On 25.02.21 06:08, vijaikumar....@gmail.com wrote:
>
>
> On Thursday, February 25, 2021 at 9:27:51 AM UTC+5:30
> vijaikumar....@gmail.com wrote:
>
> On Wed, Feb 24, 2021 at 5:43 PM Henning Schild
> <henning...@siemens.com> wrote:
> >
> > Am Tue, 23 Feb 2021 14:08:29 +0530
> > schrieb vijai kumar <vijaikumar....@gmail.com>:
> >
> > > On Sat, Feb 20, 2021 at 1:59 PM Henning Schild
> > > <henning...@siemens.com> wrote:
> > > >
> > > > Am Sat, 20 Feb 2021 01:27:19 +0530
> > > > schrieb Vijai Kumar K <Vijaikumar_...@mentor.com>:
> > > >
> > > > > /etc/os-release is a symlink to /usr/lib/os-release and
> belongs to
> > > > > the base-files package.
> > > > >
> > > > > ISAR has been modifying the /etc/os-release during
> postprocessing
> > > > > to inject custom data onto it.
> > > > >
> > > > > Since this file belongs to base-files, an update/reinstall
> of the
> > > > > package would overwrite the file with the one provided by
> > > > > base-files.
> > > >
> > > > To some degree such an update would be right to do so. The
> BUILD_ID
> > > > will for sure be invalidated, other custom fields might still be
> > > > valid though.
> > > >
> > > > > Instead of modifying the contents of /etc/os-release during
> > > > > post-processing, provide a modified base-files recipe in ISAR
> > > > > which provides the similar changes in os-release.
> > > >
> > > > I am beginning to wonder if we have to write certain bits to
> other
> > > > files. Bits that need to go into /etc/os-release could be
> appended
> > > > with a hook
> > > > See isar-disable-apt-cache, or we use the divert that Silvano
> > > > proposed.
> > >
> > > I have not used hooks before, but looks like it might help in our
> > > case.
> > >
> > > >
> > > > > Signed-off-by: Vijai Kumar K <Vijaikumar_...@mentor.com>
> > > > > ---
> > > > > .../recipes-core/images/isar-image-base.bb
> <http://isar-image-base.bb> | 2 +
> > > > > meta/classes/image-postproc-extension.bbclass | 40
> --------------
> > > > > meta/classes/image.bbclass | 20 -------
> > > > > meta/recipes-core/base-files/base-files.bb
> <http://base-files.bb> | 6 ++
> > > > > meta/recipes-core/base-files/base-files.inc | 55
> > > > > +++++++++++++++++++ 5 files changed, 63 insertions(+), 60
> > > > > deletions(-) create mode 100644
> > > > > meta/recipes-core/base-files/base-files.bb
> <http://base-files.bb> create mode 100644
> > > > > meta/recipes-core/base-files/base-files.inc
> > > > >
> > > > > diff --git
> a/meta-isar/recipes-core/images/isar-image-base.bb
> <http://isar-image-base.bb>
> > > > > b/meta-isar/recipes-core/images/isar-image-base.bb
> <http://isar-image-base.bb> index
> > > > > b381d85..4aa7e66 100644 ---
> > > > > a/meta-isar/recipes-core/images/isar-image-base.bb
> <http://isar-image-base.bb> +++
> > > > > b/meta-isar/recipes-core/images/isar-image-base.bb
> <http://isar-image-base.bb> @@ -11,3 +11,5
> > > > > @@ LIC_FILES_CHKSUM =
> > > > >
> "file://${LAYERDIR_core}/licenses/COPYING.GPLv2;md5=751419260 PV =
> > > > > "1.0" inherit image
> > > > > +
> > > > > +IMAGE_INSTALL += "base-files"
> > > > > diff --git a/meta/classes/image-postproc-extension.bbclass
> > > > > b/meta/classes/image-postproc-extension.bbclass index
> > > > > 3f00c21..22c6a95 100644 ---
> > > > > a/meta/classes/image-postproc-extension.bbclass +++
> > > > > b/meta/classes/image-postproc-extension.bbclass @@ -1,38
> +1,6 @@
> > > > > # This software is a part of ISAR.
> > > > > # Copyright (C) Siemens AG, 2019
> > > > >
> > > > > -update_etc_os_release() {
> > > > > - OS_RELEASE_BUILD_ID=""
> > > > > - OS_RELEASE_VARIANT=""
> > > > > - OS_RELEASE_VARIANT_VERSION=""
> > > > > - while true; do
> > > > > - case "$1" in
> > > > > - --build-id) OS_RELEASE_BUILD_ID=$2; shift ;;
> > > > > - --variant) OS_RELEASE_VARIANT=$2; shift ;;
> > > > > - --version) OS_RELEASE_VARIANT_VERSION=$2; shift ;;
> > > > > - -*) bbfatal "$0: invalid option specified: $1" ;;
> > > > > - *) break ;;
> > > > > - esac
> > > > > - shift
> > > > > - done
> > > > > -
> > > > > - if [ -n "${OS_RELEASE_BUILD_ID}" ]; then
> > > > > - sudo sed -i '/^BUILD_ID=.*/d'
> > > > > '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - echo "BUILD_ID=\"${OS_RELEASE_BUILD_ID}\"" | \
> > > > > - sudo tee -a '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - fi
> > > > > - if [ -n "${OS_RELEASE_VARIANT}" ]; then
> > > > > - sudo sed -i '/^VARIANT=.*/d'
> > > > > '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - echo "VARIANT=\"${OS_RELEASE_VARIANT}\"" | \
> > > > > - sudo tee -a '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - fi
> > > > > - if [ -n "${OS_RELEASE_VARIANT_VERSION}" ]; then
> > > > > - sudo sed -i '/^ISAR_IMAGE_VERSION=.*/d'
> > > > > '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - echo "VARIANT_VERSION=\"${PV}\"" | \
> > > > > - sudo tee -a '${IMAGE_ROOTFS}/etc/os-release'
> > > > > - fi
> > > > > -}
> > > >
> > > > This is in the image for a good reason, it can not be part of a
> > > > package, otherwise it would already be and we might not have that
> > > > evil postprocess feature.
> > > >
> > > > Try a run, append a package to IMAGE_PREINSTALL, build again
> > > >
> > > > I kind of bet that BUILD_ID will be wrong and not show your new
> > > > commit or "dirty"
> > >
> > > Yes, It is wrong.
> > >
> > > Since we definitely know that we are bringing in a variable
> > > that changes everytime when there is a change to the source
> code, we
> > > could very well do do_prepare_build[nostamp]="1".
> > >
> > > That with some changes should solve this problem.
> >
> > It will mean that every change will trigger a full reinstall of the
> > image, many changes do that, but it sounds bad.
> >
> > And the false-sharing between images and multiconfigs still remains.
> >
> > Try two images in one layer with differing DESCRIPTIONS and see what
> > happens. That would be the simple case without even thinking mc
>
> So basically os-release varies based on the image built. With a
> single package
> like this, it is no longer possible. At anypoint we could have only
> one version
> of the package.
>
>
> Basically we just considered each image to be a "derivative" . Which I
> don't suppose
> is the case, at least with upstream ISAR.
>  
>
>
> Then, again, it makes me wonder if os-release is an apt place for such
> information.
> We lose updatability with the other approach. We definitely leave one
> file (/etc/os-release or /usr/lib/os-release)
> outdated on a dist upgrade. 
>

So far, we did not consider os-release in package-based update scenarios
(likely because all our updates were partition based - which doesn't
mean package-based will not come one day as well). If we include
package-based updates, os-release should be updated by a package as well.

Our os-release modification (ISAR_RELEASE_CMD) is bound to an image. An
image is not a package, but we could make it depend on an image-specific
package carrying or generating that os-release data. That package should
definitely NOT be base-files. We need to divert that file and keep it
under our control. Obviously, if the user decides to do a an upgrade of
the Debian version on the device without pulling a new image version
package, things will really divert - but that is no reasonable use case
IMHO.

Jan

--
Siemens AG, T RDA IOT
Corporate Competence Center Embedded Linux