From: Matt Corallo Date: Thu, 31 Dec 2020 00:47:32 +0000 (-0500) Subject: [bindings] Implement ReadableArgs mapping, try impl mapping for ()s X-Git-Tag: v0.0.13~37^2~8 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=56134a2bd123b75448536de5e945374e8b011f92;p=rust-lightning [bindings] Implement ReadableArgs mapping, try impl mapping for ()s This is most of the code to expose `ChannelManager`/`ChannelMonitor` deserialization in our C bindings, using the new infrastructure to map types in `maybe_convert_trait_impl` and passing generics in from the callsites. We also call `maybe_convert_trait_impl` for tuple types, as the `ChannelManager`/`ChannelMonitor` deserialization returns a `(BlockHash, T)` to indicate the block hash at which users need to start resyncing the chain. The final step to expose them is in the next commit. --- diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs index c197839c9..ffb70f920 100644 --- a/c-bindings-gen/src/main.rs +++ b/c-bindings-gen/src/main.rs @@ -59,8 +59,8 @@ fn convert_macro(w: &mut W, macro_path: &syn::Path, stream: & } /// Convert "impl trait_path for for_ty { .. }" for manually-mapped types (ie (de)serialization) -fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path, for_ty: &syn::Type, types: &mut TypeResolver) { - if let Some(t) = types.maybe_resolve_path(&trait_path, None) { +fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path, for_ty: &syn::Type, types: &mut TypeResolver, generics: &GenericTypes) { + if let Some(t) = types.maybe_resolve_path(&trait_path, Some(generics)) { let for_obj; let full_obj_path; let mut has_inner = false; @@ -68,13 +68,13 @@ fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path if let Some(ident) = p.path.get_ident() { for_obj = format!("{}", ident); full_obj_path = for_obj.clone(); - has_inner = types.c_type_has_inner_from_path(&types.resolve_path(&p.path, None)); + has_inner = types.c_type_has_inner_from_path(&types.resolve_path(&p.path, Some(generics))); } else { return; } } else { // We assume that anything that isn't a Path is somehow a generic that ends up in our // derived-types module. let mut for_obj_vec = Vec::new(); - types.write_c_type(&mut for_obj_vec, for_ty, None, false); + types.write_c_type(&mut for_obj_vec, for_ty, Some(generics), false); full_obj_path = String::from_utf8(for_obj_vec).unwrap(); assert!(full_obj_path.starts_with(TypeResolver::generated_container_path())); for_obj = full_obj_path[TypeResolver::generated_container_path().len() + 2..].into(); @@ -88,12 +88,12 @@ fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path let ref_type = syn::Type::Reference(syn::TypeReference { and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None, elem: Box::new(for_ty.clone()) }); - assert!(!types.write_from_c_conversion_new_var(w, &syn::Ident::new("obj", Span::call_site()), &ref_type, None)); + assert!(!types.write_from_c_conversion_new_var(w, &syn::Ident::new("obj", Span::call_site()), &ref_type, Some(generics))); write!(w, "\tcrate::c_types::serialize_obj(").unwrap(); - types.write_from_c_conversion_prefix(w, &ref_type, None); + types.write_from_c_conversion_prefix(w, &ref_type, Some(generics)); write!(w, "unsafe {{ &*obj }}").unwrap(); - types.write_from_c_conversion_suffix(w, &ref_type, None); + types.write_from_c_conversion_suffix(w, &ref_type, Some(generics)); writeln!(w, ")").unwrap(); writeln!(w, "}}").unwrap(); @@ -104,7 +104,7 @@ fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path writeln!(w, "}}").unwrap(); } }, - "util::ser::Readable" => { + "util::ser::Readable"|"util::ser::ReadableArgs" => { // Create the Result syn::Type let mut err_segs = syn::punctuated::Punctuated::new(); err_segs.push(syn::PathSegment { ident: syn::Ident::new("ln", Span::call_site()), arguments: syn::PathArguments::None }); @@ -128,17 +128,48 @@ fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path leading_colon: None, segments: res_segs } }); writeln!(w, "#[no_mangle]").unwrap(); - write!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice) -> ", for_obj).unwrap(); - types.write_c_type(w, &res_ty, None, false); + write!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice", for_obj).unwrap(); + + let mut arg_conv = Vec::new(); + if t == "util::ser::ReadableArgs" { + write!(w, ", arg: ").unwrap(); + assert!(trait_path.leading_colon.is_none()); + let args_seg = trait_path.segments.iter().last().unwrap(); + assert_eq!(format!("{}", args_seg.ident), "ReadableArgs"); + if let syn::PathArguments::AngleBracketed(args) = &args_seg.arguments { + assert_eq!(args.args.len(), 1); + if let syn::GenericArgument::Type(args_ty) = args.args.iter().next().unwrap() { + types.write_c_type(w, args_ty, Some(generics), false); + + assert!(!types.write_from_c_conversion_new_var(&mut arg_conv, &syn::Ident::new("arg", Span::call_site()), &args_ty, Some(generics))); + + write!(&mut arg_conv, "\tlet arg_conv = ").unwrap(); + types.write_from_c_conversion_prefix(&mut arg_conv, &args_ty, Some(generics)); + write!(&mut arg_conv, "arg").unwrap(); + types.write_from_c_conversion_suffix(&mut arg_conv, &args_ty, Some(generics)); + } else { unreachable!(); } + } else { unreachable!(); } + } + write!(w, ") -> ").unwrap(); + types.write_c_type(w, &res_ty, Some(generics), false); writeln!(w, " {{").unwrap(); - writeln!(w, "\tlet res = crate::c_types::deserialize_obj(ser);").unwrap(); + + if t == "util::ser::ReadableArgs" { + w.write(&arg_conv).unwrap(); + write!(w, ";\n\tlet res: ").unwrap(); + // At least in one case we need type annotations here, so provide them. + types.write_rust_type(w, Some(generics), &res_ty); + writeln!(w, " = crate::c_types::deserialize_obj_arg(ser, arg_conv);").unwrap(); + } else { + writeln!(w, "\tlet res = crate::c_types::deserialize_obj(ser);").unwrap(); + } write!(w, "\t").unwrap(); - if types.write_to_c_conversion_new_var(w, &syn::Ident::new("res", Span::call_site()), &res_ty, None, false) { + if types.write_to_c_conversion_new_var(w, &syn::Ident::new("res", Span::call_site()), &res_ty, Some(generics), false) { write!(w, "\n\t").unwrap(); } - types.write_to_c_conversion_inline_prefix(w, &res_ty, None, false); + types.write_to_c_conversion_inline_prefix(w, &res_ty, Some(generics), false); write!(w, "res").unwrap(); - types.write_to_c_conversion_inline_suffix(w, &res_ty, None, false); + types.write_to_c_conversion_inline_suffix(w, &res_ty, Some(generics), false); writeln!(w, "\n}}").unwrap(); }, _ => {}, @@ -675,6 +706,31 @@ fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct, /// /// A few non-crate Traits are hard-coded including Default. fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) { + if let syn::Type::Tuple(_) = &*i.self_ty { + if types.understood_c_type(&*i.self_ty, None) { + let mut gen_types = GenericTypes::new(); + if !gen_types.learn_generics(&i.generics, types) { + eprintln!("Not implementing anything for `impl (..)` due to not understood generics"); + return; + } + + if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); } + if let Some(trait_path) = i.trait_.as_ref() { + if trait_path.0.is_some() { unimplemented!(); } + if types.understood_c_path(&trait_path.1) { + eprintln!("Not implementing anything for `impl Trait for (..)` - we only support manual defines"); + return; + } else { + // Just do a manual implementation: + maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types); + } + } else { + eprintln!("Not implementing anything for plain `impl (..)` block - we only support `impl Trait for (..)` blocks"); + return; + } + } + return; + } if let &syn::Type::Path(ref p) = &*i.self_ty { if p.qself.is_some() { unimplemented!(); } if let Some(ident) = single_ident_generic_path_to_ident(&p.path) { @@ -896,12 +952,12 @@ fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut Typ }, "PartialEq" => {}, // If we have no generics, try a manual implementation: - _ if p.path.get_ident().is_some() => maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types), + _ if p.path.get_ident().is_some() => maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types), _ => {}, } } else if p.path.get_ident().is_some() { // If we have no generics, try a manual implementation: - maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types); + maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types); } } else { let declared_type = (*types.get_declared_type(&ident).unwrap()).clone(); diff --git a/lightning-c-bindings/src/c_types/mod.rs b/lightning-c-bindings/src/c_types/mod.rs index 20c49a6d9..dcb8d3078 100644 --- a/lightning-c-bindings/src/c_types/mod.rs +++ b/lightning-c-bindings/src/c_types/mod.rs @@ -225,6 +225,9 @@ pub(crate) fn serialize_obj(i: &I) -> derive pub(crate) fn deserialize_obj(s: u8slice) -> Result { I::read(&mut s.to_slice()) } +pub(crate) fn deserialize_obj_arg>(s: u8slice, args: A) -> Result { + I::read(&mut s.to_slice(), args) +} #[repr(C)] #[derive(Copy, Clone)]