core-foundation-rs VS winapi-rs

Rust has RAII so you can have retain on 'clone' operations and release on drops, just like the native Rc/Arc types do.

This is, incidentally, how the servo bindings to core-foundation work (I prefer those bindings where there is overlap).

Servo bindings: https://github.com/servo/core-foundation-rs

Other crates of interest on this topic:

For Mac fans, the closest you'll have to this in OS-X is core-foundation-rs[1], by the servo team.

[1] https://github.com/servo/core-foundation-rs

Core-Foundation

Vtables are pretty solved as well. I do a lot of Windows COM interop. Using the `windows` crate, vtables for COM interfaces are relegated to an implementation detail - instead you simply implement a (typically safe!) trait:

https://microsoft.github.io/windows-docs-rs/doc/windows/Win3...

Which can then be converted to a refcounted smart pointer:

https://microsoft.github.io/windows-docs-rs/doc/windows/Win3...

All driven by win32 sdk parsing and metadata.

But suppose we want to roll our own, because we tend to prefer `winapi` but it lacks definition. That's not too terrible either:

• https://github.com/MaulingMonkey/thindx-xaudio2/blob/master/...

• https://github.com/MaulingMonkey/thindx-xaudio2/blob/master/...

• https://github.com/MaulingMonkey/thindx-xaudio2/blob/master/...

I could more heavily lean on my macros ala `windows`, but I went the route of manual control for better doc comments, more explicit control of thread safety traits to match the existing C++ codebase, etc.

Is there some pointer casting? Yes. Is it annoying or likely to be what breaks? No. What is annoying?

• Stacked borrows and narrowing spatial provenance ( https://github.com/retep998/winapi-rs/issues/1025 - this can be "solved" by sticking to pointers ala `windows`, or by choosing a different provenance model like rustc might be doing?)

• Guarding against panics unwinding over an FFI boundary. This is at least being worked on, but remains unfinished ( https://rust-lang.github.io/rfcs/2945-c-unwind-abi.html )

• Edge case ABI weirdness specific to C++ methods ( https://devblogs.microsoft.com/oldnewthing/20220113-00/?p=10... , https://github.com/retep998/winapi-rs/issues/523 )

Is winapi = { version = "0.3.9", features = ["winuser"] } in [target.'cfg(windows)'.dependencies]? All the missing symbols are functions in module winapi::um::wincrypt (see https://docs.rs/winapi/0.3.9/winapi/um/wincrypt/index.html#functions ) and the crate's Git repo at https://github.com/retep998/winapi-rs contains all the import libs and export defs for the corresponding DLLs in directory x86_64. As crypt32.dll ships with windows by default, I think this is all that would be needed for building on a windows PC.

The std library provides the type c_void for FFI, which is an enum with two variants. Some libraries have their own version, winapi for example defines c_void as an enum with no variants, making it identical to !. Finally, whenever the std needs a pointer with no particular type, they tend to reach for *const (), see ptr::to_raw_parts.

This would be a community driven project for now but I have high hopes considering we already had projects like winapi and Trantect/winapi-rs.

Can't you choose to control what OS APIs you use if you use crates such as libc and winapi, or just directly using extern "C" { ... }/extern "system" { ... }, or even inline assembly for syscalls with llvm_asm! or asm!?

Thank you! For SDL2 access, we're using custom bindings over the sdl2-sys crate, along with custom bindings for OpenGL and Vulkan access, and the winapi crate for Direct3D 11 access (as well as access to a few Windows APIs).

What is the difference between the winapi crate and the windows crate? Are they the same thing, and is one better than the other?

Turns out OpenGL and Vulkan sometimes behave weirdly on Windows machines (some OpenGL drivers use a huge amount of CPU power and create unexpected sync points; I also ran into this very weird driver crash while testing our Vulkan-powered version of Outer Wonders which is scary), so we implemented Direct3D 11 support using the winapi crate, which was much of a relief (D3D11 is an ideal rendering API when it comes to supporting Windows because it allows you target hardware with Windows versions going as far back as Vista, and from my experience, Direct3D drivers have a more consistent and reliable behavior). We didn't have to bring significant changes to our abstraction layer to add Direct3D 11 support.