libratbag provides ratbagd, a DBus daemon to configure input devices, mainly gaming mice. The daemon provides a generic way to access the various features exposed by these mice and abstracts away hardware-specific and kernel-specific quirks.
libratbag currently supports devices from Logitech, Etekcity, GSkill, Roccat, Steelseries. See the device files for a complete list of supported devices.
Users interact through a GUI like
Piper. For developers, the
ratbagctl tool is the prime tool for debugging.
Installing libratbag from system packages
libratbag is packaged for some distributions, you can use your system's package manager to install it. See the wiki for details.
libratbag uses the meson build system which in turn uses ninja to invoke the compiler. Run the following commands to clone libratbag and initialize the build:
git clone https://github.com/libratbag/libratbag.git cd libratbag meson builddir ninja -C builddir sudo ninja -C builddir install
The default prefix is
/usr/local, i.e. it will not overwrite the system
installation. For more information, see the
And to build or re-build after code-changes, run:
ninja -C builddir sudo ninja -C builddir install
builddir is the build output directory and can be changed to any
other directory name. To set configure-time options, use e.g.
meson configure builddir -Ddocumentation=false
meson configure builddir to list the options.
Running ratbagd as DBus-activated systemd service
To run ratbagd, simply run it as root
sudo ratbagd. However,
ratbagd is intended to run as dbus-activated systemd service and installs
the following files:
/usr/share/dbus-1/system.d/org.freedesktop.ratbag1.conf /usr/share/dbus-1/system-services/org.freedesktop.ratbag1.conf /usr/share/systemd/system/ratbagd.service
These files are installed into the prefix by
ninja install, see also the
Developers are encouraged to simply symlink to the files in the git
For the files to take effect, you should run
sudo systemctl daemon-reload sudo systemctl reload dbus.service
And finally, to enable the service:
sudo systemctl enable ratbagd.service
This places the required symlink into the systemd directory so that dbus activation is possible.
The DBus Interface
Full documentation of the DBus interface to interact with devices is available here: ratbagd DBus Interface description.
libratbag Internal Architecture
libratbag has two main components, libratbag and ratbagd. Applications like Piper talk over DBus to ratbagd. ratbagd uses libratbag to access the actual devices.
+-------+ +------+ +---------+ +-----------+ | Piper | -> | DBus | -> | ratbagd | -> | libratbag | -> device +-------+ +------+ +---------+ +-----------+
Inside libratbag, we have the general frontend and API. Each device is handled by a HW-specific backend. That HW backend is responsible for the device-specific communication (usually some vendor-specific HID protocol).
+---------+ +-----+ +------------+ +----------+ | ratbagd | -> | API | -> | hw backend | -> | protocol | -> device +---------+ +-----+ +------------+ +----------+
The API layer is HW agnostic. Depend on the HW, the protocol may be part of the driver implementation (e.g. etekcity) or a separate set of files (HID++). Where the protocol is separate, the whole known protocol should be implemented. The HW driver then only accesses the bits required for libratbag. This allows us to optionally export the protocol as separate library in the future, if other projects require it.
Adding Devices to libratbag
libratbag relies on a device database to match a device with the drivers.
See the data/devices/
directory for the set of known devices. These files
are usually installed into
Adding a new device can be as simple as adding a new
.device file. This is
the case for many devices with a shared protocol (e.g. Logitech's HID++).
file for guidance on what information must be set. Look for existing devices
from the same vendor as guidance too.
If the device has a different protocol and doesn't work after adding the device file, you'll have to start reverse-engineering the device-specific protocol. Good luck :)
git clone https://github.com/libratbag/libratbag.git
Bugs can be reported in our issue tracker
libratbag discussions happen on the input-tools mailing list hosted on freedesktop.org
A number of device-specific notes and observations can be found in our wiki: https://github.com/libratbag/libratbag/wiki/Devices
libratbag is licensed under the MIT license.
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: [...]
See the COPYING file for the full license information.