Do not add architecture to system packages by default, only when cross-compiling

[czoido]

Changelog: Feature: Do not add architecture to system packages by default, only when cross-compiling.
Docs: omit

The most common situation when installing system packages is that you don't use the architecture in the package name unless you are cross-compiling, so this defaults to that behaviour.
Also it's testing how to install archless packages even with cross-compilation, but that's something we probably want to change as the code would look a bit ugly. You can workaround that with an empty dictionary as arch_names in classes that accept the argument:

Apt(self).install(["libudev-dev"], update=True, check=True)
Apt(self, arch_names={}).install(["archless-package"], update=True, check=True)

Closes: #12320

[ericLemanissier]

I don't think this closes #12320, because the situation stays the same during cross compilation: for a given recipe either:

• all system packages have an arch suffix (if the recipe has an arch setting) or
• no system package has an arch suffix (if the recipe does not have an arch setting)

To fix the issue, we would need to have a method which installs the system packages it receives as argument, with noarch/all/any architecture suffix, depending on the package manager.
Just to be clear, there is no need for this feature currently in CCI. The offending case in CCI (xorg/system) was solved by removing all the arch-less system packages from xorg/system, and putting them in a dedicated recipe without arch setting

[czoido]

I don't think this closes #12320, because the situation stays the same during cross compilation: for a given recipe either:

• all system packages have an arch suffix (if the recipe has an arch setting) or
• no system package has an arch suffix (if the recipe does not have an arch setting)

To fix the issue, we would need to have a method which installs the system packages it receives as argument, with noarch/all/any architecture suffix, depending on the package manager. Just to be clear, there is no need for this feature currently in CCI. The offending case in CCI (xorg/system) was solved by removing all the arch-less system packages from xorg/system, and putting them in a dedicated recipe without arch setting

Hi @ericLemanissier, thanks for the comments. The intention of this PR is to:

• Change the default when invoking system package managers and don't add the architecture to the package names for the most common case that is not cross-compiling. As you say this would not close the issue.
• Provide a way of forcing installing packages without the architecture appended to the package name even if you are cross-compiling. This is not yet covered in the PR with a solution, I commented above that this can be workarounded with something like this:

Apt(self, arch_names={}).install(["archless-package"], update=True, check=True)

Passing arch_names as an empty dictionary in the constructor will make that the name resolution skips adding the architecture for all cases (cross-compiling and not). But that is ugly and probably we want to pass a new argument to cover this case. That workaround I think would close #12320 as then you also could mix archless packages with packages with arch in the same recipe without having to write a new recipe for the archless ones which I think would be more convenient. Am I missing something and maybe this would not be enough to cover the case?

Thanks a lot.

[jcar87]

Looks like a good default with the possibility of adding fine-grained control in the future 👍