poky/bitbake
Alexander Kanavin 941ac7d256 bitbake: parse/ast: add support for 'built-in' fragments
When reviewing proposed fragments to add settings for DISTRO and MACHINE,
RP noted that such fragments only add clutter and overhead, and there's
no need to maintain them as separate files.

Rather when bitbake sees 'fragmentvar/fragmentvalue' it can expand that into
FRAGMENTVAR = "fragmentvalue".

To achieve that, 'addfragments' directive is extended with a parameter
that sets the name of the variable that holds definitions of such
built-in fragments, for example like this:

"machine:MACHINE distro:DISTRO"

Then each enabled fragment name is matched against these definitions and the
respective variable is set, e.g. 'machine/qemuarm' would match
'machine:MACHINE' and result in MACHINE set to 'qemuarm'.

This happens before any fragment files are looked up on disk,
and no such lookup happens if there was a match, which should prevent
possible misuse of the feature. So the builtin fragment definition
is also an allowlist for them.

Please also see the patches for oe-core that show an application of the feature.

(Bitbake rev: 3b9d7bea915dc7f10e845854f1dae325743f9456)

Signed-off-by: Alexander Kanavin <alex@linutronix.de>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
2025-06-20 12:03:37 +01:00
..
bin bitbake: bitbake: Bump to version 2.15.0 2025-06-16 22:23:18 +01:00
contrib bitbake: contrib: vim: ftdetect: don't conflict with other filetypes 2025-03-03 21:38:57 +00:00
doc bitbake: parse/ast: add support for 'built-in' fragments 2025-06-20 12:03:37 +01:00
lib bitbake: parse/ast: add support for 'built-in' fragments 2025-06-20 12:03:37 +01:00
.b4-config bitbake: b4-config: Add basic support for b4 contribution workflow 2025-02-06 10:40:10 +00:00
.gitattributes
AUTHORS
ChangeLog
LICENSE
LICENSE.GPL-2.0-only
LICENSE.MIT
README bitbake: doc: README: simpler link to contributor guide 2024-02-10 14:13:51 +00:00
SECURITY.md bitbake: SECURITY.md: add file 2023-10-24 12:49:56 +01:00
toaster-requirements.txt bitbake: Update toaster-requirements to add django-log-viewer==1.1.7 2023-10-15 09:12:05 +01:00

Bitbake
=======

BitBake is a generic task execution engine that allows shell and Python tasks to be run
efficiently and in parallel while working within complex inter-task dependency constraints.
One of BitBake's main users, OpenEmbedded, takes this core and builds embedded Linux software
stacks using a task-oriented approach.

For information about Bitbake, see the OpenEmbedded website:
    https://www.openembedded.org/

Bitbake plain documentation can be found under the doc directory or its integrated
html version at the Yocto Project website:
    https://docs.yoctoproject.org

Bitbake requires Python version 3.8 or newer.

Contributing
------------

Please refer to our contributor guide here: https://docs.yoctoproject.org/contributor-guide/
for full details on how to submit changes.

As a quick guide, patches should be sent to bitbake-devel@lists.openembedded.org
The git command to do that would be:

    git send-email -M -1 --to bitbake-devel@lists.openembedded.org

If you're sending a patch related to the BitBake manual, make sure you copy
the Yocto Project documentation mailing list:

    git send-email -M -1 --to bitbake-devel@lists.openembedded.org --cc docs@lists.yoctoproject.org

Mailing list:

    https://lists.openembedded.org/g/bitbake-devel

Source code:

    https://git.openembedded.org/bitbake/

Testing
-------

Bitbake has a testsuite located in lib/bb/tests/ whichs aim to try and prevent regressions.
You can run this with "bitbake-selftest". In particular the fetcher is well covered since
it has so many corner cases. The datastore has many tests too. Testing with the testsuite is
recommended before submitting patches, particularly to the fetcher and datastore. We also
appreciate new test cases and may require them for more obscure issues.

To run the tests "zstd" and "git" must be installed.

The assumption is made that this testsuite is run from an initialized OpenEmbedded build
environment (i.e. `source oe-init-build-env` is used). If this is not the case, run the
testsuite as follows:

    export PATH=$(pwd)/bin:$PATH
    bin/bitbake-selftest

The testsuite can alternatively be executed using pytest, e.g. obtained from PyPI (in this
case, the PATH is configured automatically):

    pytest