23 Creating a Custom Template Configuration Directory

If you are producing your own customized version of the build system for use by other users, you might want to provide a custom build configuration that includes all the necessary settings and layers (i.e. local.conf and bblayers.conf that are created in a new Build Directory) and a custom message that is shown when setting up the build. This can be done by creating one or more template configuration directories in your custom distribution layer.

This can be done by using bitbake-layers save-build-conf:

$ bitbake-layers save-build-conf ../../meta-alex/ test-1
NOTE: Starting bitbake server...
NOTE: Configuration template placed into /srv/work/alex/meta-alex/conf/templates/test-1
Please review the files in there, and particularly provide a configuration description in /srv/work/alex/meta-alex/conf/templates/test-1/conf-notes.txt
You can try out the configuration with
TEMPLATECONF=/srv/work/alex/meta-alex/conf/templates/test-1 . /srv/work/alex/poky/oe-init-build-env build-try-test-1

The above command takes the config files from the currently active Build Directory under conf, replaces site-specific paths in bblayers.conf with ##OECORE##-relative paths, and copies the config files into a specified layer under a specified template name.

To use those saved templates as a starting point for a build, users should point to one of them with TEMPLATECONF environment variable:

TEMPLATECONF=/srv/work/alex/meta-alex/conf/templates/test-1 . /srv/work/alex/poky/oe-init-build-env build-try-test-1

The OpenEmbedded build system uses the environment variable TEMPLATECONF to locate the directory from which it gathers configuration information that ultimately ends up in the Build Directory conf directory.

If TEMPLATECONF is not set, the default value is obtained from .templateconf file that is read from the same directory as oe-init-build-env script. For the Poky reference distribution this would be:

TEMPLATECONF=${TEMPLATECONF:-meta-poky/conf/templates/default}

If you look at a configuration template directory, you will see the bblayers.conf.sample, local.conf.sample, and conf-notes.txt files. The build system uses these files to form the respective bblayers.conf file, local.conf file, and show users a note about the build they’re setting up when running the oe-init-build-env setup script. These can be edited further if needed to improve or change the build configurations available to the users.