UPower

Requirements:

  glib-2.0             >= 2.66.0
  gio-2.0              >= 2.16.1
  gudev-1.0            >= 235    (Linux)
  libimobiledevice-1.0 >= 0.9.7  (optional)
  polkit-gobject-1     >= 124

UPower is an abstraction for enumerating power devices, listening to device events and querying history and statistics. Any application or service on the system can access the org.freedesktop.UPower service via the system message bus.

Debugging

When doing bug reports, the following information can be useful:

• grep . /sys/class/power_supply/*/*
  This includes the current kernel view of all power supplies in the system. It is always a good idea to include this information.
• udevadm info -e
  This shows the hardware configuration and is relevant when e.g. the type of an external device is misdetected.
• upower -d
  Shows upower's view of the state
• upower --monitor-detail
  Dumps device information every time that a change happens. This helps with debugging dynamic issues.
• udevadm monitor
  Dumps the udev/kernel reported hardware changes (and addition/removal). This is helpful when debugging dynamic issues, in particular if it is not clear whether the issue is coming from the kernel or upower.

In addition, it can also be useful to run upower in debug mode and post the logs. There are two ways of doing so:

• Run upower daemon manually, you can do so using: sudo /usr/libexec/upowerd -rd
• Modify the systemd service and restart. This is best done by:

  1. sudo systemctl edit upower.service

  2. Adding the two lines:

     [Service]
     Environment=G_MESSAGES_DEBUG=all
     

  3. sudo systemctl restart upower.service

  4. Grab logs using journalctl -u upower.service or similar

Using tartan

Tartan is a LLVM static analysis plugin built to analyze GLib code. It can be installed and then run using:

mkdir build
cd build
meson setup ..
SCANBUILD=../contrib/tartan.sh ninja scan-build