Read and write chunks of memory for CString

[nalenz-objectbox]

Currently, writing strings to and reading strings from memory is done character by character. Try to find a more efficient method to do that.

Is mostly related to CString (#7), but also memory chunks in general.

[vaind]

Dart FFI homepage links the following example:

Even though it still iterates, it looks less cumbersome than the current solution so maybe we could switch to that if there's no more efficient solution (consider opening an issue on dart github).

[Buggaboo]

I tried looking for a way to read a C (contiguous?) memory block into a dart buffer(ish) type, but I haven't seen an appropiate ffi function for that. Reading and writing strings char by char does cost unnecessary cycles...

[vaind]

I think this dart issue covers our use case dart-lang/sdk#35762

[vaind]

And there's actually a new FFI utility package by the core team that could help us
https://github.com/dart-lang/ffi - https://pub.dev/packages/ffi

Utf8::fromUtf8 and Utf8::toUtf8 seem like a way to go. Ideally, we would remove our CString class completely, import the ffi package and use those functions.

@Buggaboo would you be willing to give it a shot?

[Buggaboo]

I'm on it

[vaind]

Thanks @Buggaboo for tackling this 🥇