cglue VS cbindgen

Shameless plug - you may want to check out cglue, which lets you mix and match rust versions, and even implement plugins in other languages like C++: https://github.com/h33p/cglue

You can grab CGlue from my GitHub.

I honestly wouldn't say that much has changed during this year. I do see some progress on new libraries like xlang_abi, safer_ffi or cglue, but it's still too early to know, and existing ones like abi_stable move quite slowly.

You might wanna take a look at cglue: https://github.com/h33p/cglue

Importing Rust is the same process as you'd use to import a C library, but there's a lot of people actively invested in this area so there's likely already automated tooling of some sort. Google uses https://cxx.rs for automating C++ bindings to Rust libraries, and lately there's been experiments like cglue to automate C bindings.

I'm proud to announce one final CGlue release for this year, the highlight being ability to use layout_checks feature on non-git builds!

I have just added pre-generated headers, they are now on the repo. Yup, certainly not the cleanest, some whitespaces need fixing, but it wasn't the highest priority as it didn't affect functionality.

Depending on how big your API surface is (and how trait heavy it is), you may want to look into [shameless_plug] automatically generating it with cglue. That's what we did for memflow. [/shameless_plug] It's goals are not much different from abi_stable (in fact, rather a small subset of it focused on traits), but does create C-compatible code.

It seems like we are trying to solve roughly the same problems when it comes to loading plugins and keeping it all ABI safe. Might be worth checking out CGlue (full disclosure: it's my project). While I do not have async trait support, it would be a really interesting challenge to tackle. The ultimate goal for the project is to be a dead simple code generator that would even allow to write plugins in C/C++, and I currently have sweeping changes underway to get it there.

Golang uses cgo to communicate with external C libraries and Rust uses FFI (Foreign function interfaces) to export C functions. Additionally, a library for automatically generating bindings can be used to generate the header files (.h). In our case, we'll only be exporting two C functions, so using cbindgen is overkill but we'll use it regardless because why not?  Firstly, we'll write the rust functions we want to export. We'll start by creating a new rust library:

[1]: https://github.com/mozilla/cbindgen

As a 2-step approach, you could also probably use https://github.com/mozilla/cbindgen and then Nim's native C FFI.

The tooling for the first kind -- calling Rust from another language -- is a bit less developed, and tends to rely on code generation that doesn't necessarily produce a natural C API. cbindgen, uniffi, cxx, and Diplomat all take this course.

There's also cbindgen for automating the generation of C headers once you've got your code in the right shape and you'll also want to read the Rustonomicon.

You can backport Rust standard library to C using https://github.com/eqrion/cbindgen .

Later we'll see what cbindgen essentially does is receive a configuration and a Rust library and then spit out a C header (.h) file. One might think that what cbindgen is doing might not be that special and can be done by hand. In which some cases that might be true if the project is simple enough. Though additionally as the cbindgen documentation states:

Fuck it, I'll take the bait. Rust allows for amazing C interop by allowing for exporting of C types as a dynamic library, like C. Unlike C, this still allows for Rust's advanced checking at compile time. librsvg is one such library that is being used in the GTK ecosystem that is also almost completely Rust. You can use tools like cbindgen to generate C bindings.

Or alternatively cbindgen to create the header file from the Rust source.

The easiest way to obtain the headers for the rust code is to use the cbingen library.