From c044fff4227796e3a7d1c285a0875d26f58cdec1 Mon Sep 17 00:00:00 2001 From: alemi Date: Sat, 21 Sep 2024 17:52:20 +0200 Subject: [PATCH] chore: made a jni-toolbox wrapper crate --- Cargo.lock | 9 ++- Cargo.toml | 14 ++--- src/lib.rs | 160 ++--------------------------------------------------- 3 files changed, 18 insertions(+), 165 deletions(-) diff --git a/Cargo.lock b/Cargo.lock index 5ea6b8a..bec4029 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -3,7 +3,14 @@ version = 3 [[package]] -name = "jni-macro" +name = "jni-toolbox" +version = "0.1.0" +dependencies = [ + "jni-toolbox-macro", +] + +[[package]] +name = "jni-toolbox-macro" version = "0.1.0" dependencies = [ "proc-macro2", diff --git a/Cargo.toml b/Cargo.toml index 5297d93..a073887 100644 --- a/Cargo.toml +++ b/Cargo.toml @@ -1,6 +1,9 @@ +[workspace] +members = ["macro"] + [package] -name = "jni-macro" -description = "proc macro to automate making JNI extern functions" +name = "jni-toolbox" +description = "tools to make writing JNI native functions less tiresome" repository = "https://github.com/hexedtech/jni-macro" authors = [ "alemi " @@ -9,10 +12,5 @@ license = "GPL-3.0-only" version = "0.1.0" edition = "2021" -[lib] -proc-macro = true - [dependencies] -syn = {version = "2.0", features = ["full"]} -quote = "1.0" -proc-macro2 = "1.0" +jni-toolbox-macro = { path = "./macro" } diff --git a/src/lib.rs b/src/lib.rs index 98c10c3..9fe78bf 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -1,157 +1,5 @@ -#[proc_macro_attribute] -pub fn jni( - attrs: proc_macro::TokenStream, - input: proc_macro::TokenStream, -) -> proc_macro::TokenStream { - generate_jni_wrapper( - syn::parse_macro_input!(attrs), - syn::parse_macro_input!(input), - ) - .unwrap() - .into() -} - - - - -use proc_macro2::{Span, TokenStream, TokenTree}; -use quote::TokenStreamExt; -use syn::{FnArg, Item, ReturnType, Type}; - -fn generate_jni_wrapper(attrs: TokenStream, input: TokenStream) -> Result { - let mut out = TokenStream::new(); - - let Item::Fn(fn_item) = syn::parse2(input.clone())? else { - return Err(syn::Error::new(Span::call_site(), "#[jni] is only supported on functions")); - }; - - let mut what_next = WhatNext::Nothing; - - let mut package = None; - let mut clazz = None; - - for attr in attrs { - match what_next { - WhatNext::Nothing => { - if let TokenTree::Ident(ref i) = attr { - match i.to_string().as_ref() { - "package" => what_next = WhatNext::Package, - "class" => what_next = WhatNext::Class, - _ => return Err(syn::Error::new(Span::call_site(), "unexpected attribute on macro: {attr}")), - } - } - }, - WhatNext::Class => { - if let TokenTree::Literal(i) = attr { - let raw = i.to_string().replace('"', ""); - clazz = Some(syn::Ident::new(&raw, Span::call_site())); - what_next = WhatNext::Nothing; - } - }, - WhatNext::Package => { - if let TokenTree::Literal(i) = attr { - let raw = i.to_string().replace('"', "").replace(".", "_"); - package = Some(syn::Ident::new(&raw, Span::call_site())); - what_next = WhatNext::Nothing; - } - }, - } - } - - let Some(package) = package else { return Err(syn::Error::new(Span::call_site(), "missing attribute 'package'")) }; - let Some(clazz) = clazz else { return Err(syn::Error::new(Span::call_site(), "missing attribute 'class'")) }; - - let (could_error, ret_type) = match fn_item.sig.output { - syn::ReturnType::Default => (false, fn_item.sig.output), - syn::ReturnType::Type(_tok, ty) => match *ty { - syn::Type::Path(ref path) => { - let Some(last) = path.path.segments.last() else { - return Err(syn::Error::new(Span::call_site(), "empty Result type is not valid")); - }; - - // TODO this is terrible, macro returns a function and we call it?? there must be a - // better way!!! - let mut out = ( - false, - ReturnType::Type(syn::Token![->](Span::call_site()), Box::new(Type::Path(path.clone()))) - ); - - if last.ident == "Result" { - match &last.arguments { - syn::PathArguments::None => return Err(syn::Error::new(Span::call_site(), "Result without generics is not valid")), - syn::PathArguments::Parenthesized(_) => return Err(syn::Error::new(Span::call_site(), "Parenthesized Result is not valid")), - syn::PathArguments::AngleBracketed(ref generics) => for generic in generics.args.iter() { - match generic { - syn::GenericArgument::Lifetime(_) => continue, - syn::GenericArgument::Type(ty) => { - out = (true, ReturnType::Type(syn::Token![->](Span::call_site()), Box::new(ty.clone()))); - break; - }, - _ => return Err(syn::Error::new(Span::call_site(), "unexpected type in Result")), - } - } - } - } - - out - }, - _ => return Err(syn::Error::new(Span::call_site(), "unsupported return type")), - }, - }; - - - let mut incoming = TokenStream::new(); - let mut forwarding = TokenStream::new(); - - for arg in fn_item.sig.inputs { - let FnArg::Typed(ty) = arg else { - return Err(syn::Error::new(Span::call_site(), "#[jni] macro doesn't work on methods")); - }; - incoming.append_all(quote::quote!( #ty , )); - let pat = ty.pat; - forwarding.append_all(quote::quote!( #pat , )); - } - - let name = fn_item.sig.ident.to_string(); - let name_jni = name.replace("_", "_1"); - let fn_name_inner = syn::Ident::new(&name, Span::call_site()); - let fn_name = syn::Ident::new(&format!("Java_{package}_{clazz}_{name_jni}"), Span::call_site()); - - let Some(env_ident) = forwarding.clone().into_iter().next() else { - return Err(syn::Error::new(Span::call_site(), "missing JNIEnv argument")); - }; - - let wrapped = if could_error { - quote::quote! { - #[no_mangle] - pub extern "system" fn #fn_name<'local>(#incoming) #ret_type { - match #fn_name_inner(#forwarding) { - Ok(x) => x, - Err(e) => { - #env_ident - .throw_new("java/lang/RuntimeException", format!("{e:?}")) - .expect("failed throwing Java exception from native call"); - return 0; - } - } - } - } - } else { - quote::quote! { - #[no_mangle] - pub extern "system" fn #fn_name<'local>(#incoming) #ret_type { - #fn_name_inner(#forwarding) - } - } - }; - - out.append_all(input); - out.append_all(wrapped); - Ok(out) -} - -enum WhatNext { - Nothing, - Package, - Class, +pub use jni_toolbox_macro::jni; + +pub trait JniToolboxError: std::error::Error { + fn jclass(&self) -> String; }