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 76 77 78 79 80 81
#[macro_use]
extern crate syn;
use proc_macro::TokenStream;
use std::str::FromStr;
/// This attribute macro generates the boilerplate required to call into the
/// contract-specific logic from the entry-points to the Wasm module.
///
/// It should be added to the contract's init, handle, migrate and query implementations
/// like this:
/// ```
/// # use cosmwasm_std::{
/// # Storage, Api, Querier, DepsMut, Deps, entry_point, Env, StdError, MessageInfo,
/// # Response, QueryResponse,
/// # };
/// #
/// # type InstantiateMsg = ();
/// # type ExecuteMsg = ();
/// # type QueryMsg = ();
///
/// #[entry_point]
/// pub fn instantiate(
/// deps: DepsMut,
/// env: Env,
/// info: MessageInfo,
/// msg: InstantiateMsg,
/// ) -> Result<Response, StdError> {
/// # Ok(Default::default())
/// }
///
/// #[entry_point]
/// pub fn execute(
/// deps: DepsMut,
/// env: Env,
/// info: MessageInfo,
/// msg: ExecuteMsg,
/// ) -> Result<Response, StdError> {
/// # Ok(Default::default())
/// }
///
/// #[entry_point]
/// pub fn query(
/// deps: Deps,
/// env: Env,
/// msg: QueryMsg,
/// ) -> Result<QueryResponse, StdError> {
/// # Ok(Default::default())
/// }
/// ```
///
/// where `InstantiateMsg`, `ExecuteMsg`, and `QueryMsg` are contract defined
/// types that implement `DeserializeOwned + JsonSchema`.
#[proc_macro_attribute]
pub fn entry_point(_attr: TokenStream, mut item: TokenStream) -> TokenStream {
let cloned = item.clone();
let function = parse_macro_input!(cloned as syn::ItemFn);
let name = function.sig.ident.to_string();
// The first argument is `deps`, the rest is region pointers
let args = function.sig.inputs.len() - 1;
// E.g. "ptr0: u32, ptr1: u32, ptr2: u32, "
let typed_ptrs = (0..args).fold(String::new(), |acc, i| format!("{acc}ptr{i}: u32, "));
// E.g. "ptr0, ptr1, ptr2, "
let ptrs = (0..args).fold(String::new(), |acc, i| format!("{acc}ptr{i}, "));
let new_code = format!(
r##"
#[cfg(target_arch = "wasm32")]
mod __wasm_export_{name} {{ // new module to avoid conflict of function name
#[no_mangle]
extern "C" fn {name}({typed_ptrs}) -> u32 {{
cosmwasm_std::do_{name}(&super::{name}, {ptrs})
}}
}}
"##
);
let entry = TokenStream::from_str(&new_code).unwrap();
item.extend(entry);
item
}