feat: add __network/html-crawl-parse, __wasm/wasmtime-serde-demo

__wasm/wasmtime-serde-demo/crates/host_macro/src/lib.rs

@@ -0,0 +1,70 @@
+//! Simple library for serializing complex types to the wasmtime runtime using serde
+
+use proc_macro::TokenStream;
+use quote::{format_ident, quote};
+use syn::{parse_macro_input, ItemFn};
+
+struct FnHost {
+	functions: Vec<syn::Ident>,
+}
+
+impl syn::parse::Parse for FnHost {
+	fn parse(input: syn::parse::ParseStream) -> syn::parse::Result<Self> {
+		let mut functions = vec![];
+		let mut end = false;
+		while let Ok(f) = input.parse::<syn::Ident>() {
+			if end {
+				panic!("comma")
+			}
+			functions.push(f);
+			end = input.parse::<syn::Token![,]>().is_err();
+		}
+		Ok(Self { functions })
+	}
+}
+
+#[proc_macro]
+pub fn host_funcs(input: TokenStream) -> TokenStream {
+	let input = parse_macro_input!(input as FnHost);
+	let mut list = quote!();
+	let len = input.functions.len();
+	for name in input.functions {
+		let name = format_ident!("_wasm_host_{}", name);
+		let str_name: proc_macro2::TokenStream = format!(r#""{name}""#).parse().unwrap();
+		list = quote!(#list  (#str_name, #name),);
+	}
+	quote!({
+		const HOST_FUNC:[(&str, fn(&[u8]) -> Vec<u8>);#len] = [#list];
+		&HOST_FUNC
+	})
+	.into()
+}
+
+#[proc_macro_attribute]
+pub fn export_fn(_attr: TokenStream, item: TokenStream) -> TokenStream {
+	let data = parse_macro_input!(item as ItemFn);
+	let name = &data.sig.ident;
+	let extern_name = format_ident!("_wasm_host_{}", name);
+	let gen = {
+		let mut argument_types = quote!();
+		let mut call = quote!();
+		for (i, arg) in data.sig.inputs.iter().enumerate() {
+			let i = syn::Index::from(i);
+			call = quote!(#call message.#i,);
+			if let syn::FnArg::Typed(t) = arg {
+				let ty = &t.ty;
+				argument_types = quote!(#argument_types #ty,);
+			} else {
+				panic!();
+			}
+		}
+		argument_types = quote! { (#argument_types) };
+		quote! {
+			fn #extern_name(value: &[u8]) -> Vec<u8> {
+				let message:#argument_types = wasmtime_serde_host::deserialize(value).unwrap();
+				wasmtime_serde_host::serialize(&#name(#call)).unwrap()
+			}
+		}
+	};
+	quote!(#gen #data).into()
+}