Incremental rpm image generation, the rootfs would be totally removed and
re-created in the second generation by default, but with
INC_RPM_IMAGE_GEN = "1", the rpm based rootfs would be kept, and will do
update(remove/add some pkgs) on it.
NOTE: This is not suggested when you want to create a productive rootfs
For example:
1) Add the follow config option to a conf file:
INC_RPM_IMAGE_GEN = "1"
2) bitbake core-image-sato
modify a package
bitbake core-image-sato
The rootfs would not be totally removed and re-created in the second
generation, it would be simply updated based on the "package".
Implatation:
1) Figure out the pkg which need to be removed or re-installed, then use
'rpm -e to remove the old one. Use the rpm's BUILDTIME to determine
which pkg has been rebuilt.
2) Figure out the pkg which is newly added, and use 'rpm -U' to install
it.
This only for the rpm based rootfs, the deb and ipk based rootfs would
be done later.
[YOCTO #1651]
Signed-off-by: Robert Yang <liezhi.yang@windriver.com>
