Windows: improve compatibility to build for UWP / Xbox

[thexai]

Feature or enhancement

Proposal:

• Add alternative UWP API functionality when available.
• Modernize the Windows code when there are alternatives that are also compatible with UWP.
• Add additional guards for Windows code that not builds for UWP.

The final goal is able to build for Xbox and reduce the patches required in Kodi --> Upstream some generic UWP patches here.

I propose upload small patches geared towards specific targets and always keeping current Windows functionality untouched.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-152433: Windows: use GetFileSizeEx instead of GetFileSize #152383
• gh-152433: Windows: enable mmapmodule for UWP #152473
• gh-152433: Windows: allow build prim.c for UWP #152477
• gh-152433: Windows: implement os.cpu_count() for UWP #152479

[picnixz]

cc @zooba @chris-eibl

[chris-eibl]

Hm, this first PR lgtm and no objections if the following ones are similar.

Adding @maxbachmann for visibility, who did similar Xbox PRs in the past.

[thexai]

The first one was extreme easy, there will be more complicated ones... but that's the idea :)

I believe some previous work was for the MS_WINDOWS_GAMES partition, but in my case I'm going to focus on the MS_WINDOWS_APP partition (Xbox Apps, not Games).

One thing that will complicate the patches quite a bit is that MS_WINDOWS_APP is defined for both Desktop and UWP and it creates a lot of complication and confusion in the #ifdef blocks, perhaps at some point we will have to decide whether to change this, but for the moment I'm going to try to avoid it.

In my private patches these definitions are exclusive but this requires modifications for the main branch.

For reference:
https://github.com/thexai/cpython/blob/6e8b0fc79f676d869a14370b11f57358d7a1621a/PC/pyconfig.h#L91-L97

And full Kodi patches (branch 3.14): https://github.com/thexai/cpython/tree/kodi/3.14.6

[maxbachmann]

Yes my previous work was for xbox games. We are currently on 3.13 with all our patches for the xbox support upstreamed.
However we don't build some of the "freestanding" modules that we don't use -> not sure they ever compiled. For other app partitions I didn't do any testing back then.