use proc_macro2::Span;
use proc_macro_crate::{crate_name, FoundCrate};
use syn::{
parse::{Parse, ParseStream},
spanned::Spanned,
token, Error, Ident, Path,
};
mod keywords {
syn::custom_keyword!(Runtime);
syn::custom_keyword!(BlockExecutor);
syn::custom_keyword!(CheckInherents);
}
struct Input {
runtime: Path,
block_executor: Path,
check_inherents: Option<Path>,
}
impl Parse for Input {
fn parse(input: ParseStream) -> Result<Self, Error> {
let mut runtime = None;
let mut block_executor = None;
let mut check_inherents = None;
fn parse_inner<KW: Parse + Spanned>(
input: ParseStream,
result: &mut Option<Path>,
) -> Result<(), Error> {
let kw = input.parse::<KW>()?;
if result.is_none() {
input.parse::<token::Eq>()?;
*result = Some(input.parse::<Path>()?);
if input.peek(token::Comma) {
input.parse::<token::Comma>()?;
}
Ok(())
} else {
Err(Error::new(kw.span(), "Is only allowed to be passed once"))
}
}
while !input.is_empty() || runtime.is_none() || block_executor.is_none() {
let lookahead = input.lookahead1();
if lookahead.peek(keywords::Runtime) {
parse_inner::<keywords::Runtime>(input, &mut runtime)?;
} else if lookahead.peek(keywords::BlockExecutor) {
parse_inner::<keywords::BlockExecutor>(input, &mut block_executor)?;
} else if lookahead.peek(keywords::CheckInherents) {
parse_inner::<keywords::CheckInherents>(input, &mut check_inherents)?;
} else {
return Err(lookahead.error())
}
}
Ok(Self {
runtime: runtime.expect("Everything is parsed before; qed"),
block_executor: block_executor.expect("Everything is parsed before; qed"),
check_inherents,
})
}
}
fn crate_() -> Result<Ident, Error> {
match crate_name("cumulus-pallet-parachain-system") {
Ok(FoundCrate::Itself) =>
Ok(syn::Ident::new("cumulus_pallet_parachain_system", Span::call_site())),
Ok(FoundCrate::Name(name)) => Ok(Ident::new(&name, Span::call_site())),
Err(e) => Err(Error::new(Span::call_site(), e)),
}
}
#[proc_macro]
pub fn register_validate_block(input: proc_macro::TokenStream) -> proc_macro::TokenStream {
let Input { runtime, block_executor, check_inherents } = match syn::parse(input) {
Ok(t) => t,
Err(e) => return e.into_compile_error().into(),
};
let crate_ = match crate_() {
Ok(c) => c,
Err(e) => return e.into_compile_error().into(),
};
let check_inherents = match check_inherents {
Some(_check_inherents) => {
quote::quote! { #_check_inherents }
},
None => {
quote::quote! {
#crate_::DummyCheckInherents<<#runtime as #crate_::validate_block::GetRuntimeBlockType>::RuntimeBlock>
}
},
};
if cfg!(not(feature = "std")) {
quote::quote! {
#[doc(hidden)]
mod parachain_validate_block {
use super::*;
#[no_mangle]
unsafe fn validate_block(arguments: *mut u8, arguments_len: usize) -> u64 {
let args = #crate_::validate_block::Box::from_raw(
#crate_::validate_block::slice::from_raw_parts_mut(
arguments,
arguments_len,
)
);
let args = #crate_::validate_block::bytes::Bytes::from(args);
let params = #crate_::validate_block::decode_from_bytes::<
#crate_::validate_block::MemoryOptimizedValidationParams
>(args).expect("Invalid arguments to `validate_block`.");
let res = #crate_::validate_block::implementation::validate_block::<
<#runtime as #crate_::validate_block::GetRuntimeBlockType>::RuntimeBlock,
#block_executor,
#runtime,
#check_inherents,
>(params);
#crate_::validate_block::polkadot_parachain_primitives::write_result(&res)
}
}
}
} else {
quote::quote!()
}
.into()
}