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extern crate proc_macro;
extern crate quote;
extern crate syn;
extern crate libc;
use proc_macro::TokenStream;
use quote::quote;
#[proc_macro_attribute]
pub fn function(_attr: TokenStream, item: TokenStream) -> TokenStream {
let input = syn::parse_macro_input!(item as syn::ItemFn);
match input.vis {
syn::Visibility::Public(_) => compose_func(&input, &input.vis),
_ => panic!("Exposed member must be public")
}
}
#[proc_macro_attribute]
pub fn enumeration(_attr: TokenStream, item: TokenStream) -> TokenStream {
let input = syn::parse_macro_input!(item as syn::ItemEnum);
match input.vis {
syn::Visibility::Public(_) => compose_enum(&input),
_ => panic!("Exposed member must be public")
}
}
fn compose_enum(input: &syn::ItemEnum) -> TokenStream {
let result = quote! {
#[repr(C)]
#[no_mangle]
#input
};
result.into()
}
fn compose_func(input: &syn::ItemFn, vis: &syn::Visibility) -> TokenStream {
let name = &input.ident;
let args = &input.decl.inputs;
let out = &input.decl.output;
let block = &input.block;
let out = match &out {
syn::ReturnType::Type(_, _) => out,
_ => panic!("Must specify return type on exposed functions")
};
let result = quote! {
#[no_mangle]
#vis extern fn #name(#args) #out {
#block
}
};
result.into()
}