nix-store-c: `std::string_view` exposed as `const * char` in `nix_store_parse_path`

[jsoo1]

Describe the bug

parseStorePath takes a std::string_view, but the C external api exposes a const * char. Unless I'm missing something this effectively means that the C side has to re-implement a C++ std library type to correctly parse a store path.

• https://github.com/NixOS/nix/blob/64000481168d1da9d2519f055dd1fdee22275c21/src/libstore-c/nix_api_store.cc#L92
• https://github.com/NixOS/nix/blob/64000481168d1da9d2519f055dd1fdee22275c21/src/libstore/path.cc#L78

I don't know what standards we want to have for C->C++ strings but I bet a * char + length encoding would work.

Expected behavior

There should be a C-encoded means of passing strings from C->C++.

Metadata

$ pkg-config --print-provides nix-store-c
nix-store-c = 2.24.10

Checklist

• [X] checked latest Nix manual (source)
• [X] checked open bug issues and pull requests for possible duplicates

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[jsoo1]

Well, must be a me problem :shrug: .