I am currently looking for the best way to configure existing Yocto recipes for my use case. For example the MySQL server of mariadb – part of the meta-oe layer.
I “activate” PACKAGECONFIG variables using .bbappend files. However, mariadb also has a configuration file (as CONFFILES) my.cnf in the recipe. How do I sensibly change the settings there?
- Can I overwrite
CONFFILES? Do I overwrite the file in my recipe, or in a.bbappendfile? - Do I patch the file?
- Do I put my own configuration file in
/etc/my.cnf.d/“next to it” and try to overwrite the options?
Of course I don’t want to change the original sources of the recipe to minimize the effort for updates.
I have found a lot of good instructions and documentation on how to create my own layers and recipes, but nothing that describes how I can best adapt existing recipes to my needs.
my.cnf already exists in SRC_URI of the original mariadb.inc file of meta-oe.
You just need to trick BitBake to search in your custom layer before reaching the actual meta-oe‘s mariadb recipe files.
Your custom layer should have:
recipes-support/
└── mysql
├── files
│ └── my.cnf
└── mariadb_%.bbappend
Then, in mariadb_%.bbappend just add:
FILESEXTRAPATHS:prepend := "${THISDIR}/files:"
Now, the original mariadb recipe (NB: by original I mean the final recipe after expanding all bbappends) will look for the file://my.cnf file using FILESEXTRAPATHS, and since you have prepended your custom path, it will find it there first.
NOTE: You don’t have to add my.cnf to SRC_URI again in your bbappend.