This change moves almost everything in the `upb/` directory up one level, so
that for example `upb/upb/generated_code_support.h` becomes just
`upb/generated_code_support.h`. The only exceptions I made to this were that I
left `upb/cmake` and `upb/BUILD` where they are, mostly because that avoids
conflict with other files and the current locations seem reasonable for now.
The `python/` directory is a little bit of a challenge because we had to merge
the existing directory there with `upb/python/`. I made `upb/python/BUILD` into
the BUILD file for the merged directory, and it effectively loads the contents
of the other BUILD file via `python/build_targets.bzl`, but I plan to clean
this up soon.
PiperOrigin-RevId: 568651768
1. getter function to access the upb_Map corresponding to a map proto field
2. conversion function to get a Go map from a upb_Map. The conversion function uses generics, so it must be a standalone function independent of `MessageAccessor`.
Accessing map fields is not as efficient as accessing other proto field types, because of two reasons:
- we need to make a copy of map values in Go, since the memory representations are different in UPB C
- we need to call C functions from Go, because the upb_Map struct fields are not exported and we can't access the bits directly, causing performance overhead
Luckily the map fields can be quite rare, so the performance overhead should not be too significant overall.
PiperOrigin-RevId: 559191359
Remove array.h and map.h as hdrs from :collections_internal
Remove alloc.h and arena.h as hdrs from :mem_internal (and add them to :mem)
Remove common.h and decode.h and encode.h as hdrs from :wire_internal
Lock down the visibility of :wire_internal to upb-only
Merge :mini_descriptor_encode_internal into :mini_descriptor_internal
PiperOrigin-RevId: 558235138
Eric Salo
Protobuf Team Bot
Adam Cozzette
Hong Shin