pass system-related locks on to logind
    • Listen for logout/power-related actions from the shell
      • Do any local work and then call logind as necessary
  • Autostart applications when the shell starts
  • Handle launching applications and stopping them on logout/poweroff