Feature request: Customize pointer types

[tbodt]

I'd like to be able to customize the types of pointer types generated by bindgen. That is, the input:

struct foo {
    int *bar;
};

would produce the output:

struct foo {
    pub bar: CustomPointer<::std::os::raw::c_int>,
}

where CustomPointer is an arbitrary type path specified in configuration.

The idea here is the custom pointer type can be a safe transparent wrapper around an integer value, which can e.g. treat the pointer as belonging to another process and read it from there.

[emilio]

Not opposed to this, seems like a reasonable thing to want. Curious about your use case, can you customize the header? Introducing an annotation for this should be straight-forward. Adding some sort of configuration seems a bit more tricky because we need a way to target fields and such which I don't think we have atm.

[tbodt]

I prefer not to customize the header. This is being generated from linux uapi headers. I don't need a way to target things though, I want this to apply universally.

[emilio]

Ah, alright, then it should also be trivial. A patch that checks the context options here:

rust-bindgen/src/codegen/mod.rs

Line 3612 in c39c47c

TypeKind::Pointer(inner) | TypeKind::Reference(inner) => {

Or even here:

rust-bindgen/src/codegen/mod.rs

Line 351 in c39c47c

fn to_ptr(self, is_const: bool) -> proc_macro2::TokenStream {

Would do and should be straight-forward.