In parallel builds where a list of image targets are provided the build
may produce binaries that are not part of the named set of targets but
are created by series dependencies. These implicitly created binaries
may be generated by multiple builds but are unused as our convention for
the ubuntu-cpc project is to only consume binaries from the explicitly
named image targets; this avoid overwriting the same object by multiple
parallel builds.
This patch adds support for a 'provides' keyword for series files. It can
be specified multiple times per series file. The field is used by the
make-hooks script to generate a list of output files created explicitly by
the named image targets. The list is saved to the "explicit_provides"
file in the hooks output directory. In the case of the "all" target
this list would be empty. This list is consumed by the "final.binary"
hook file.
This patch adds support for optional final.binary hooks in hooks.d/base
and/or hooks.d/extra. These final.binary hooks are always included as
the last hook(s) if either exist with the hook in "extra" running last.
The base/final.binary hook includes logic to parse the "explicit_provides"
file generated by the make-hooks script and remove any binary output not
explicitly specified.
Some series files named unnecessary dependencies, specifically
disk-image, to keep output of implicit artifacts consistent between
parallel builds. These unnecessary dependencies are removed in this
patch.
This patch currently only applies to the "ubuntu-cpc" project.
More and more logic has been going into the hook scripts to decide under which conditions they should run or not. As we are moving to parallelized builds of image sets, this will get even more complicated. Base hooks will have to know which image sets they belong to and modification of the dependency chain between scripts will become more complicated and prone to errors, as the number of image sets grows.
This patch introduces explicit ordering and dependency handling for scripts through the use of `series` files and an explicit syntax for dependency specification.
