Meson Buildsystem recipe collection that handles Kconfig and .config files.

This meson project can be used as a sub-project for every meson based project which uses Kconfig as configuration system. The top level Kconfig is parsed at configure time (i.e. during meson setup), the config file is checked and a build specific .config file is generated using oldconfig policy for missing Kconfig entry. During project configuration, two dependencies file are generated, one which listed all Kconfig files that are parsed, and the .config itself. Thus, if any of those file change (Kconfig new options and/or a manually run menuconfig), the project is automatically reconfigure by Meson. This project provides a meson configuration_data object containing all .config entries (field to y are converted to 1/0 boolean) and a config.h is generated using meson configure_file feature.

The provided configuration_data can be reused for Meson source_setconfiguration.

• kconfig: Top level Kconfig file.
• config: input config file.

NOTE: This is up to the user to provide the input config file (e.g. from a defconfig, and/or after config fragment merge operation). This can be done w/ scripts/kconfig.py but this is out of scope of the meson configuration step.

Options got yield attribute and thus can be defined at top-level project and forwarded to sub projects seamlessly

Kconfig can use environment variables substitution in kconfig file and/or dotconfig. This recipe export a meson variable named kconfig_env to be used as env keyword argument value for meson function (see: https://mesonbuild.com/Reference-manual_returned_env.html).

• srctree: standard kconfig variable for top level source directory (a.k.a. meson global source tree).
• subprojects: helper to path to top level subprojects directory. This ease subprojects Kconfig files source from top level `Kconfig`` file.
• KCONFIG_CONFIG: Outputted dotconfig file path.

kconfig_env is also added to the meson devenv. Meson devenv is a python-virtual-env-like feature that allowed developers to enable the required variables for the project. Using this, one can activate the project devenv and directly use menuconfig from kconfiglib w/o the need of any helper or custom command.

e.g.

meson devenv -C builddir
menuconfig

There is a helper target called menuconfig for users who wants to edit the configuration during development. This target handles the path of top-level Kconfig and output .config.

• menuconfig: runs menuconfig inside the given builddir

TODO: Add oldconfig, savedefconfig targets

The following variables can be use by top level project to use Kconfig features. (see: https://mesonbuild.com/Reference-manual_returned_subproject.html)

• kconfig_env: environment variables set
• kconfig_data: kconfig meson configure_data w/ entry set to y converted as 1/0 boolean
• kconfig_h: C header generated at configure time by meson from processed kconfig_data
• kconfig_rustargs: Rust flags generated at configure time by meson from processed kconfig_data

This project uses kconfiglib python package as Kconfig frontend. One could install it with the following:

pip3 install --user kconfiglib

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

NOTE: This project bundles a modified version kconfig.py from Zephyr project, licensed under ISC.