[yocto] Check IMAGE_FEATURES content in recipe

[Alexander Kanavin]

On 05/10/2018 11:59 AM, Piotr Piwko wrote:
>     For 'read-only-rootfs' image feature, tweaks are done in functions
>     executed after generating rootfs.
>     meta/classes/rootfs-postcommands.bbclass:ROOTFS_POSTPROCESS_COMMAND
>     += '${@bb.utils.contains("IMAGE_FEATURES", "read-only-rootfs",
>     "read_only_rootfs_hook; ", "",d)}'
> 
>     Can you use a similar approach to solve your problem?
> 
> 
> Unfortunately, I can not. I would like to make a pkg_postinst() function 
> of my package dependent on the rootfs mount mode. It should be different 
> if the rootfs is going to be mounted as read-only.

You should be able to move the contents of the pkg_postinst to the hook. 
Actually two hooks: one for read only rootfs, another for read-write. 
Add this to your image recipe:

ROOTFS_POSTPROCESS_COMMAND += '${@bb.utils.contains("IMAGE_FEATURES", 
"read-only-rootfs", "piotrs_ro_rootfs_hook; ", "piotrs_rw_rootfs_hook; 
",d)}'


and implement the hook functions accordingly. By the time the hooks are 
executed, the package is already installed, so you can access its files 
as needed.

Alex