File size: 2,650 Bytes
b98ffbb |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 |
use proc_macro::TokenStream;
use proc_macro2::TokenStream as TokenStream2;
use quote::quote;
extern crate proc_macro;
#[proc_macro]
pub fn register_operator(item: TokenStream) -> TokenStream {
// convert from `TokenStream` to `TokenStream2`, which is used by the
// `syn` crate
let item = TokenStream2::from(item);
// generate the dora wrapper functions
let generated = register_operator_impl(&item).unwrap_or_else(|err| err.to_compile_error());
// output the generated functions
let tokens = quote! {
#generated
};
// convert the type back from `TokenStream2` to `TokenStream`
tokens.into()
}
/// Generates the wrapper functions for the annotated function.
fn register_operator_impl(item: &TokenStream2) -> syn::Result<TokenStream2> {
// parse the type given to the `register_operator` macro
let operator_ty: syn::TypePath = syn::parse2(item.clone())
.map_err(|e| syn::Error::new(e.span(), "expected type as argument"))?;
let init = quote! {
#[no_mangle]
pub unsafe extern "C" fn dora_init_operator() -> dora_operator_api::types::DoraInitResult {
dora_operator_api::raw::dora_init_operator::<#operator_ty>()
}
const _DORA_INIT_OPERATOR: dora_operator_api::types::DoraInitOperator = dora_operator_api::types::DoraInitOperator {
init_operator: dora_init_operator,
};
};
let drop = quote! {
#[no_mangle]
pub unsafe extern "C" fn dora_drop_operator(operator_context: *mut std::ffi::c_void)
-> dora_operator_api::types::DoraResult
{
dora_operator_api::raw::dora_drop_operator::<#operator_ty>(operator_context)
}
const _DORA_DROP_OPERATOR: dora_operator_api::types::DoraDropOperator = dora_operator_api::types::DoraDropOperator {
drop_operator: dora_drop_operator,
};
};
let on_event = quote! {
#[no_mangle]
pub unsafe extern "C" fn dora_on_event(
event: &mut dora_operator_api::types::RawEvent,
send_output: &dora_operator_api::types::SendOutput,
operator_context: *mut std::ffi::c_void,
) -> dora_operator_api::types::OnEventResult {
dora_operator_api::raw::dora_on_event::<#operator_ty>(
event, send_output, operator_context
)
}
const _DORA_ON_EVENT: dora_operator_api::types::DoraOnEvent = dora_operator_api::types::DoraOnEvent {
on_event: dora_operator_api::types::OnEventFn(dora_on_event),
};
};
Ok(quote! {
#init
#drop
#on_event
})
}
|