bitbake-setup: add the proof of concept implementationmaster-next

For the rationale and design guidelines please see this message:
https://lists.openembedded.org/g/openembedded-architecture/message/1913

Left out for now but will be done later:
- config fragment support
- tests
- documentation
- official configuration repository

1. If you don't know where to start, list available configurations, and pick one:

===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup list
Available configurations:
poky-alex	Poky reference distribution, with alex fixes
poky-kirkstone	Poky reference distribution, kirkstone long term support release (supported until April 2026)
===

2. Then build is initialized this way:
===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup init poky-alex
Initializing build in /home/alex/builds/poky-alex

Run /home/alex/builds/poky-alex/build/build.sh to build using this configuration.
===

Note: 'init' sub-command can also take a path or a URL with a configuration file directly.
You can see how those files look like here:
https://github.com/kanavin/bitbake-setup-configurations

3. The above message refers to a one-liner shell script that would build the targets
specified in the chosen configuration:
===
alex@Zen2:/srv/work/alex/bitbake$ cat /home/alex/builds/poky-alex/build/build.sh
. /home/alex/builds/poky-alex/build/init-build-env && bitbake core-image-minimal
===

4. To check if the build configuration needs to be updated, run:
===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup status ~/builds/poky-alex/
Configuration has not changed.
===

If the configuration has changed, you will see the difference:
===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup status ~/builds/poky-alex/
 Top level configuration has changed:
 --- /home/alex/builds/poky-alex/config/poky-alex.conf.json	2024-04-18 13:42:54.312460823 +0200
 +++ /home/alex/builds/poky-alex/config-tmp-b413az6s/poky-alex.conf.json	2024-04-18 13:50:42.635433203 +0200
 @@ -7,7 +7,7 @@
                          "uri": "git://git.yoctoproject.org/poky-contrib"
                      }
                  },
 -                "rev": "akanavin/sstate-for-all"
 +                "rev": "akanavin/sstate-for-all-and-everyone"
              },
              "path": "poky"
          }
===

If the configuration has not changed, but layer revisions referred to it have (for example
if the configuration specifies a tip of a branch), you will see that too:
===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup status ~/builds/poky-alex/
Layer repository git://git.yoctoproject.org/poky-contrib checked out into /home/alex/builds/poky-alex/layers/poky updated revision akanavin/sstate-for-all from 6b842ba55f996b27c900e3de78ceac8cb3b1c492 to aeb73e29379fe6007a8adc8d94c1ac18a93e68de
===

5. If the configuration has changed, you can bring it in sync with:
===
alex@Zen2:/srv/work/alex/bitbake$ bin/bitbake-setup update ~/builds/poky-alex/
Layer repository git://git.yoctoproject.org/poky-contrib checked out into /home/alex/builds/poky-alex/layers/poky updated revision akanavin/sstate-for-all from 6b842ba55f996b27c900e3de78ceac8cb3b1c492 to aeb73e29379fe6007a8adc8d94c1ac18a93e68de
... (skip git output)
Existing build directory renamed to /home/alex/builds/poky-alex/build-backup.20240418135458

Run /home/alex/builds/poky-alex/build/build.sh to build using this configuration.
===

Note that it will also rename the existing build directory, and print changes
in bitbake configuration (diff of content of build/conf/) if that has changed. I can't
at the moment think of anything more clever that is also not much more brittle or complex
to implement, but open to suggestions.

6. To make it easier to review the code, please also review the data it's operating on:
===
alex@Zen2:/srv/work/alex/bitbake$ ls ~/.bitbake-setup/
cache  configurations  downloads
alex@Zen2:/srv/work/alex/bitbake$ ls ~/builds/poky-alex/
build  build-backup.20240418135458  config  config-upstream.json  layers
===

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

0 files changed, 0 insertions, 0 deletions