From: Matt Corallo Date: Tue, 12 May 2020 18:49:29 +0000 (-0400) Subject: Add tool to read a Rust crate and generate C-compatible wrappers X-Git-Tag: v0.0.12~30^2~10 X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=48e8678a9a63319c87978b96a39b5848db757075;p=rust-lightning Add tool to read a Rust crate and generate C-compatible wrappers In general, it maps: * Traits to a struct with a void* and a list of function pointers, emulating what the compiler will do for a dyn trait anyway, * Structs as a struct with a single opaque pointer to the underlying type and a flag to indicate ownership. While this is a bit less effecient than just a direct pointer, it neatly lets us expose in the public interface the concept of ownership by setting a flag in the generated struct. * Unit enums as enums with each type copied over and conversion functions, * Non-unit enums have each field converted back and forth with a type flag and a union across all the C-mapped fields. --- diff --git a/c-bindings-gen/Cargo.toml b/c-bindings-gen/Cargo.toml new file mode 100644 index 00000000..6f4716e8 --- /dev/null +++ b/c-bindings-gen/Cargo.toml @@ -0,0 +1,12 @@ +[package] +name = "c-bindings-gen" +version = "0.0.1" +authors = ["Matt Corallo"] +edition = "2018" + +[dependencies] +syn = { version = "1", features = ["full", "extra-traits"] } +proc-macro2 = "1" + +# We're not in the workspace as we're just a binary code generator: +[workspace] diff --git a/c-bindings-gen/src/blocks.rs b/c-bindings-gen/src/blocks.rs new file mode 100644 index 00000000..9e255a15 --- /dev/null +++ b/c-bindings-gen/src/blocks.rs @@ -0,0 +1,373 @@ +//! Printing logic for basic blocks of Rust-mapped code - parts of functions and declarations but +//! not the full mapping logic. + +use std::collections::HashMap; +use std::fs::File; +use std::io::Write; +use proc_macro2::{TokenTree, Span}; + +use crate::types::*; + +/// Writes out a C++ wrapper class for the given type, which contains various utilities to access +/// the underlying C-mapped type safely avoiding some common memory management issues by handling +/// resource-freeing and prevending accidental raw copies. +pub fn write_cpp_wrapper(cpp_header_file: &mut File, ty: &str, has_destructor: bool) { + writeln!(cpp_header_file, "class {} {{", ty).unwrap(); + writeln!(cpp_header_file, "private:").unwrap(); + writeln!(cpp_header_file, "\tLDK{} self;", ty).unwrap(); + writeln!(cpp_header_file, "public:").unwrap(); + writeln!(cpp_header_file, "\t{}(const {}&) = delete;", ty, ty).unwrap(); + if has_destructor { + writeln!(cpp_header_file, "\t~{}() {{ {}_free(self); }}", ty, ty).unwrap(); + } + writeln!(cpp_header_file, "\t{}({}&& o) : self(o.self) {{ memset(&o, 0, sizeof({})); }}", ty, ty, ty).unwrap(); + writeln!(cpp_header_file, "\t{}(LDK{}&& m_self) : self(m_self) {{ memset(&m_self, 0, sizeof(LDK{})); }}", ty, ty, ty).unwrap(); + writeln!(cpp_header_file, "\toperator LDK{}() {{ LDK{} res = self; memset(&self, 0, sizeof(LDK{})); return res; }}", ty, ty, ty).unwrap(); + writeln!(cpp_header_file, "\tLDK{}* operator &() {{ return &self; }}", ty).unwrap(); + writeln!(cpp_header_file, "\tLDK{}* operator ->() {{ return &self; }}", ty).unwrap(); + writeln!(cpp_header_file, "\tconst LDK{}* operator &() const {{ return &self; }}", ty).unwrap(); + writeln!(cpp_header_file, "\tconst LDK{}* operator ->() const {{ return &self; }}", ty).unwrap(); + writeln!(cpp_header_file, "}};").unwrap(); +} + +/// Prints the docs from a given attribute list unless its tagged no export +pub fn writeln_docs(w: &mut W, attrs: &[syn::Attribute], prefix: &str) { + for attr in attrs.iter() { + let tokens_clone = attr.tokens.clone(); + let mut token_iter = tokens_clone.into_iter(); + if let Some(token) = token_iter.next() { + match token { + TokenTree::Punct(c) if c.as_char() == '=' => { + // syn gets '=' from '///' or '//!' as it is syntax for #[doc = ""] + }, + TokenTree::Group(_) => continue, // eg #[derive()] + _ => unimplemented!(), + } + } else { continue; } + match attr.style { + syn::AttrStyle::Inner(_) => { + match token_iter.next().unwrap() { + TokenTree::Literal(lit) => { + // Drop the first and last chars from lit as they are always " + let doc = format!("{}", lit); + writeln!(w, "{}//!{}", prefix, &doc[1..doc.len() - 1]).unwrap(); + }, + _ => unimplemented!(), + } + }, + syn::AttrStyle::Outer => { + match token_iter.next().unwrap() { + TokenTree::Literal(lit) => { + // Drop the first and last chars from lit as they are always " + let doc = format!("{}", lit); + writeln!(w, "{}///{}", prefix, &doc[1..doc.len() - 1]).unwrap(); + }, + _ => unimplemented!(), + } + }, + } + } +} + +/// Print the parameters in a method declaration, starting after the open parenthesis, through and +/// including the closing parenthesis and return value, but not including the open bracket or any +/// trailing semicolons. +/// +/// Usable both for a function definition and declaration. +/// +/// this_param is used when returning Self or accepting a self parameter, and should be the +/// concrete, mapped type. +pub fn write_method_params(w: &mut W, sig: &syn::Signature, associated_types: &HashMap<&syn::Ident, &syn::Ident>, this_param: &str, types: &mut TypeResolver, generics: Option<&GenericTypes>, self_ptr: bool, fn_decl: bool) { + if sig.constness.is_some() || sig.asyncness.is_some() || sig.unsafety.is_some() || + sig.abi.is_some() || sig.variadic.is_some() { + unimplemented!(); + } + if sig.generics.lt_token.is_some() { + for generic in sig.generics.params.iter() { + match generic { + syn::GenericParam::Type(_)|syn::GenericParam::Lifetime(_) => { + // We ignore these, if they're not on skipped args, we'll blow up + // later, and lifetimes we just hope the C client enforces. + }, + _ => unimplemented!(), + } + } + } + + let mut first_arg = true; + let mut num_unused = 0; + for inp in sig.inputs.iter() { + match inp { + syn::FnArg::Receiver(recv) => { + if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); } + write!(w, "this_arg: {}{}", + match (self_ptr, recv.mutability.is_some()) { + (true, true) => "*mut ", + (true, false) => "*const ", + (false, true) => "&mut ", + (false, false) => "&", + }, this_param).unwrap(); + assert!(first_arg); + first_arg = false; + }, + syn::FnArg::Typed(arg) => { + if types.skip_arg(&*arg.ty, generics) { continue; } + if !arg.attrs.is_empty() { unimplemented!(); } + let mut is_ref = if let syn::Type::Reference(_) = *arg.ty { true } else { false }; + if let syn::Type::Reference(syn::TypeReference { ref elem, .. }) = *arg.ty { + if let syn::Type::Slice(_) = &**elem { + // Slices are mapped to non-ref Vec types, so we want them to be mut + // letting us drain(..) the underlying Vec. + is_ref = false; + } + } + match &*arg.pat { + syn::Pat::Ident(ident) => { + if !ident.attrs.is_empty() || ident.subpat.is_some() { + unimplemented!(); + } + write!(w, "{}{}{}: ", if first_arg { "" } else { ", " }, if is_ref || !fn_decl { "" } else { "mut " }, ident.ident).unwrap(); + first_arg = false; + }, + syn::Pat::Wild(wild) => { + if !wild.attrs.is_empty() { unimplemented!(); } + write!(w, "{}unused_{}: ", if first_arg { "" } else { ", " }, num_unused).unwrap(); + num_unused += 1; + }, + _ => unimplemented!(), + } + types.write_c_type(w, &*arg.ty, generics, false); + } + } + } + write!(w, ")").unwrap(); + match &sig.output { + syn::ReturnType::Type(_, rtype) => { + write!(w, " -> ").unwrap(); + if let Some(mut remaining_path) = first_seg_self(&*rtype) { + if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) { + // We're returning an associated type in a trait impl. Its probably a safe bet + // that its also a trait, so just return the trait type. + let real_type = associated_types.get(associated_seg).unwrap(); + types.write_c_type(w, &syn::Type::Path(syn::TypePath { qself: None, + path: syn::PathSegment { + ident: (*real_type).clone(), + arguments: syn::PathArguments::None + }.into() + }), generics, true); + } else { + write!(w, "{}", this_param).unwrap(); + } + } else { + if let syn::Type::Reference(r) = &**rtype { + // We can't return a reference, cause we allocate things on the stack. + types.write_c_type(w, &*r.elem, generics, true); + } else { + types.write_c_type(w, &*rtype, generics, true); + } + } + }, + _ => {}, + } +} + +/// Print the main part of a method declaration body, starting with a newline after the function +/// open bracket and converting each function parameter to or from C-mapped types. Ends with "let +/// mut ret = " assuming the next print will be the unmapped Rust function to call followed by the +/// parameters we mapped to/from C here. +pub fn write_method_var_decl_body(w: &mut W, sig: &syn::Signature, extra_indent: &str, types: &TypeResolver, generics: Option<&GenericTypes>, to_c: bool) { + let mut num_unused = 0; + for inp in sig.inputs.iter() { + match inp { + syn::FnArg::Receiver(_) => {}, + syn::FnArg::Typed(arg) => { + if types.skip_arg(&*arg.ty, generics) { continue; } + if !arg.attrs.is_empty() { unimplemented!(); } + macro_rules! write_new_var { + ($ident: expr, $ty: expr) => { + if to_c { + if types.write_to_c_conversion_new_var(w, &$ident, &$ty, generics, false) { + write!(w, "\n\t{}", extra_indent).unwrap(); + } + } else { + if types.write_from_c_conversion_new_var(w, &$ident, &$ty, generics) { + write!(w, "\n\t{}", extra_indent).unwrap(); + } + } + } + } + match &*arg.pat { + syn::Pat::Ident(ident) => { + if !ident.attrs.is_empty() || ident.subpat.is_some() { + unimplemented!(); + } + write_new_var!(ident.ident, *arg.ty); + }, + syn::Pat::Wild(w) => { + if !w.attrs.is_empty() { unimplemented!(); } + write_new_var!(syn::Ident::new(&format!("unused_{}", num_unused), Span::call_site()), *arg.ty); + num_unused += 1; + }, + _ => unimplemented!(), + } + } + } + } + match &sig.output { + syn::ReturnType::Type(_, _) => { + write!(w, "let mut ret = ").unwrap(); + }, + _ => {}, + } +} + +/// Prints the parameters in a method call, starting after the open parenthesis and ending with a +/// final return statement returning the method's result. Should be followed by a single closing +/// bracket. +/// +/// The return value is expected to be bound to a variable named `ret` which is available after a +/// method-call-ending semicolon. +pub fn write_method_call_params(w: &mut W, sig: &syn::Signature, associated_types: &HashMap<&syn::Ident, &syn::Ident>, extra_indent: &str, types: &TypeResolver, generics: Option<&GenericTypes>, this_type: &str, to_c: bool) { + let mut first_arg = true; + let mut num_unused = 0; + for inp in sig.inputs.iter() { + match inp { + syn::FnArg::Receiver(recv) => { + if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); } + if to_c { + write!(w, "self.this_arg").unwrap(); + first_arg = false; + } + }, + syn::FnArg::Typed(arg) => { + if types.skip_arg(&*arg.ty, generics) { + if !to_c { + if !first_arg { + write!(w, ", ").unwrap(); + } + first_arg = false; + types.no_arg_to_rust(w, &*arg.ty, generics); + } + continue; + } + if !arg.attrs.is_empty() { unimplemented!(); } + macro_rules! write_ident { + ($ident: expr) => { + if !first_arg { + write!(w, ", ").unwrap(); + } + first_arg = false; + if to_c { + types.write_to_c_conversion_inline_prefix(w, &*arg.ty, generics, false); + write!(w, "{}", $ident).unwrap(); + types.write_to_c_conversion_inline_suffix(w, &*arg.ty, generics, false); + } else { + types.write_from_c_conversion_prefix(w, &*arg.ty, generics); + write!(w, "{}", $ident).unwrap(); + types.write_from_c_conversion_suffix(w, &*arg.ty, generics); + } + } + } + match &*arg.pat { + syn::Pat::Ident(ident) => { + if !ident.attrs.is_empty() || ident.subpat.is_some() { + unimplemented!(); + } + write_ident!(ident.ident); + }, + syn::Pat::Wild(w) => { + if !w.attrs.is_empty() { unimplemented!(); } + write_ident!(format!("unused_{}", num_unused)); + num_unused += 1; + }, + _ => unimplemented!(), + } + } + } + } + write!(w, ")").unwrap(); + match &sig.output { + syn::ReturnType::Type(_, rtype) => { + write!(w, ";\n\t{}", extra_indent).unwrap(); + + if to_c && first_seg_self(&*rtype).is_some() { + // Assume rather blindly that we're returning an associated trait from a C fn call to a Rust trait object. + write!(w, "ret").unwrap(); + } else if !to_c && first_seg_self(&*rtype).is_some() { + if let Some(mut remaining_path) = first_seg_self(&*rtype) { + if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) { + let real_type = associated_types.get(associated_seg).unwrap(); + if let Some(t) = types.crate_types.traits.get(&types.maybe_resolve_ident(&real_type).unwrap()) { + // We're returning an associated trait from a Rust fn call to a C trait + // object. + writeln!(w, "let mut rust_obj = {} {{ inner: Box::into_raw(Box::new(ret)), is_owned: true }};", this_type).unwrap(); + writeln!(w, "\t{}let mut ret = {}_as_{}(&rust_obj);", extra_indent, this_type, t.ident).unwrap(); + writeln!(w, "\t{}// We want to free rust_obj when ret gets drop()'d, not rust_obj, so wipe rust_obj's pointer and set ret's free() fn", extra_indent).unwrap(); + writeln!(w, "\t{}rust_obj.inner = std::ptr::null_mut();", extra_indent).unwrap(); + writeln!(w, "\t{}ret.free = Some({}_free_void);", extra_indent, this_type).unwrap(); + writeln!(w, "\t{}ret", extra_indent).unwrap(); + return; + } + } + } + write!(w, "{} {{ inner: Box::into_raw(Box::new(ret)), is_owned: true }}", this_type).unwrap(); + } else if to_c { + let new_var = types.write_from_c_conversion_new_var(w, &syn::Ident::new("ret", Span::call_site()), rtype, generics); + if new_var { + write!(w, "\n\t{}", extra_indent).unwrap(); + } + types.write_from_c_conversion_prefix(w, &*rtype, generics); + write!(w, "ret").unwrap(); + types.write_from_c_conversion_suffix(w, &*rtype, generics); + } else { + let ret_returned = if let syn::Type::Reference(_) = &**rtype { true } else { false }; + let new_var = types.write_to_c_conversion_new_var(w, &syn::Ident::new("ret", Span::call_site()), &rtype, generics, true); + if new_var { + write!(w, "\n\t{}", extra_indent).unwrap(); + } + types.write_to_c_conversion_inline_prefix(w, &rtype, generics, true); + write!(w, "{}ret", if ret_returned && !new_var { "*" } else { "" }).unwrap(); + types.write_to_c_conversion_inline_suffix(w, &rtype, generics, true); + } + } + _ => {}, + } +} + +/// Prints concrete generic parameters for a struct/trait/function, including the less-than and +/// greater-than symbols, if any generic parameters are defined. +pub fn maybe_write_generics(w: &mut W, generics: &syn::Generics, types: &TypeResolver, concrete_lifetimes: bool) { + let mut gen_types = GenericTypes::new(); + assert!(gen_types.learn_generics(generics, types)); + if !generics.params.is_empty() { + write!(w, "<").unwrap(); + for (idx, generic) in generics.params.iter().enumerate() { + match generic { + syn::GenericParam::Type(type_param) => { + let mut printed_param = false; + for bound in type_param.bounds.iter() { + if let syn::TypeParamBound::Trait(trait_bound) = bound { + assert_simple_bound(&trait_bound); + write!(w, "{}{}", if idx != 0 { ", " } else { "" }, gen_types.maybe_resolve_ident(&type_param.ident).unwrap()).unwrap(); + if printed_param { + unimplemented!("Can't print generic params that have multiple non-lifetime bounds"); + } + printed_param = true; + } + } + }, + syn::GenericParam::Lifetime(lt) => { + if concrete_lifetimes { + write!(w, "'static").unwrap(); + } else { + write!(w, "{}'{}", if idx != 0 { ", " } else { "" }, lt.lifetime.ident).unwrap(); + } + }, + _ => unimplemented!(), + } + } + write!(w, ">").unwrap(); + } +} + + diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs new file mode 100644 index 00000000..52ee3b05 --- /dev/null +++ b/c-bindings-gen/src/main.rs @@ -0,0 +1,1283 @@ +//! Converts a rust crate into a rust crate containing a number of C-exported wrapper functions and +//! classes (which is exportable using cbindgen). +//! In general, supports convering: +//! * structs as a pointer to the underlying type (either owned or not owned), +//! * traits as a void-ptr plus a jump table, +//! * enums as an equivalent enum with all the inner fields mapped to the mapped types, +//! * certain containers (tuples, slices, Vecs, Options, and Results currently) to a concrete +//! version of a defined container template. +//! +//! It also generates relevant memory-management functions and free-standing functions with +//! parameters mapped. + +use std::collections::HashMap; +use std::env; +use std::fs::File; +use std::io::{Read, Write}; +use std::path::Path; +use std::process; + +use proc_macro2::{TokenTree, TokenStream, Span}; + +mod types; +mod blocks; +use types::*; +use blocks::*; + +// ************************************* +// *** Manually-expanded conversions *** +// ************************************* + +/// Because we don't expand macros, any code that we need to generated based on their contents has +/// to be completely manual. In this case its all just serialization, so its not too hard. +fn convert_macro(w: &mut W, macro_path: &syn::Path, stream: &TokenStream, types: &TypeResolver) { + assert_eq!(macro_path.segments.len(), 1); + match &format!("{}", macro_path.segments.iter().next().unwrap().ident) as &str { + "impl_writeable" | "impl_writeable_len_match" => { + let struct_for = if let TokenTree::Ident(i) = stream.clone().into_iter().next().unwrap() { i } else { unimplemented!(); }; + if let Some(s) = types.maybe_resolve_ident(&struct_for) { + if !types.crate_types.opaques.get(&s).is_some() { return; } + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_write(obj: *const {}) -> crate::c_types::derived::CVec_u8Z {{", struct_for, struct_for).unwrap(); + writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap(); + writeln!(w, "}}").unwrap(); + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice) -> {} {{", struct_for, struct_for).unwrap(); + writeln!(w, "\tif let Ok(res) = crate::c_types::deserialize_obj(ser) {{").unwrap(); + writeln!(w, "\t\t{} {{ inner: Box::into_raw(Box::new(res)), is_owned: true }}", struct_for).unwrap(); + writeln!(w, "\t}} else {{").unwrap(); + writeln!(w, "\t\t{} {{ inner: std::ptr::null_mut(), is_owned: true }}", struct_for).unwrap(); + writeln!(w, "\t}}\n}}").unwrap(); + } + }, + _ => {}, + } +} + +/// Convert "impl trait_path for for_obj { .. }" for manually-mapped types (ie (de)serialization) +fn maybe_convert_trait_impl(w: &mut W, trait_path: &syn::Path, for_obj: &syn::Ident, types: &TypeResolver) { + if let Some(t) = types.maybe_resolve_path(&trait_path) { + let s = types.maybe_resolve_ident(for_obj).unwrap(); + if !types.crate_types.opaques.get(&s).is_some() { return; } + match &t as &str { + "util::ser::Writeable" => { + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_write(obj: *const {}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, for_obj).unwrap(); + writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap(); + writeln!(w, "}}").unwrap(); + }, + "util::ser::Readable" => { + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice) -> {} {{", for_obj, for_obj).unwrap(); + writeln!(w, "\tif let Ok(res) = crate::c_types::deserialize_obj(ser) {{").unwrap(); + writeln!(w, "\t\t{} {{ inner: Box::into_raw(Box::new(res)), is_owned: true }}", for_obj).unwrap(); + writeln!(w, "\t}} else {{").unwrap(); + writeln!(w, "\t\t{} {{ inner: std::ptr::null_mut(), is_owned: true }}", for_obj).unwrap(); + writeln!(w, "\t}}\n}}").unwrap(); + }, + _ => {}, + } + } +} + +// ******************************* +// *** Per-Type Printing Logic *** +// ******************************* + +macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $pat: pat => $e: expr),*) ) => { { + if $t.colon_token.is_some() { + for st in $t.supertraits.iter() { + match st { + syn::TypeParamBound::Trait(supertrait) => { + if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() { + unimplemented!(); + } + if let Some(ident) = supertrait.path.get_ident() { + match (&format!("{}", ident) as &str, &ident) { + $( $pat => $e, )* + } + } else { + let path = $types.resolve_path(&supertrait.path); + match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) { + $( $pat => $e, )* + } + } + }, + syn::TypeParamBound::Lifetime(_) => unimplemented!(), + } + } + } +} } } + +/// Gets a HashMap from name idents to the bounding trait for associated types. +/// eg if a native trait has a "type T = TraitA", this will return a HashMap containing a mapping +/// from "T" to "TraitA". +fn learn_associated_types<'a>(t: &'a syn::ItemTrait) -> HashMap<&'a syn::Ident, &'a syn::Ident> { + let mut associated_types = HashMap::new(); + for item in t.items.iter() { + match item { + &syn::TraitItem::Type(ref t) => { + if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); } + let mut bounds_iter = t.bounds.iter(); + match bounds_iter.next().unwrap() { + syn::TypeParamBound::Trait(tr) => { + assert_simple_bound(&tr); + associated_types.insert(&t.ident, assert_single_path_seg(&tr.path)); + }, + _ => unimplemented!(), + } + if bounds_iter.next().is_some() { unimplemented!(); } + }, + _ => {}, + } + } + associated_types +} + +/// Prints a C-mapped trait object containing a void pointer and a jump table for each function in +/// the original trait. +/// Implements the native Rust trait and relevant parent traits for the new C-mapped trait. +/// +/// Finally, implements Deref for MappedTrait which allows its use in types which need +/// a concrete Deref to the Rust trait. +fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, types: &mut TypeResolver<'b, 'a>, extra_headers: &mut File, cpp_headers: &mut File) { + let trait_name = format!("{}", t.ident); + match export_status(&t.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => return, + } + writeln_docs(w, &t.attrs, ""); + + writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap(); + writeln!(w, "\tpub this_arg: *mut c_void,").unwrap(); + let associated_types = learn_associated_types(t); + let mut generated_fields = Vec::new(); // Every field's name except this_arg, used in Clone generation + for item in t.items.iter() { + match item { + &syn::TraitItem::Method(ref m) => { + match export_status(&m.attrs) { + ExportStatus::NoExport => { + // NoExport in this context means we'll hit an unimplemented!() at runtime, + // so add a comment noting that this needs to change in the output. + writeln!(w, "\t//XXX: Need to export {}", m.sig.ident).unwrap(); + continue; + }, + ExportStatus::Export => {}, + ExportStatus::TestOnly => continue, + } + if m.default.is_some() { unimplemented!(); } + + writeln_docs(w, &m.attrs, "\t"); + + if let syn::ReturnType::Type(_, rtype) = &m.sig.output { + if let syn::Type::Reference(r) = &**rtype { + // We have to do quite a dance for trait functions which return references + // - they ultimately require us to have a native Rust object stored inside + // our concrete trait to return a reference to. However, users may wish to + // update the value to be returned each time the function is called (or, to + // make C copies of Rust impls equivalent, we have to be able to). + // + // Thus, we store a copy of the C-mapped type (which is just a pointer to + // the Rust type and a flag to indicate whether deallocation needs to + // happen) as well as provide an Option<>al function pointer which is + // called when the trait method is called which allows updating on the fly. + write!(w, "\tpub {}: ", m.sig.ident).unwrap(); + generated_fields.push(format!("{}", m.sig.ident)); + types.write_c_type(w, &*r.elem, None, false); + writeln!(w, ",").unwrap(); + writeln!(w, "\t/// Fill in the {} field as a reference to it will be given to Rust after this returns", m.sig.ident).unwrap(); + writeln!(w, "\t/// Note that this takes a pointer to this object, not the this_ptr like other methods do").unwrap(); + writeln!(w, "\t/// This function pointer may be NULL if {} is filled in when this object is created and never needs updating.", m.sig.ident).unwrap(); + writeln!(w, "\tpub set_{}: Option,", m.sig.ident, trait_name).unwrap(); + generated_fields.push(format!("set_{}", m.sig.ident)); + // Note that cbindgen will now generate + // typedef struct Thing {..., set_thing: (const Thing*), ...} Thing; + // which does not compile since Thing is not defined before it is used. + writeln!(extra_headers, "struct LDK{};", trait_name).unwrap(); + writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap(); + continue; + } + // Sadly, this currently doesn't do what we want, but it should be easy to get + // cbindgen to support it. See https://github.com/eqrion/cbindgen/issues/531 + writeln!(w, "\t#[must_use]").unwrap(); + } + + write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap(); + generated_fields.push(format!("{}", m.sig.ident)); + write_method_params(w, &m.sig, &associated_types, "c_void", types, None, true, false); + writeln!(w, ",").unwrap(); + }, + &syn::TraitItem::Type(_) => {}, + _ => unimplemented!(), + } + } + // Add functions which may be required for supertrait implementations. + walk_supertraits!(t, types, ( + ("Clone", _) => { + writeln!(w, "\tpub clone: Option *mut c_void>,").unwrap(); + generated_fields.push("clone".to_owned()); + }, + ("std::cmp::Eq", _) => { + writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: *const c_void) -> bool,").unwrap(); + generated_fields.push("eq".to_owned()); + }, + ("std::hash::Hash", _) => { + writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap(); + generated_fields.push("hash".to_owned()); + }, + ("Send", _) => {}, ("Sync", _) => {}, + (s, i) => { + // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member. + if types.crate_types.traits.get(s).is_none() { unimplemented!(); } + writeln!(w, "\tpub {}: crate::{},", i, s).unwrap(); + generated_fields.push(format!("{}", i)); + } + ) ); + writeln!(w, "\tpub free: Option,").unwrap(); + generated_fields.push("free".to_owned()); + writeln!(w, "}}").unwrap(); + // Implement supertraits for the C-mapped struct. + walk_supertraits!(t, types, ( + ("Send", _) => writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(), + ("Sync", _) => writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(), + ("std::cmp::Eq", _) => { + writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap(); + writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap(); + writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o.this_arg) }}\n}}").unwrap(); + }, + ("std::hash::Hash", _) => { + writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap(); + writeln!(w, "\tfn hash(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap(); + }, + ("Clone", _) => { + writeln!(w, "impl Clone for {} {{", trait_name).unwrap(); + writeln!(w, "\tfn clone(&self) -> Self {{").unwrap(); + writeln!(w, "\t\tSelf {{").unwrap(); + writeln!(w, "\t\tthis_arg: if let Some(f) = self.clone {{ (f)(self.this_arg) }} else {{ self.this_arg }},").unwrap(); + for field in generated_fields.iter() { + writeln!(w, "\t\t\t{}: self.{}.clone(),", field, field).unwrap(); + } + writeln!(w, "\t\t}}\n\t}}\n}}").unwrap(); + }, + (s, i) => { + if s != "util::events::MessageSendEventsProvider" { unimplemented!(); } + // XXX: We straight-up cheat here - instead of bothering to get the trait object we + // just print what we need since this is only used in one place. + writeln!(w, "impl lightning::{} for {} {{", s, trait_name).unwrap(); + writeln!(w, "\tfn get_and_clear_pending_msg_events(&self) -> Vec {{").unwrap(); + writeln!(w, "\t\t::get_and_clear_pending_msg_events(&self.{})", s, s, i).unwrap(); + writeln!(w, "\t}}\n}}").unwrap(); + } + ) ); + + // Finally, implement the original Rust trait for the newly created mapped trait. + writeln!(w, "\nuse {}::{}::{} as rust{};", types.orig_crate, types.module_path, t.ident, trait_name).unwrap(); + write!(w, "impl rust{}", t.ident).unwrap(); + maybe_write_generics(w, &t.generics, types, false); + writeln!(w, " for {} {{", trait_name).unwrap(); + for item in t.items.iter() { + match item { + syn::TraitItem::Method(m) => { + if let ExportStatus::TestOnly = export_status(&m.attrs) { continue; } + if m.default.is_some() { unimplemented!(); } + if m.sig.constness.is_some() || m.sig.asyncness.is_some() || m.sig.unsafety.is_some() || + m.sig.abi.is_some() || m.sig.variadic.is_some() { + unimplemented!(); + } + write!(w, "\tfn {}", m.sig.ident).unwrap(); + types.write_rust_generic_param(w, m.sig.generics.params.iter()); + write!(w, "(").unwrap(); + for inp in m.sig.inputs.iter() { + match inp { + syn::FnArg::Receiver(recv) => { + if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); } + write!(w, "&").unwrap(); + if let Some(lft) = &recv.reference.as_ref().unwrap().1 { + write!(w, "'{} ", lft.ident).unwrap(); + } + if recv.mutability.is_some() { + write!(w, "mut self").unwrap(); + } else { + write!(w, "self").unwrap(); + } + }, + syn::FnArg::Typed(arg) => { + if !arg.attrs.is_empty() { unimplemented!(); } + match &*arg.pat { + syn::Pat::Ident(ident) => { + if !ident.attrs.is_empty() || ident.by_ref.is_some() || + ident.mutability.is_some() || ident.subpat.is_some() { + unimplemented!(); + } + write!(w, ", {}{}: ", if types.skip_arg(&*arg.ty, None) { "_" } else { "" }, ident.ident).unwrap(); + } + _ => unimplemented!(), + } + types.write_rust_type(w, &*arg.ty); + } + } + } + write!(w, ")").unwrap(); + match &m.sig.output { + syn::ReturnType::Type(_, rtype) => { + write!(w, " -> ").unwrap(); + types.write_rust_type(w, &*rtype) + }, + _ => {}, + } + write!(w, " {{\n\t\t").unwrap(); + match export_status(&m.attrs) { + ExportStatus::NoExport => { + writeln!(w, "unimplemented!();\n\t}}").unwrap(); + continue; + }, + _ => {}, + } + if let syn::ReturnType::Type(_, rtype) = &m.sig.output { + if let syn::Type::Reference(r) = &**rtype { + assert_eq!(m.sig.inputs.len(), 1); // Must only take self! + writeln!(w, "if let Some(f) = self.set_{} {{", m.sig.ident).unwrap(); + writeln!(w, "\t\t\t(f)(self);").unwrap(); + write!(w, "\t\t}}\n\t\t").unwrap(); + types.write_from_c_conversion_to_ref_prefix(w, &*r.elem, None); + write!(w, "self.{}", m.sig.ident).unwrap(); + types.write_from_c_conversion_to_ref_suffix(w, &*r.elem, None); + writeln!(w, "\n\t}}").unwrap(); + continue; + } + } + write_method_var_decl_body(w, &m.sig, "\t", types, None, true); + write!(w, "(self.{})(", m.sig.ident).unwrap(); + write_method_call_params(w, &m.sig, &associated_types, "\t", types, None, "", true); + + writeln!(w, "\n\t}}").unwrap(); + }, + &syn::TraitItem::Type(ref t) => { + if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); } + let mut bounds_iter = t.bounds.iter(); + match bounds_iter.next().unwrap() { + syn::TypeParamBound::Trait(tr) => { + writeln!(w, "\ttype {} = crate::{};", t.ident, types.resolve_path(&tr.path)).unwrap(); + }, + _ => unimplemented!(), + } + if bounds_iter.next().is_some() { unimplemented!(); } + }, + _ => unimplemented!(), + } + } + writeln!(w, "}}\n").unwrap(); + writeln!(w, "// We're essentially a pointer already, or at least a set of pointers, so allow us to be used").unwrap(); + writeln!(w, "// directly as a Deref trait in higher-level structs:").unwrap(); + writeln!(w, "impl std::ops::Deref for {} {{\n\ttype Target = Self;", trait_name).unwrap(); + writeln!(w, "\tfn deref(&self) -> &Self {{\n\t\tself\n\t}}\n}}").unwrap(); + + writeln!(w, "/// Calls the free function if one is set").unwrap(); + writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", trait_name, trait_name).unwrap(); + writeln!(w, "impl Drop for {} {{", trait_name).unwrap(); + writeln!(w, "\tfn drop(&mut self) {{").unwrap(); + writeln!(w, "\t\tif let Some(f) = self.free {{").unwrap(); + writeln!(w, "\t\t\tf(self.this_arg);").unwrap(); + writeln!(w, "\t\t}}\n\t}}\n}}").unwrap(); + + write_cpp_wrapper(cpp_headers, &trait_name, true); + types.trait_declared(&t.ident, t); +} + +/// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type +/// and a flag to indicate whether Drop'ing the mapped struct drops the underlying Rust type. +/// +/// Also writes out a _free function and a C++ wrapper which handles calling _free. +fn writeln_opaque(w: &mut W, ident: &syn::Ident, struct_name: &str, generics: &syn::Generics, attrs: &[syn::Attribute], types: &TypeResolver, extra_headers: &mut File, cpp_headers: &mut File) { + // If we directly read the original type by its original name, cbindgen hits + // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary + // name and then reference it by that name, which works around the issue. + write!(w, "\nuse {}::{}::{} as native{}Import;\ntype native{} = native{}Import", types.orig_crate, types.module_path, ident, ident, ident, ident).unwrap(); + maybe_write_generics(w, &generics, &types, true); + writeln!(w, ";\n").unwrap(); + writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap(); + writeln_docs(w, &attrs, ""); + writeln!(w, "#[must_use]\n#[repr(C)]\npub struct {} {{\n\t/// Nearly everyhwere, inner must be non-null, however in places where", struct_name).unwrap(); + writeln!(w, "\t/// the Rust equivalent takes an Option, it may be set to null to indicate None.").unwrap(); + writeln!(w, "\tpub inner: *mut native{},\n\tpub is_owned: bool,\n}}\n", ident).unwrap(); + writeln!(w, "impl Drop for {} {{\n\tfn drop(&mut self) {{", struct_name).unwrap(); + writeln!(w, "\t\tif self.is_owned && !self.inner.is_null() {{").unwrap(); + writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(self.inner) }};\n\t\t}}\n\t}}\n}}").unwrap(); + writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", struct_name, struct_name).unwrap(); + writeln!(w, "#[allow(unused)]").unwrap(); + writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap(); + writeln!(w, "extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap(); + writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap(); + writeln!(w, "#[allow(unused)]").unwrap(); + writeln!(w, "/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap(); + writeln!(w, "impl {} {{", struct_name).unwrap(); + writeln!(w, "\tpub(crate) fn take_ptr(mut self) -> *mut native{} {{", struct_name).unwrap(); + writeln!(w, "\t\tassert!(self.is_owned);").unwrap(); + writeln!(w, "\t\tlet ret = self.inner;").unwrap(); + writeln!(w, "\t\tself.inner = std::ptr::null_mut();").unwrap(); + writeln!(w, "\t\tret").unwrap(); + writeln!(w, "\t}}\n}}").unwrap(); + + 'attr_loop: for attr in attrs.iter() { + let tokens_clone = attr.tokens.clone(); + let mut token_iter = tokens_clone.into_iter(); + if let Some(token) = token_iter.next() { + match token { + TokenTree::Group(g) => { + if format!("{}", single_ident_generic_path_to_ident(&attr.path).unwrap()) == "derive" { + for id in g.stream().into_iter() { + if let TokenTree::Ident(i) = id { + if i == "Clone" { + writeln!(w, "impl Clone for {} {{", struct_name).unwrap(); + writeln!(w, "\tfn clone(&self) -> Self {{").unwrap(); + writeln!(w, "\t\tSelf {{").unwrap(); + writeln!(w, "\t\t\tinner: Box::into_raw(Box::new(unsafe {{ &*self.inner }}.clone())),").unwrap(); + writeln!(w, "\t\t\tis_owned: true,").unwrap(); + writeln!(w, "\t\t}}\n\t}}\n}}").unwrap(); + writeln!(w, "#[allow(unused)]").unwrap(); + writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap(); + writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", struct_name).unwrap(); + writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", struct_name).unwrap(); + writeln!(w, "}}").unwrap(); + break 'attr_loop; + } + } + } + } + }, + _ => {}, + } + } + } + + write_cpp_wrapper(cpp_headers, &format!("{}", ident), true); +} + +/// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate +/// the struct itself, and then writing getters and setters for public, understood-type fields and +/// a constructor if every field is public. +fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct, types: &mut TypeResolver<'b, 'a>, extra_headers: &mut File, cpp_headers: &mut File) { + let struct_name = &format!("{}", s.ident); + let export = export_status(&s.attrs); + match export { + ExportStatus::Export => {}, + ExportStatus::TestOnly => return, + ExportStatus::NoExport => { + types.struct_ignored(&s.ident); + return; + } + } + + writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers); + + eprintln!("exporting fields for {}", struct_name); + if let syn::Fields::Named(fields) = &s.fields { + let mut gen_types = GenericTypes::new(); + assert!(gen_types.learn_generics(&s.generics, types)); + + let mut all_fields_settable = true; + for field in fields.named.iter() { + if let syn::Visibility::Public(_) = field.vis { + let export = export_status(&field.attrs); + match export { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => { + all_fields_settable = false; + continue + }, + } + + if let Some(ident) = &field.ident { + let ref_type = syn::Type::Reference(syn::TypeReference { + and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None, + elem: Box::new(field.ty.clone()) }); + if types.understood_c_type(&ref_type, Some(&gen_types)) { + writeln_docs(w, &field.attrs, ""); + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, ident, struct_name).unwrap(); + types.write_c_type(w, &ref_type, Some(&gen_types), true); + write!(w, " {{\n\tlet mut inner_val = &mut unsafe {{ &mut *this_ptr.inner }}.{};\n\t", ident).unwrap(); + let local_var = types.write_to_c_conversion_new_var(w, &syn::Ident::new("inner_val", Span::call_site()), &ref_type, Some(&gen_types), true); + if local_var { write!(w, "\n\t").unwrap(); } + types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true); + if local_var { + write!(w, "inner_val").unwrap(); + } else { + write!(w, "(*inner_val)").unwrap(); + } + types.write_to_c_conversion_inline_suffix(w, &ref_type, Some(&gen_types), true); + writeln!(w, "\n}}").unwrap(); + } + + if types.understood_c_type(&field.ty, Some(&gen_types)) { + writeln_docs(w, &field.attrs, ""); + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, ident, struct_name).unwrap(); + types.write_c_type(w, &field.ty, Some(&gen_types), false); + write!(w, ") {{\n\t").unwrap(); + let local_var = types.write_from_c_conversion_new_var(w, &syn::Ident::new("val", Span::call_site()), &field.ty, Some(&gen_types)); + if local_var { write!(w, "\n\t").unwrap(); } + write!(w, "unsafe {{ &mut *this_ptr.inner }}.{} = ", ident).unwrap(); + types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types)); + write!(w, "val").unwrap(); + types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types)); + writeln!(w, ";\n}}").unwrap(); + } else { all_fields_settable = false; } + } else { all_fields_settable = false; } + } else { all_fields_settable = false; } + } + + if all_fields_settable { + // Build a constructor! + write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_new(", struct_name).unwrap(); + for (idx, field) in fields.named.iter().enumerate() { + if idx != 0 { write!(w, ", ").unwrap(); } + write!(w, "mut {}_arg: ", field.ident.as_ref().unwrap()).unwrap(); + types.write_c_type(w, &field.ty, Some(&gen_types), false); + } + write!(w, ") -> {} {{\n\t", struct_name).unwrap(); + for field in fields.named.iter() { + let field_name = format!("{}_arg", field.ident.as_ref().unwrap()); + if types.write_from_c_conversion_new_var(w, &syn::Ident::new(&field_name, Span::call_site()), &field.ty, Some(&gen_types)) { + write!(w, "\n\t").unwrap(); + } + } + writeln!(w, "{} {{ inner: Box::into_raw(Box::new(native{} {{", struct_name, s.ident).unwrap(); + for field in fields.named.iter() { + write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap(); + types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types)); + write!(w, "{}_arg", field.ident.as_ref().unwrap()).unwrap(); + types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types)); + writeln!(w, ",").unwrap(); + } + writeln!(w, "\t}})), is_owned: true }}\n}}").unwrap(); + } + } + + types.struct_imported(&s.ident, struct_name.clone()); +} + +/// Prints a relevant conversion for impl * +/// +/// For simple impl Struct {}s, this just outputs the wrapper functions as Struct_fn_name() { .. }. +/// +/// For impl Trait for Struct{}s, this non-exported generates wrapper functions as +/// Trait_Struct_fn_name and a Struct_as_Trait(&struct) -> Trait function which returns a populated +/// Trait struct containing a pointer to the passed struct's inner field and the wrapper functions. +/// +/// 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::Path(ref p) = &*i.self_ty { + if p.qself.is_some() { unimplemented!(); } + if let Some(ident) = single_ident_generic_path_to_ident(&p.path) { + if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) { + 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", ident); + 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) { + let full_trait_path = types.resolve_path(&trait_path.1); + let trait_obj = *types.crate_types.traits.get(&full_trait_path).unwrap(); + // We learn the associated types maping from the original trait object. + // That's great, except that they are unresolved idents, so if we learn + // mappings from a trai defined in a different file, we may mis-resolve or + // fail to resolve the mapped types. + let trait_associated_types = learn_associated_types(trait_obj); + let mut impl_associated_types = HashMap::new(); + for item in i.items.iter() { + match item { + syn::ImplItem::Type(t) => { + if let syn::Type::Path(p) = &t.ty { + if let Some(id) = single_ident_generic_path_to_ident(&p.path) { + impl_associated_types.insert(&t.ident, id); + } + } + }, + _ => {}, + } + } + + let export = export_status(&trait_obj.attrs); + match export { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => return, + } + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: *const {}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap(); + writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap(); + writeln!(w, "\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap(); + writeln!(w, "\t\tfree: None,").unwrap(); + + macro_rules! write_meth { + ($m: expr, $trait: expr, $indent: expr) => { + let trait_method = $trait.items.iter().filter_map(|item| { + if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None } + }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap(); + match export_status(&trait_method.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport => { + write!(w, "{}\t\t//XXX: Need to export {}\n", $indent, $m.sig.ident).unwrap(); + continue; + }, + ExportStatus::TestOnly => continue, + } + + let mut printed = false; + if let syn::ReturnType::Type(_, rtype) = &$m.sig.output { + if let syn::Type::Reference(r) = &**rtype { + write!(w, "\n\t\t{}{}: ", $indent, $m.sig.ident).unwrap(); + types.write_empty_rust_val(w, &*r.elem); + writeln!(w, ",\n{}\t\tset_{}: Some({}_{}_set_{}),", $indent, $m.sig.ident, ident, trait_obj.ident, $m.sig.ident).unwrap(); + printed = true; + } + } + if !printed { + write!(w, "{}\t\t{}: {}_{}_{},\n", $indent, $m.sig.ident, ident, trait_obj.ident, $m.sig.ident).unwrap(); + } + } + } + for item in trait_obj.items.iter() { + match item { + syn::TraitItem::Method(m) => { + write_meth!(m, trait_obj, ""); + }, + _ => {}, + } + } + walk_supertraits!(trait_obj, types, ( + ("Clone", _) => { + writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap(); + }, + (s, t) => { + if s.starts_with("util::") { + let supertrait_obj = types.crate_types.traits.get(s).unwrap(); + writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap(); + writeln!(w, "\t\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap(); + writeln!(w, "\t\t\tfree: None,").unwrap(); + for item in supertrait_obj.items.iter() { + match item { + syn::TraitItem::Method(m) => { + write_meth!(m, supertrait_obj, "\t"); + }, + _ => {}, + } + } + write!(w, "\t\t}},\n").unwrap(); + } + } + ) ); + write!(w, "\t}}\n}}\nuse {}::{} as {}TraitImport;\n", types.orig_crate, full_trait_path, trait_obj.ident).unwrap(); + + macro_rules! impl_meth { + ($m: expr, $trait: expr, $indent: expr) => { + let trait_method = $trait.items.iter().filter_map(|item| { + if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None } + }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap(); + match export_status(&trait_method.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + + if let syn::ReturnType::Type(_, _) = &$m.sig.output { + writeln!(w, "#[must_use]").unwrap(); + } + write!(w, "extern \"C\" fn {}_{}_{}(", ident, trait_obj.ident, $m.sig.ident).unwrap(); + gen_types.push_ctx(); + assert!(gen_types.learn_generics(&$m.sig.generics, types)); + write_method_params(w, &$m.sig, &trait_associated_types, "c_void", types, Some(&gen_types), true, true); + write!(w, " {{\n\t").unwrap(); + write_method_var_decl_body(w, &$m.sig, "", types, Some(&gen_types), false); + let mut takes_self = false; + for inp in $m.sig.inputs.iter() { + if let syn::FnArg::Receiver(_) = inp { + takes_self = true; + } + } + if takes_self { + write!(w, "unsafe {{ &mut *(this_arg as *mut native{}) }}.{}(", ident, $m.sig.ident).unwrap(); + } else { + write!(w, "{}::{}::{}(", types.orig_crate, resolved_path, $m.sig.ident).unwrap(); + } + + let mut real_type = "".to_string(); + match &$m.sig.output { + syn::ReturnType::Type(_, rtype) => { + if let Some(mut remaining_path) = first_seg_self(&*rtype) { + if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) { + real_type = format!("{}", impl_associated_types.get(associated_seg).unwrap()); + } + } + }, + _ => {}, + } + write_method_call_params(w, &$m.sig, &trait_associated_types, "", types, Some(&gen_types), &real_type, false); + gen_types.pop_ctx(); + write!(w, "\n}}\n").unwrap(); + if let syn::ReturnType::Type(_, rtype) = &$m.sig.output { + if let syn::Type::Reference(r) = &**rtype { + assert_eq!($m.sig.inputs.len(), 1); // Must only take self + writeln!(w, "extern \"C\" fn {}_{}_set_{}(trait_self_arg: &{}) {{", ident, trait_obj.ident, $m.sig.ident, trait_obj.ident).unwrap(); + writeln!(w, "\t// This is a bit race-y in the general case, but for our specific use-cases today, we're safe").unwrap(); + writeln!(w, "\t// Specifically, we must ensure that the first time we're called it can never be in parallel").unwrap(); + write!(w, "\tif ").unwrap(); + types.write_empty_rust_val_check(w, &*r.elem, &format!("trait_self_arg.{}", $m.sig.ident)); + writeln!(w, " {{").unwrap(); + writeln!(w, "\t\tunsafe {{ &mut *(trait_self_arg as *const {} as *mut {}) }}.{} = {}_{}_{}(trait_self_arg.this_arg);", trait_obj.ident, trait_obj.ident, $m.sig.ident, ident, trait_obj.ident, $m.sig.ident).unwrap(); + writeln!(w, "\t}}").unwrap(); + writeln!(w, "}}").unwrap(); + } + } + } + } + + for item in i.items.iter() { + match item { + syn::ImplItem::Method(m) => { + impl_meth!(m, trait_obj, ""); + }, + syn::ImplItem::Type(_) => {}, + _ => unimplemented!(), + } + } + walk_supertraits!(trait_obj, types, ( + (s, t) => { + if s.starts_with("util::") { + writeln!(w, "use {}::{} as native{}Trait;", types.orig_crate, s, t).unwrap(); + let supertrait_obj = *types.crate_types.traits.get(s).unwrap(); + for item in supertrait_obj.items.iter() { + match item { + syn::TraitItem::Method(m) => { + impl_meth!(m, supertrait_obj, "\t"); + }, + _ => {}, + } + } + } + } + ) ); + write!(w, "\n").unwrap(); + } else if let Some(trait_ident) = trait_path.1.get_ident() { + //XXX: implement for other things like ToString + match &format!("{}", trait_ident) as &str { + "From" => {}, + "Default" => { + write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_default() -> {} {{\n", ident, ident).unwrap(); + write!(w, "\t{} {{ inner: Box::into_raw(Box::new(Default::default())), is_owned: true }}\n", ident).unwrap(); + write!(w, "}}\n").unwrap(); + }, + "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, &ident, 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, &ident, types); + } + } else { + let declared_type = (*types.get_declared_type(&ident).unwrap()).clone(); + for item in i.items.iter() { + match item { + syn::ImplItem::Method(m) => { + if let syn::Visibility::Public(_) = m.vis { + match export_status(&m.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + if m.defaultness.is_some() { unimplemented!(); } + writeln_docs(w, &m.attrs, ""); + if let syn::ReturnType::Type(_, _) = &m.sig.output { + writeln!(w, "#[must_use]").unwrap(); + } + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}(", ident, m.sig.ident).unwrap(); + let ret_type = match &declared_type { + DeclType::MirroredEnum => format!("{}", ident), + DeclType::StructImported => format!("{}", ident), + _ => unimplemented!(), + }; + gen_types.push_ctx(); + assert!(gen_types.learn_generics(&m.sig.generics, types)); + write_method_params(w, &m.sig, &HashMap::new(), &ret_type, types, Some(&gen_types), false, true); + write!(w, " {{\n\t").unwrap(); + write_method_var_decl_body(w, &m.sig, "", types, Some(&gen_types), false); + let mut takes_self = false; + let mut takes_mut_self = false; + for inp in m.sig.inputs.iter() { + if let syn::FnArg::Receiver(r) = inp { + takes_self = true; + if r.mutability.is_some() { takes_mut_self = true; } + } + } + if takes_mut_self { + write!(w, "unsafe {{ &mut (*(this_arg.inner as *mut native{})) }}.{}(", ident, m.sig.ident).unwrap(); + } else if takes_self { + write!(w, "unsafe {{ &*this_arg.inner }}.{}(", m.sig.ident).unwrap(); + } else { + write!(w, "{}::{}::{}(", types.orig_crate, resolved_path, m.sig.ident).unwrap(); + } + write_method_call_params(w, &m.sig, &HashMap::new(), "", types, Some(&gen_types), &ret_type, false); + gen_types.pop_ctx(); + writeln!(w, "\n}}\n").unwrap(); + } + }, + _ => {}, + } + } + } + } else { + eprintln!("Not implementing anything for {} due to no-resolve (probably the type isn't pub or its marked not exported)", ident); + } + } + } +} + +/// Returns true if the enum will be mapped as an opaue (ie struct with a pointer to the underlying +/// type), otherwise it is mapped into a transparent, C-compatible version of itself. +fn is_enum_opaque(e: &syn::ItemEnum) -> bool { + for var in e.variants.iter() { + if let syn::Fields::Unit = var.fields { + } else if let syn::Fields::Named(fields) = &var.fields { + for field in fields.named.iter() { + match export_status(&field.attrs) { + ExportStatus::Export|ExportStatus::TestOnly => {}, + ExportStatus::NoExport => return true, + } + } + } else { + return true; + } + } + false +} + +/// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum +/// is unitary), we generate an equivalent enum with all types replaced with their C mapped +/// versions followed by conversion functions which map between the Rust version and the C mapped +/// version. +fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, types: &mut TypeResolver<'b, 'a>, extra_headers: &mut File, cpp_headers: &mut File) { + match export_status(&e.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => return, + } + + if is_enum_opaque(e) { + eprintln!("Skipping enum {} as it contains non-unit fields", e.ident); + writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers); + types.enum_ignored(&e.ident); + return; + } + writeln_docs(w, &e.attrs, ""); + + if e.generics.lt_token.is_some() { + unimplemented!(); + } + types.mirrored_enum_declared(&e.ident); + + let mut needs_free = false; + + writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap(); + for var in e.variants.iter() { + assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum + writeln_docs(w, &var.attrs, "\t"); + write!(w, "\t{}", var.ident).unwrap(); + if let syn::Fields::Named(fields) = &var.fields { + needs_free = true; + writeln!(w, " {{").unwrap(); + for field in fields.named.iter() { + if export_status(&field.attrs) == ExportStatus::TestOnly { continue; } + write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap(); + types.write_c_type(w, &field.ty, None, false); + writeln!(w, ",").unwrap(); + } + write!(w, "\t}}").unwrap(); + } + if var.discriminant.is_some() { unimplemented!(); } + writeln!(w, ",").unwrap(); + } + writeln!(w, "}}\nuse {}::{}::{} as native{};\nimpl {} {{", types.orig_crate, types.module_path, e.ident, e.ident, e.ident).unwrap(); + + macro_rules! write_conv { + ($fn_sig: expr, $to_c: expr, $ref: expr) => { + writeln!(w, "\t#[allow(unused)]\n\tpub(crate) fn {} {{\n\t\tmatch {} {{", $fn_sig, if $to_c { "native" } else { "self" }).unwrap(); + for var in e.variants.iter() { + write!(w, "\t\t\t{}{}::{} ", if $to_c { "native" } else { "" }, e.ident, var.ident).unwrap(); + if let syn::Fields::Named(fields) = &var.fields { + write!(w, "{{").unwrap(); + for field in fields.named.iter() { + if export_status(&field.attrs) == ExportStatus::TestOnly { continue; } + write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, field.ident.as_ref().unwrap()).unwrap(); + } + write!(w, "}} ").unwrap(); + } + write!(w, "=>").unwrap(); + if let syn::Fields::Named(fields) = &var.fields { + write!(w, " {{\n\t\t\t\t").unwrap(); + for field in fields.named.iter() { + if export_status(&field.attrs) == ExportStatus::TestOnly { continue; } + let mut sink = ::std::io::sink(); + let mut out: &mut dyn std::io::Write = if $ref { &mut sink } else { w }; + let new_var = if $to_c { + types.write_to_c_conversion_new_var(&mut out, field.ident.as_ref().unwrap(), &field.ty, None, false) + } else { + types.write_from_c_conversion_new_var(&mut out, field.ident.as_ref().unwrap(), &field.ty, None) + }; + if $ref || new_var { + if $ref { + write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", field.ident.as_ref().unwrap(), field.ident.as_ref().unwrap()).unwrap(); + if new_var { + let nonref_ident = syn::Ident::new(&format!("{}_nonref", field.ident.as_ref().unwrap()), Span::call_site()); + if $to_c { + types.write_to_c_conversion_new_var(w, &nonref_ident, &field.ty, None, false); + } else { + types.write_from_c_conversion_new_var(w, &nonref_ident, &field.ty, None); + } + write!(w, "\n\t\t\t\t").unwrap(); + } + } else { + write!(w, "\n\t\t\t\t").unwrap(); + } + } + } + } else { write!(w, " ").unwrap(); } + write!(w, "{}{}::{}", if $to_c { "" } else { "native" }, e.ident, var.ident).unwrap(); + if let syn::Fields::Named(fields) = &var.fields { + write!(w, " {{").unwrap(); + for field in fields.named.iter() { + if export_status(&field.attrs) == ExportStatus::TestOnly { continue; } + write!(w, "\n\t\t\t\t\t{}: ", field.ident.as_ref().unwrap()).unwrap(); + if $to_c { + types.write_to_c_conversion_inline_prefix(w, &field.ty, None, false); + } else { + types.write_from_c_conversion_prefix(w, &field.ty, None); + } + write!(w, "{}{}", + field.ident.as_ref().unwrap(), + if $ref { "_nonref" } else { "" }).unwrap(); + if $to_c { + types.write_to_c_conversion_inline_suffix(w, &field.ty, None, false); + } else { + types.write_from_c_conversion_suffix(w, &field.ty, None); + } + write!(w, ",").unwrap(); + } + writeln!(w, "\n\t\t\t\t}}").unwrap(); + write!(w, "\t\t\t}}").unwrap(); + } + writeln!(w, ",").unwrap(); + } + writeln!(w, "\t\t}}\n\t}}").unwrap(); + } + } + + write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true); + write_conv!(format!("into_native(self) -> native{}", e.ident), false, false); + write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true); + write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false); + writeln!(w, "}}").unwrap(); + + if needs_free { + writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap(); + } + write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free); +} + +fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) { + match export_status(&f.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => return, + } + writeln_docs(w, &f.attrs, ""); + + let mut gen_types = GenericTypes::new(); + if !gen_types.learn_generics(&f.sig.generics, types) { return; } + + write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap(); + write_method_params(w, &f.sig, &HashMap::new(), "", types, Some(&gen_types), false, true); + write!(w, " {{\n\t").unwrap(); + write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false); + write!(w, "{}::{}::{}(", types.orig_crate, types.module_path, f.sig.ident).unwrap(); + write_method_call_params(w, &f.sig, &HashMap::new(), "", types, Some(&gen_types), "", false); + writeln!(w, "\n}}\n").unwrap(); +} + +// ******************************** +// *** File/Crate Walking Logic *** +// ******************************** + +/// Simple utility to walk the modules in a crate - iterating over the modules (with file paths) in +/// a single File. +struct FileIter<'a, I: Iterator> { + in_dir: &'a str, + path: &'a str, + module: &'a str, + item_iter: I, +} +impl<'a, I: Iterator> Iterator for FileIter<'a, I> { + type Item = (String, String, &'a syn::ItemMod); + fn next(&mut self) -> std::option::Option<::Item> { + loop { + match self.item_iter.next() { + Some(syn::Item::Mod(m)) => { + if let syn::Visibility::Public(_) = m.vis { + match export_status(&m.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + + let f_path = format!("{}/{}.rs", (self.path.as_ref() as &Path).parent().unwrap().display(), m.ident); + let new_mod = if self.module.is_empty() { format!("{}", m.ident) } else { format!("{}::{}", self.module, m.ident) }; + if let Ok(_) = File::open(&format!("{}/{}", self.in_dir, f_path)) { + return Some((f_path, new_mod, m)); + } else { + return Some(( + format!("{}/{}/mod.rs", (self.path.as_ref() as &Path).parent().unwrap().display(), m.ident), + new_mod, m)); + } + } + }, + Some(_) => {}, + None => return None, + } + } + } +} +fn file_iter<'a>(file: &'a syn::File, in_dir: &'a str, path: &'a str, module: &'a str) -> + impl Iterator + 'a { + FileIter { in_dir, path, module, item_iter: file.items.iter() } +} + +/// A struct containing the syn::File AST for each file in the crate. +struct FullLibraryAST { + files: HashMap, +} + +/// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at +/// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST +/// at `module` from C. +fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>, in_dir: &str, out_dir: &str, path: &str, orig_crate: &str, module: &str, header_file: &mut File, cpp_header_file: &mut File) { + eprintln!("Converting {}...", path); + + let syntax = if let Some(ast) = libast.files.get(module) { ast } else { return }; + + assert!(syntax.shebang.is_none()); // Not sure what this is, hope we dont have one + + let new_file_path = format!("{}/{}", out_dir, path); + let _ = std::fs::create_dir((&new_file_path.as_ref() as &std::path::Path).parent().unwrap()); + let mut out = std::fs::OpenOptions::new().write(true).create(true).truncate(true) + .open(new_file_path).expect("Unable to open new src file"); + + assert_eq!(export_status(&syntax.attrs), ExportStatus::Export); + writeln_docs(&mut out, &syntax.attrs, ""); + + if path.ends_with("/lib.rs") { + // Special-case the top-level lib.rs with various lint allows and a pointer to the c_types + // and bitcoin hand-written modules. + writeln!(out, "#![allow(unknown_lints)]").unwrap(); + writeln!(out, "#![allow(non_camel_case_types)]").unwrap(); + writeln!(out, "#![allow(non_snake_case)]").unwrap(); + writeln!(out, "#![allow(unused_imports)]").unwrap(); + writeln!(out, "#![allow(unused_variables)]").unwrap(); + writeln!(out, "#![allow(unused_mut)]").unwrap(); + writeln!(out, "#![allow(unused_parens)]").unwrap(); + writeln!(out, "#![allow(unused_unsafe)]").unwrap(); + writeln!(out, "#![allow(unused_braces)]").unwrap(); + writeln!(out, "mod c_types;").unwrap(); + writeln!(out, "mod bitcoin;").unwrap(); + } else { + writeln!(out, "\nuse std::ffi::c_void;\nuse bitcoin::hashes::Hash;\nuse crate::c_types::*;\n").unwrap(); + } + + for (path, new_mod, m) in file_iter(&syntax, in_dir, path, &module) { + writeln_docs(&mut out, &m.attrs, ""); + writeln!(out, "pub mod {};", m.ident).unwrap(); + convert_file(libast, crate_types, in_dir, out_dir, &path, + orig_crate, &new_mod, header_file, cpp_header_file); + } + + let mut type_resolver = TypeResolver::new(orig_crate, module, crate_types); + + for item in syntax.items.iter() { + match item { + syn::Item::Use(u) => type_resolver.process_use(&mut out, &u), + syn::Item::Static(_) => {}, + syn::Item::Enum(e) => { + if let syn::Visibility::Public(_) = e.vis { + writeln_enum(&mut out, &e, &mut type_resolver, header_file, cpp_header_file); + } + }, + syn::Item::Impl(i) => { + writeln_impl(&mut out, &i, &mut type_resolver); + }, + syn::Item::Struct(s) => { + if let syn::Visibility::Public(_) = s.vis { + writeln_struct(&mut out, &s, &mut type_resolver, header_file, cpp_header_file); + } + }, + syn::Item::Trait(t) => { + if let syn::Visibility::Public(_) = t.vis { + writeln_trait(&mut out, &t, &mut type_resolver, header_file, cpp_header_file); + } + }, + syn::Item::Mod(_) => {}, // We don't have to do anything - the top loop handles these. + syn::Item::Const(c) => { + // Re-export any primitive-type constants. + if let syn::Visibility::Public(_) = c.vis { + if let syn::Type::Path(p) = &*c.ty { + let resolved_path = type_resolver.resolve_path(&p.path); + if type_resolver.is_primitive(&resolved_path) { + writeln!(out, "\n#[no_mangle]").unwrap(); + writeln!(out, "pub static {}: {} = {}::{}::{};", c.ident, resolved_path, orig_crate, module, c.ident).unwrap(); + } + } + } + }, + syn::Item::Type(t) => { + if let syn::Visibility::Public(_) = t.vis { + match export_status(&t.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + if t.generics.lt_token.is_none() { + writeln_opaque(&mut out, &t.ident, &format!("{}", t.ident), &t.generics, &t.attrs, &type_resolver, header_file, cpp_header_file); + } + } + }, + syn::Item::Fn(f) => { + if let syn::Visibility::Public(_) = f.vis { + writeln_fn(&mut out, &f, &mut type_resolver); + } + }, + syn::Item::Macro(m) => { + if m.ident.is_none() { // If its not a macro definition + convert_macro(&mut out, &m.mac.path, &m.mac.tokens, &type_resolver); + } + }, + syn::Item::Verbatim(_) => {}, + syn::Item::ExternCrate(_) => {}, + _ => unimplemented!(), + } + } + + out.flush().unwrap(); +} + +/// Load the AST for each file in the crate, filling the FullLibraryAST object +fn load_ast(in_dir: &str, path: &str, module: String, ast_storage: &mut FullLibraryAST) { + eprintln!("Loading {}{}...", in_dir, path); + + let mut file = File::open(format!("{}/{}", in_dir, path)).expect("Unable to open file"); + let mut src = String::new(); + file.read_to_string(&mut src).expect("Unable to read file"); + let syntax = syn::parse_file(&src).expect("Unable to parse file"); + + assert_eq!(export_status(&syntax.attrs), ExportStatus::Export); + + for (path, new_mod, _) in file_iter(&syntax, in_dir, path, &module) { + load_ast(in_dir, &path, new_mod, ast_storage); + } + ast_storage.files.insert(module, syntax); +} + +/// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes. +fn walk_ast<'a>(in_dir: &str, path: &str, module: String, ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) { + let syntax = if let Some(ast) = ast_storage.files.get(&module) { ast } else { return }; + assert_eq!(export_status(&syntax.attrs), ExportStatus::Export); + + for (path, new_mod, _) in file_iter(&syntax, in_dir, path, &module) { + walk_ast(in_dir, &path, new_mod, ast_storage, crate_types); + } + + for item in syntax.items.iter() { + match item { + syn::Item::Struct(s) => { + if let syn::Visibility::Public(_) = s.vis { + match export_status(&s.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + let struct_path = format!("{}::{}", module, s.ident); + crate_types.opaques.insert(struct_path, &s.ident); + } + }, + syn::Item::Trait(t) => { + if let syn::Visibility::Public(_) = t.vis { + match export_status(&t.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + let trait_path = format!("{}::{}", module, t.ident); + crate_types.traits.insert(trait_path, &t); + } + }, + syn::Item::Enum(e) if is_enum_opaque(e) => { + if let syn::Visibility::Public(_) = e.vis { + match export_status(&e.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + let enum_path = format!("{}::{}", module, e.ident); + crate_types.opaques.insert(enum_path, &e.ident); + } + }, + syn::Item::Enum(e) => { + if let syn::Visibility::Public(_) = e.vis { + match export_status(&e.attrs) { + ExportStatus::Export => {}, + ExportStatus::NoExport|ExportStatus::TestOnly => continue, + } + let enum_path = format!("{}::{}", module, e.ident); + crate_types.mirrored_enums.insert(enum_path, &e); + } + }, + _ => {}, + } + } +} + +fn main() { + let args: Vec = env::args().collect(); + if args.len() != 7 { + eprintln!("Usage: source/dir target/dir source_crate_name derived_templates.rs extra/includes.h extra/cpp/includes.hpp"); + process::exit(1); + } + + let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true) + .open(&args[4]).expect("Unable to open new header file"); + let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true) + .open(&args[5]).expect("Unable to open new header file"); + let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true) + .open(&args[6]).expect("Unable to open new header file"); + + writeln!(header_file, "#if defined(__GNUC__)\n#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap(); + writeln!(header_file, "#else\n#define MUST_USE_STRUCT\n#endif").unwrap(); + writeln!(header_file, "#if defined(__GNUC__)\n#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap(); + writeln!(header_file, "#else\n#define MUST_USE_RES\n#endif").unwrap(); + writeln!(cpp_header_file, "#include \nnamespace LDK {{").unwrap(); + + // First parse the full crate's ASTs, caching them so that we can hold references to the AST + // objects in other datastructures: + let mut libast = FullLibraryAST { files: HashMap::new() }; + load_ast(&args[1], "/lib.rs", "".to_string(), &mut libast); + + // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them + // when parsing other file ASTs... + let mut libtypes = CrateTypes { traits: HashMap::new(), opaques: HashMap::new(), mirrored_enums: HashMap::new(), + templates_defined: HashMap::new(), template_file: &mut derived_templates }; + walk_ast(&args[1], "/lib.rs", "".to_string(), &libast, &mut libtypes); + + // ... finally, do the actual file conversion/mapping, writing out types as we go. + convert_file(&libast, &mut libtypes, &args[1], &args[2], "/lib.rs", &args[3], "", &mut header_file, &mut cpp_header_file); + + // For container templates which we created while walking the crate, make sure we add C++ + // mapped types so that C++ users can utilize the auto-destructors available. + for (ty, has_destructor) in libtypes.templates_defined.iter() { + write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor); + } + writeln!(cpp_header_file, "}}").unwrap(); + + header_file.flush().unwrap(); + cpp_header_file.flush().unwrap(); + derived_templates.flush().unwrap(); +} diff --git a/c-bindings-gen/src/types.rs b/c-bindings-gen/src/types.rs new file mode 100644 index 00000000..56bb4e67 --- /dev/null +++ b/c-bindings-gen/src/types.rs @@ -0,0 +1,2021 @@ +use std::collections::HashMap; +use std::fs::File; +use std::io::Write; + +use proc_macro2::{TokenTree, Span}; + +// The following utils are used purely to build our known types maps - they break down all the +// types we need to resolve to include the given object, and no more. + +pub fn first_seg_self<'a>(t: &'a syn::Type) -> Option + 'a> { + match t { + syn::Type::Path(p) => { + if p.qself.is_some() || p.path.leading_colon.is_some() { + return None; + } + let mut segs = p.path.segments.iter(); + let ty = segs.next().unwrap(); + if !ty.arguments.is_empty() { return None; } + if format!("{}", ty.ident) == "Self" { + Some(segs) + } else { None } + }, + _ => None, + } +} + +pub fn get_single_remaining_path_seg<'a, I: Iterator>(segs: &mut I) -> Option<&'a syn::Ident> { + if let Some(ty) = segs.next() { + if !ty.arguments.is_empty() { unimplemented!(); } + if segs.next().is_some() { return None; } + Some(&ty.ident) + } else { None } +} + +pub fn assert_single_path_seg<'a>(p: &'a syn::Path) -> &'a syn::Ident { + if p.leading_colon.is_some() { unimplemented!(); } + get_single_remaining_path_seg(&mut p.segments.iter()).unwrap() +} + +pub fn single_ident_generic_path_to_ident(p: &syn::Path) -> Option<&syn::Ident> { + if p.segments.len() == 1 { + Some(&p.segments.iter().next().unwrap().ident) + } else { None } +} + +#[derive(Debug, PartialEq)] +pub enum ExportStatus { + Export, + NoExport, + TestOnly, +} +/// Gets the ExportStatus of an object (struct, fn, etc) given its attributes. +pub fn export_status(attrs: &[syn::Attribute]) -> ExportStatus { + for attr in attrs.iter() { + let tokens_clone = attr.tokens.clone(); + let mut token_iter = tokens_clone.into_iter(); + if let Some(token) = token_iter.next() { + match token { + TokenTree::Punct(c) if c.as_char() == '=' => { + // Really not sure where syn gets '=' from here - + // it somehow represents '///' or '//!' + }, + TokenTree::Group(g) => { + if format!("{}", single_ident_generic_path_to_ident(&attr.path).unwrap()) == "cfg" { + let mut iter = g.stream().into_iter(); + if let TokenTree::Ident(i) = iter.next().unwrap() { + if i == "any" { + // #[cfg(any(test, feature = ""))] + if let TokenTree::Group(g) = iter.next().unwrap() { + if let TokenTree::Ident(i) = g.stream().into_iter().next().unwrap() { + if i == "test" || i == "feature" { + // If its cfg(feature(...)) we assume its test-only + return ExportStatus::TestOnly; + } + } + } + } else if i == "test" || i == "feature" { + // If its cfg(feature(...)) we assume its test-only + return ExportStatus::TestOnly; + } + } + } + continue; // eg #[derive()] + }, + _ => unimplemented!(), + } + } else { continue; } + match token_iter.next().unwrap() { + TokenTree::Literal(lit) => { + let line = format!("{}", lit); + if line.contains("(C-not exported)") { + return ExportStatus::NoExport; + } + }, + _ => unimplemented!(), + } + } + ExportStatus::Export +} + +pub fn assert_simple_bound(bound: &syn::TraitBound) { + if bound.paren_token.is_some() || bound.lifetimes.is_some() { unimplemented!(); } + if let syn::TraitBoundModifier::Maybe(_) = bound.modifier { unimplemented!(); } +} + +/// A stack of sets of generic resolutions. +/// +/// This tracks the template parameters for a function, struct, or trait, allowing resolution into +/// a concrete type. By pushing a new context onto the stack, this can track a function's template +/// parameters inside of a generic struct or trait. +/// +/// It maps both direct types as well as Deref, mapping them via the provided +/// TypeResolver's resolve_path function (ie traits map to the concrete jump table, structs to the +/// concrete C container struct, etc). +pub struct GenericTypes<'a> { + typed_generics: Vec)>>, +} +impl<'a> GenericTypes<'a> { + pub fn new() -> Self { + Self { typed_generics: vec![HashMap::new()], } + } + + /// push a new context onto the stack, allowing for a new set of generics to be learned which + /// will override any lower contexts, but which will still fall back to resoltion via lower + /// contexts. + pub fn push_ctx(&mut self) { + self.typed_generics.push(HashMap::new()); + } + /// pop the latest context off the stack. + pub fn pop_ctx(&mut self) { + self.typed_generics.pop(); + } + + /// Learn the generics in generics in the current context, given a TypeResolver. + pub fn learn_generics<'b, 'c>(&mut self, generics: &'a syn::Generics, types: &'b TypeResolver<'a, 'c>) -> bool { + for generic in generics.params.iter() { + match generic { + syn::GenericParam::Type(type_param) => { + let mut non_lifetimes_processed = false; + for bound in type_param.bounds.iter() { + if let syn::TypeParamBound::Trait(trait_bound) = bound { + if let Some(ident) = single_ident_generic_path_to_ident(&trait_bound.path) { + match &format!("{}", ident) as &str { "Send" => continue, "Sync" => continue, _ => {} } + } + + assert_simple_bound(&trait_bound); + if let Some(mut path) = types.maybe_resolve_path(&trait_bound.path) { + if types.skip_path(&path) { continue; } + if non_lifetimes_processed { return false; } + non_lifetimes_processed = true; + let new_ident = if path != "std::ops::Deref" { + path = "crate::".to_string() + &path; + Some(&trait_bound.path) + } else { None }; + self.typed_generics.last_mut().unwrap().insert(&type_param.ident, (path, new_ident)); + } else { return false; } + } + } + }, + _ => {}, + } + } + if let Some(wh) = &generics.where_clause { + for pred in wh.predicates.iter() { + if let syn::WherePredicate::Type(t) = pred { + if let syn::Type::Path(p) = &t.bounded_ty { + if p.qself.is_some() { return false; } + if p.path.leading_colon.is_some() { return false; } + let mut p_iter = p.path.segments.iter(); + if let Some(gen) = self.typed_generics.last_mut().unwrap().get_mut(&p_iter.next().unwrap().ident) { + if gen.0 != "std::ops::Deref" { return false; } + if &format!("{}", p_iter.next().unwrap().ident) != "Target" { return false; } + + let mut non_lifetimes_processed = false; + for bound in t.bounds.iter() { + if let syn::TypeParamBound::Trait(trait_bound) = bound { + if non_lifetimes_processed { return false; } + non_lifetimes_processed = true; + assert_simple_bound(&trait_bound); + *gen = ("crate::".to_string() + &types.resolve_path(&trait_bound.path), + Some(&trait_bound.path)); + } + } + } else { return false; } + } else { return false; } + } + } + } + for (_, (_, ident)) in self.typed_generics.last().unwrap().iter() { + if ident.is_none() { return false; } + } + true + } + + /// Attempt to resolve an Ident as a generic parameter and return the full path. + pub fn maybe_resolve_ident<'b>(&'b self, ident: &syn::Ident) -> Option<&'b String> { + for gen in self.typed_generics.iter().rev() { + if let Some(res) = gen.get(ident).map(|(a, _)| a) { + return Some(res); + } + } + None + } + /// Attempt to resolve a Path as a generic parameter and return the full path. as both a string + /// and syn::Path. + pub fn maybe_resolve_path<'b>(&'b self, path: &syn::Path) -> Option<(&'b String, &'a syn::Path)> { + if let Some(ident) = path.get_ident() { + for gen in self.typed_generics.iter().rev() { + if let Some(res) = gen.get(ident).map(|(a, b)| (a, b.unwrap())) { + return Some(res); + } + } + } + None + } +} + +#[derive(Clone, PartialEq)] +// The type of declaration and the object itself +pub enum DeclType<'a> { + MirroredEnum, + Trait(&'a syn::ItemTrait), + StructImported, + StructIgnored, + EnumIgnored, +} + +/// Top-level struct tracking everything which has been defined while walking the crate. +pub struct CrateTypes<'a> { + /// This may contain structs or enums, but only when either is mapped as + /// struct X { inner: *mut originalX, .. } + pub opaques: HashMap, + /// Enums which are mapped as C enums with conversion functions + pub mirrored_enums: HashMap, + /// Traits which are mapped as a pointer + jump table + pub traits: HashMap, + /// Template continer types defined, map from mangled type name -> whether a destructor fn + /// exists. + /// + /// This is used at the end of processing to make C++ wrapper classes + pub templates_defined: HashMap, + /// The output file for any created template container types, written to as we find new + /// template containers which need to be defined. + pub template_file: &'a mut File, +} + +/// A struct which tracks resolving rust types into C-mapped equivalents, exists for one specific +/// module but contains a reference to the overall CrateTypes tracking. +pub struct TypeResolver<'mod_lifetime, 'crate_lft: 'mod_lifetime> { + pub orig_crate: &'mod_lifetime str, + pub module_path: &'mod_lifetime str, + imports: HashMap, + // ident -> is-mirrored-enum + declared: HashMap>, + pub crate_types: &'mod_lifetime mut CrateTypes<'crate_lft>, +} + +impl<'a, 'c: 'a> TypeResolver<'a, 'c> { + pub fn new(orig_crate: &'a str, module_path: &'a str, crate_types: &'a mut CrateTypes<'c>) -> Self { + let mut imports = HashMap::new(); + // Add primitives to the "imports" list: + imports.insert(syn::Ident::new("bool", Span::call_site()), "bool".to_string()); + imports.insert(syn::Ident::new("u64", Span::call_site()), "u64".to_string()); + imports.insert(syn::Ident::new("u32", Span::call_site()), "u32".to_string()); + imports.insert(syn::Ident::new("u16", Span::call_site()), "u16".to_string()); + imports.insert(syn::Ident::new("u8", Span::call_site()), "u8".to_string()); + imports.insert(syn::Ident::new("usize", Span::call_site()), "usize".to_string()); + imports.insert(syn::Ident::new("str", Span::call_site()), "str".to_string()); + imports.insert(syn::Ident::new("String", Span::call_site()), "String".to_string()); + + // These are here to allow us to print native Rust types in trait fn impls even if we don't + // have C mappings: + imports.insert(syn::Ident::new("Result", Span::call_site()), "Result".to_string()); + imports.insert(syn::Ident::new("Vec", Span::call_site()), "Vec".to_string()); + imports.insert(syn::Ident::new("Option", Span::call_site()), "Option".to_string()); + Self { orig_crate, module_path, imports, declared: HashMap::new(), crate_types } + } + + // ************************************************* + // *** Well know type and conversion definitions *** + // ************************************************* + + /// Returns true we if can just skip passing this to C entirely + fn skip_path(&self, full_path: &str) -> bool { + full_path == "bitcoin::secp256k1::Secp256k1" || + full_path == "bitcoin::secp256k1::Signing" || + full_path == "bitcoin::secp256k1::Verification" + } + /// Returns true we if can just skip passing this to C entirely + fn no_arg_path_to_rust(&self, full_path: &str) -> &str { + if full_path == "bitcoin::secp256k1::Secp256k1" { + "&bitcoin::secp256k1::Secp256k1::new()" + } else { unimplemented!(); } + } + + /// Returns true if the object is a primitive and is mapped as-is with no conversion + /// whatsoever. + pub fn is_primitive(&self, full_path: &str) -> bool { + match full_path { + "bool" => true, + "u64" => true, + "u32" => true, + "u16" => true, + "u8" => true, + "usize" => true, + _ => false, + } + } + /// Gets the C-mapped type for types which are outside of the crate, or which are manually + /// ignored by for some reason need mapping anyway. + fn c_type_from_path<'b>(&self, full_path: &'b str, is_ref: bool, ptr_for_ref: bool) -> Option<&'b str> { + if self.is_primitive(full_path) { + return Some(full_path); + } + match full_path { + "Result" => Some("crate::c_types::derived::CResult"), + "Vec" if !is_ref => Some("crate::c_types::derived::CVec"), + "Option" => Some(""), + + // Note that no !is_ref types can map to an array because Rust and C's call semantics + // for arrays are different (https://github.com/eqrion/cbindgen/issues/528) + + "[u8; 32]" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "[u8; 16]" if !is_ref => Some("crate::c_types::SixteenBytes"), + "[u8; 10]" if !is_ref => Some("crate::c_types::TenBytes"), + "[u8; 4]" if !is_ref => Some("crate::c_types::FourBytes"), + "[u8; 3]" if !is_ref => Some("crate::c_types::ThreeBytes"), // Used for RGB values + + "str" if is_ref => Some("crate::c_types::Str"), + "String" if !is_ref => Some("crate::c_types::derived::CVec_u8Z"), + "String" if is_ref => Some("crate::c_types::Str"), + + "std::time::Duration" => Some("u64"), + + "bitcoin::secp256k1::key::PublicKey" => Some("crate::c_types::PublicKey"), + "bitcoin::secp256k1::Signature" => Some("crate::c_types::Signature"), + "bitcoin::secp256k1::key::SecretKey" if is_ref => Some("*const [u8; 32]"), + "bitcoin::secp256k1::key::SecretKey" if !is_ref => Some("crate::c_types::SecretKey"), + "bitcoin::secp256k1::Error" if !is_ref => Some("crate::c_types::Secp256k1Error"), + "bitcoin::blockdata::script::Script" if is_ref => Some("crate::c_types::u8slice"), + "bitcoin::blockdata::script::Script" if !is_ref => Some("crate::c_types::derived::CVec_u8Z"), + "bitcoin::blockdata::transaction::OutPoint" if is_ref => Some("crate::chain::transaction::OutPoint"), + "bitcoin::blockdata::transaction::Transaction" if is_ref && !ptr_for_ref => Some("crate::c_types::Transaction"), + "bitcoin::blockdata::transaction::Transaction" => Some("crate::c_types::derived::CVec_u8Z"), + "bitcoin::blockdata::transaction::TxOut" if !is_ref => Some("crate::c_types::TxOut"), + "bitcoin::OutPoint" => Some("crate::chain::transaction::OutPoint"), + "bitcoin::network::constants::Network" => Some("crate::bitcoin::network::Network"), + "bitcoin::blockdata::block::BlockHeader" if is_ref => Some("*const [u8; 80]"), + "bitcoin::blockdata::block::Block" if is_ref => Some("crate::c_types::u8slice"), + + // Newtypes that we just expose in their original form. + "bitcoin::hash_types::Txid" if is_ref => Some("*const [u8; 32]"), + "bitcoin::hash_types::Txid" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "bitcoin::hash_types::BlockHash" if is_ref => Some("*const [u8; 32]"), + "bitcoin::hash_types::BlockHash" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "ln::channelmanager::PaymentHash" if is_ref => Some("*const [u8; 32]"), + "ln::channelmanager::PaymentHash" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "ln::channelmanager::PaymentPreimage" if is_ref => Some("*const [u8; 32]"), + "ln::channelmanager::PaymentPreimage" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "ln::channelmanager::PaymentSecret" if is_ref => Some("crate::c_types::ThirtyTwoBytes"), + "ln::channelmanager::PaymentSecret" if !is_ref => Some("crate::c_types::ThirtyTwoBytes"), + + // Override the default since Records contain an fmt with a lifetime: + "util::logger::Record" => Some("*const std::os::raw::c_char"), + + // List of structs we map that aren't detected: + "ln::features::InitFeatures" if is_ref && ptr_for_ref => Some("crate::ln::features::InitFeatures"), + "ln::features::InitFeatures" if is_ref => Some("*const crate::ln::features::InitFeatures"), + "ln::features::InitFeatures" => Some("crate::ln::features::InitFeatures"), + _ => { + eprintln!(" Type {} (ref: {}) unresolvable in C", full_path, is_ref); + None + }, + } + } + + fn from_c_conversion_new_var_from_path<'b>(&self, _full_path: &str, _is_ref: bool) -> Option<(&'b str, &'b str)> { + None + } + fn from_c_conversion_prefix_from_path<'b>(&self, full_path: &str, is_ref: bool) -> Option { + if self.is_primitive(full_path) { + return Some("".to_owned()); + } + match full_path { + "Vec" if !is_ref => Some("local_"), + "Result" if !is_ref => Some("local_"), + "Option" if is_ref => Some("&local_"), + "Option" => Some("local_"), + + "[u8; 32]" if is_ref => Some("unsafe { &*"), + "[u8; 32]" if !is_ref => Some(""), + "[u8; 16]" if !is_ref => Some(""), + "[u8; 10]" if !is_ref => Some(""), + "[u8; 4]" if !is_ref => Some(""), + "[u8; 3]" if !is_ref => Some(""), + + "[u8]" if is_ref => Some(""), + "[usize]" if is_ref => Some(""), + + "str" if is_ref => Some(""), + "String" if !is_ref => Some("String::from_utf8("), + // Note that we'll panic for String if is_ref, as we only have non-owned memory, we + // cannot create a &String. + + "std::time::Duration" => Some("std::time::Duration::from_secs("), + + "bitcoin::secp256k1::key::PublicKey" if is_ref => Some("&"), + "bitcoin::secp256k1::key::PublicKey" => Some(""), + "bitcoin::secp256k1::Signature" if is_ref => Some("&"), + "bitcoin::secp256k1::Signature" => Some(""), + "bitcoin::secp256k1::key::SecretKey" if is_ref => Some("&::bitcoin::secp256k1::key::SecretKey::from_slice(&unsafe { *"), + "bitcoin::secp256k1::key::SecretKey" if !is_ref => Some(""), + "bitcoin::blockdata::script::Script" if is_ref => Some("&::bitcoin::blockdata::script::Script::from(Vec::from("), + "bitcoin::blockdata::script::Script" if !is_ref => Some("::bitcoin::blockdata::script::Script::from("), + "bitcoin::blockdata::transaction::Transaction" if is_ref => Some("&"), + "bitcoin::blockdata::transaction::Transaction" => Some("::bitcoin::consensus::encode::deserialize(&"), + "bitcoin::blockdata::transaction::TxOut" if !is_ref => Some(""), + "bitcoin::network::constants::Network" => Some(""), + "bitcoin::blockdata::block::BlockHeader" => Some("&::bitcoin::consensus::encode::deserialize(unsafe { &*"), + "bitcoin::blockdata::block::Block" if is_ref => Some("&::bitcoin::consensus::encode::deserialize("), + + // Newtypes that we just expose in their original form. + "bitcoin::hash_types::Txid" if is_ref => Some("&::bitcoin::hash_types::Txid::from_slice(&unsafe { &*"), + "bitcoin::hash_types::Txid" if !is_ref => Some("::bitcoin::hash_types::Txid::from_slice(&"), + "bitcoin::hash_types::BlockHash" => Some("::bitcoin::hash_types::BlockHash::from_slice(&"), + "ln::channelmanager::PaymentHash" if !is_ref => Some("::lightning::ln::channelmanager::PaymentHash("), + "ln::channelmanager::PaymentHash" if is_ref => Some("&::lightning::ln::channelmanager::PaymentHash(unsafe { *"), + "ln::channelmanager::PaymentPreimage" if !is_ref => Some("::lightning::ln::channelmanager::PaymentPreimage("), + "ln::channelmanager::PaymentPreimage" if is_ref => Some("&::lightning::ln::channelmanager::PaymentPreimage(unsafe { *"), + "ln::channelmanager::PaymentSecret" => Some("::lightning::ln::channelmanager::PaymentSecret("), + + // List of structs we map (possibly during processing of other files): + "ln::features::InitFeatures" if !is_ref => Some("*unsafe { Box::from_raw("), + + // List of traits we map (possibly during processing of other files): + "crate::util::logger::Logger" => Some(""), + + _ => { + eprintln!(" Type {} unconvertable from C", full_path); + None + }, + }.map(|s| s.to_owned()) + } + fn from_c_conversion_suffix_from_path<'b>(&self, full_path: &str, is_ref: bool) -> Option { + if self.is_primitive(full_path) { + return Some("".to_owned()); + } + match full_path { + "Vec" if !is_ref => Some(""), + "Option" => Some(""), + "Result" if !is_ref => Some(""), + + "[u8; 32]" if is_ref => Some("}"), + "[u8; 32]" if !is_ref => Some(".data"), + "[u8; 16]" if !is_ref => Some(".data"), + "[u8; 10]" if !is_ref => Some(".data"), + "[u8; 4]" if !is_ref => Some(".data"), + "[u8; 3]" if !is_ref => Some(".data"), + + "[u8]" if is_ref => Some(".to_slice()"), + "[usize]" if is_ref => Some(".to_slice()"), + + "str" if is_ref => Some(".into()"), + "String" if !is_ref => Some(".into_rust()).unwrap()"), + + "std::time::Duration" => Some(")"), + + "bitcoin::secp256k1::key::PublicKey" => Some(".into_rust()"), + "bitcoin::secp256k1::Signature" => Some(".into_rust()"), + "bitcoin::secp256k1::key::SecretKey" if !is_ref => Some(".into_rust()"), + "bitcoin::secp256k1::key::SecretKey" if is_ref => Some("}[..]).unwrap()"), + "bitcoin::blockdata::script::Script" if is_ref => Some(".to_slice()))"), + "bitcoin::blockdata::script::Script" if !is_ref => Some(".into_rust())"), + "bitcoin::blockdata::transaction::Transaction" if is_ref => Some(".into_bitcoin()"), + "bitcoin::blockdata::transaction::Transaction" => Some(".into_rust()[..]).unwrap()"), + "bitcoin::blockdata::transaction::TxOut" if !is_ref => Some(".into_rust()"), + "bitcoin::network::constants::Network" => Some(".into_bitcoin()"), + "bitcoin::blockdata::block::BlockHeader" => Some(" }).unwrap()"), + "bitcoin::blockdata::block::Block" => Some(".to_slice()).unwrap()"), + + // Newtypes that we just expose in their original form. + "bitcoin::hash_types::Txid" if is_ref => Some(" }[..]).unwrap()"), + "bitcoin::hash_types::Txid" => Some(".data[..]).unwrap()"), + "bitcoin::hash_types::BlockHash" if !is_ref => Some(".data[..]).unwrap()"), + "ln::channelmanager::PaymentHash" if !is_ref => Some(".data)"), + "ln::channelmanager::PaymentHash" if is_ref => Some(" })"), + "ln::channelmanager::PaymentPreimage" if !is_ref => Some(".data)"), + "ln::channelmanager::PaymentPreimage" if is_ref => Some(" })"), + "ln::channelmanager::PaymentSecret" => Some(".data)"), + + // List of structs we map (possibly during processing of other files): + "ln::features::InitFeatures" if is_ref => Some(".inner) }"), + "ln::features::InitFeatures" if !is_ref => Some(".take_ptr()) }"), + + // List of traits we map (possibly during processing of other files): + "crate::util::logger::Logger" => Some(""), + + _ => { + eprintln!(" Type {} unconvertable from C", full_path); + None + }, + }.map(|s| s.to_owned()) + } + + fn to_c_conversion_new_var_from_path<'b>(&self, full_path: &str, is_ref: bool) -> Option<(&'b str, &'b str)> { + if self.is_primitive(full_path) { + return None; + } + match full_path { + "[u8]" if is_ref => Some(("crate::c_types::u8slice::from_slice(", ")")), + "[usize]" if is_ref => Some(("crate::c_types::usizeslice::from_slice(", ")")), + + "bitcoin::blockdata::transaction::Transaction" if is_ref => Some(("::bitcoin::consensus::encode::serialize(", ")")), + "bitcoin::blockdata::transaction::Transaction" if !is_ref => Some(("::bitcoin::consensus::encode::serialize(&", ")")), + "bitcoin::blockdata::block::BlockHeader" if is_ref => Some(("{ let mut s = [0u8; 80]; s[..].copy_from_slice(&::bitcoin::consensus::encode::serialize(", ")); s }")), + "bitcoin::blockdata::block::Block" if is_ref => Some(("::bitcoin::consensus::encode::serialize(", ")")), + "bitcoin::hash_types::Txid" => None, + + // Override the default since Records contain an fmt with a lifetime: + // TODO: We should include the other record fields + "util::logger::Record" => Some(("std::ffi::CString::new(format!(\"{}\", ", ".args)).unwrap()")), + _ => None, + }.map(|s| s.to_owned()) + } + fn to_c_conversion_inline_prefix_from_path(&self, full_path: &str, is_ref: bool, ptr_for_ref: bool) -> Option { + if self.is_primitive(full_path) { + return Some("".to_owned()); + } + match full_path { + "Result" if !is_ref => Some("local_"), + "Vec" if !is_ref => Some("local_"), + "Option" => Some("local_"), + + "[u8; 32]" if !is_ref => Some("crate::c_types::ThirtyTwoBytes { data: "), + "[u8; 32]" if is_ref => Some("&"), + "[u8; 16]" if !is_ref => Some("crate::c_types::SixteenBytes { data: "), + "[u8; 10]" if !is_ref => Some("crate::c_types::TenBytes { data: "), + "[u8; 4]" if !is_ref => Some("crate::c_types::FourBytes { data: "), + "[u8; 3]" if is_ref => Some("&"), + + "[u8]" if is_ref => Some("local_"), + "[usize]" if is_ref => Some("local_"), + + "str" if is_ref => Some(""), + "String" => Some(""), + + "std::time::Duration" => Some(""), + + "bitcoin::secp256k1::key::PublicKey" => Some("crate::c_types::PublicKey::from_rust(&"), + "bitcoin::secp256k1::Signature" => Some("crate::c_types::Signature::from_rust(&"), + "bitcoin::secp256k1::key::SecretKey" if is_ref => Some(""), + "bitcoin::secp256k1::key::SecretKey" if !is_ref => Some("crate::c_types::SecretKey::from_rust("), + "bitcoin::secp256k1::Error" if !is_ref => Some("crate::c_types::Secp256k1Error::from_rust("), + "bitcoin::blockdata::script::Script" if is_ref => Some("crate::c_types::u8slice::from_slice(&"), + "bitcoin::blockdata::script::Script" if !is_ref => Some(""), + "bitcoin::blockdata::transaction::Transaction" if is_ref && !ptr_for_ref => Some("crate::c_types::Transaction::from_slice(&local_"), + "bitcoin::blockdata::transaction::Transaction" => Some("local_"), + "bitcoin::blockdata::transaction::TxOut" if !is_ref => Some("crate::c_types::TxOut::from_rust("), + "bitcoin::blockdata::block::BlockHeader" if is_ref => Some("&local_"), + "bitcoin::blockdata::block::Block" if is_ref => Some("crate::c_types::u8slice::from_slice(&local_"), + + "bitcoin::hash_types::Txid" if !is_ref => Some("crate::c_types::ThirtyTwoBytes { data: "), + + // Newtypes that we just expose in their original form. + "bitcoin::hash_types::Txid" if is_ref => Some(""), + "bitcoin::hash_types::BlockHash" if is_ref => Some(""), + "bitcoin::hash_types::BlockHash" => Some("crate::c_types::ThirtyTwoBytes { data: "), + "ln::channelmanager::PaymentHash" if is_ref => Some("&"), + "ln::channelmanager::PaymentHash" if !is_ref => Some("crate::c_types::ThirtyTwoBytes { data: "), + "ln::channelmanager::PaymentPreimage" if is_ref => Some("&"), + "ln::channelmanager::PaymentPreimage" => Some("crate::c_types::ThirtyTwoBytes { data: "), + "ln::channelmanager::PaymentSecret" if !is_ref => Some("crate::c_types::ThirtyTwoBytes { data: "), + + // Override the default since Records contain an fmt with a lifetime: + "util::logger::Record" => Some("local_"), + + // List of structs we map (possibly during processing of other files): + "ln::features::InitFeatures" if is_ref && ptr_for_ref => Some("crate::ln::features::InitFeatures { inner: &mut "), + "ln::features::InitFeatures" if is_ref => Some("Box::into_raw(Box::new(crate::ln::features::InitFeatures { inner: &mut "), + "ln::features::InitFeatures" if !is_ref => Some("crate::ln::features::InitFeatures { inner: Box::into_raw(Box::new("), + + _ => { + eprintln!(" Type {} (is_ref: {}) unconvertable to C", full_path, is_ref); + None + }, + }.map(|s| s.to_owned()) + } + fn to_c_conversion_inline_suffix_from_path(&self, full_path: &str, is_ref: bool, ptr_for_ref: bool) -> Option { + if self.is_primitive(full_path) { + return Some("".to_owned()); + } + match full_path { + "Result" if !is_ref => Some(""), + "Vec" if !is_ref => Some(".into()"), + "Option" => Some(""), + + "[u8; 32]" if !is_ref => Some(" }"), + "[u8; 32]" if is_ref => Some(""), + "[u8; 16]" if !is_ref => Some(" }"), + "[u8; 10]" if !is_ref => Some(" }"), + "[u8; 4]" if !is_ref => Some(" }"), + "[u8; 3]" if is_ref => Some(""), + + "[u8]" if is_ref => Some(""), + "[usize]" if is_ref => Some(""), + + "str" if is_ref => Some(".into()"), + "String" if !is_ref => Some(".into_bytes().into()"), + "String" if is_ref => Some(".as_str().into()"), + + "std::time::Duration" => Some(".as_secs()"), + + "bitcoin::secp256k1::key::PublicKey" => Some(")"), + "bitcoin::secp256k1::Signature" => Some(")"), + "bitcoin::secp256k1::key::SecretKey" if !is_ref => Some(")"), + "bitcoin::secp256k1::key::SecretKey" if is_ref => Some(".as_ref()"), + "bitcoin::secp256k1::Error" if !is_ref => Some(")"), + "bitcoin::blockdata::script::Script" if is_ref => Some("[..])"), + "bitcoin::blockdata::script::Script" if !is_ref => Some(".into_bytes().into()"), + "bitcoin::blockdata::transaction::Transaction" if is_ref && !ptr_for_ref => Some(")"), + "bitcoin::blockdata::transaction::Transaction" => Some(".into()"), + "bitcoin::blockdata::transaction::TxOut" if !is_ref => Some(")"), + "bitcoin::blockdata::block::BlockHeader" if is_ref => Some(""), + "bitcoin::blockdata::block::Block" if is_ref => Some(")"), + + "bitcoin::hash_types::Txid" if !is_ref => Some(".into_inner() }"), + + // Newtypes that we just expose in their original form. + "bitcoin::hash_types::Txid" if is_ref => Some(".as_inner()"), + "bitcoin::hash_types::BlockHash" if is_ref => Some(".as_inner()"), + "bitcoin::hash_types::BlockHash" => Some(".into_inner() }"), + "ln::channelmanager::PaymentHash" if is_ref => Some(".0"), + "ln::channelmanager::PaymentHash" => Some(".0 }"), + "ln::channelmanager::PaymentPreimage" if is_ref => Some(".0"), + "ln::channelmanager::PaymentPreimage" => Some(".0 }"), + "ln::channelmanager::PaymentSecret" if !is_ref => Some(".0 }"), + + // Override the default since Records contain an fmt with a lifetime: + "util::logger::Record" => Some(".as_ptr()"), + + // List of structs we map (possibly during processing of other files): + "ln::features::InitFeatures" if is_ref && ptr_for_ref => Some(", is_owned: false }"), + "ln::features::InitFeatures" if is_ref => Some(", is_owned: false }))"), + "ln::features::InitFeatures" => Some(")), is_owned: true }"), + + _ => { + eprintln!(" Type {} unconvertable to C", full_path); + None + }, + }.map(|s| s.to_owned()) + } + + fn empty_val_check_suffix_from_path(&self, full_path: &str) -> Option<&str> { + match full_path { + "ln::channelmanager::PaymentSecret" => Some(".data == [0; 32]"), + _ => None + } + } + + // **************************** + // *** Container Processing *** + // **************************** + + /// Returns the module path in the generated mapping crate to the containers which we generate + /// when writing to CrateTypes::template_file. + fn generated_container_path() -> &'static str { + "crate::c_types::derived" + } + /// Returns the module path in the generated mapping crate to the container templates, which + /// are then concretized and put in the generated container path/template_file. + fn container_templ_path() -> &'static str { + "crate::c_types" + } + + /// Returns true if this is a "transparent" container, ie an Option or a container which does + /// not require a generated continer class. + fn is_transparent_container(&self, full_path: &str, _is_ref: bool) -> bool { + full_path == "Option" + } + /// Returns true if this is a known, supported, non-transparent container. + fn is_known_container(&self, full_path: &str, is_ref: bool) -> bool { + (full_path == "Result" && !is_ref) || (full_path == "Vec" && !is_ref) || full_path.ends_with("Tuple") + } + fn to_c_conversion_container_new_var<'b>(&self, full_path: &str, is_ref: bool, single_contained: Option<&syn::Type>, var_name: &syn::Ident, var_access: &str) + // Returns prefix + Vec<(prefix, var-name-to-inline-convert)> + suffix + // expecting one element in the vec per generic type, each of which is inline-converted + -> Option<(&'b str, Vec<(String, String)>, &'b str)> { + match full_path { + "Result" if !is_ref => { + Some(("match ", + vec![(" { Ok(mut o) => crate::c_types::CResultTempl::ok(".to_string(), "o".to_string()), + ("), Err(mut e) => crate::c_types::CResultTempl::err(".to_string(), "e".to_string())], + ") }")) + }, + "Vec" if !is_ref => { + Some(("Vec::new(); for item in ", vec![(format!(".drain(..) {{ local_{}.push(", var_name), "item".to_string())], "); }")) + }, + "Slice" => { + Some(("Vec::new(); for item in ", vec![(format!(".iter() {{ local_{}.push(", var_name), "**item".to_string())], "); }")) + }, + "Option" => { + if let Some(syn::Type::Path(p)) = single_contained { + if self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) { + if is_ref { + return Some(("if ", vec![ + (".is_none() { std::ptr::null() } else { ".to_owned(), format!("({}.as_ref().unwrap())", var_access)) + ], " }")); + } else { + return Some(("if ", vec![ + (".is_none() { std::ptr::null_mut() } else { ".to_owned(), format!("({}.unwrap())", var_access)) + ], " }")); + } + } + } + if let Some(t) = single_contained { + let mut v = Vec::new(); + self.write_empty_rust_val(&mut v, t); + let s = String::from_utf8(v).unwrap(); + return Some(("if ", vec![ + (format!(".is_none() {{ {} }} else {{ ", s), format!("({}.unwrap())", var_access)) + ], " }")); + } else { unreachable!(); } + }, + _ => None, + } + } + + /// only_contained_has_inner implies that there is only one contained element in the container + /// and it has an inner field (ie is an "opaque" type we've defined). + fn from_c_conversion_container_new_var<'b>(&self, full_path: &str, is_ref: bool, single_contained: Option<&syn::Type>, var_name: &syn::Ident, var_access: &str) + // Returns prefix + Vec<(prefix, var-name-to-inline-convert)> + suffix + // expecting one element in the vec per generic type, each of which is inline-converted + -> Option<(&'b str, Vec<(String, String)>, &'b str)> { + match full_path { + "Result" if !is_ref => { + Some(("match ", + vec![(".result_ok { true => Ok(".to_string(), format!("(*unsafe {{ Box::from_raw({}.contents.result.take_ptr()) }})", var_name)), + ("), false => Err(".to_string(), format!("(*unsafe {{ Box::from_raw({}.contents.err.take_ptr()) }})", var_name))], + ")}")) + }, + "Vec"|"Slice" if !is_ref => { + Some(("Vec::new(); for mut item in ", vec![(format!(".into_rust().drain(..) {{ local_{}.push(", var_name), "item".to_string())], "); }")) + }, + "Slice" if is_ref => { + Some(("Vec::new(); for mut item in ", vec![(format!(".as_slice().iter() {{ local_{}.push(", var_name), "item".to_string())], "); }")) + }, + "Option" => { + if let Some(syn::Type::Path(p)) = single_contained { + if self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) { + if is_ref { + return Some(("if ", vec![(".inner.is_null() { None } else { Some((*".to_string(), format!("{}", var_name))], ").clone()) }")) + } else { + return Some(("if ", vec![(".inner.is_null() { None } else { Some(".to_string(), format!("{}", var_name))], ") }")); + } + } + } + + if let Some(t) = single_contained { + let mut v = Vec::new(); + let needs_deref = self.write_empty_rust_val_check_suffix(&mut v, t); + let s = String::from_utf8(v).unwrap(); + if needs_deref { + return Some(("if ", vec![ + (format!("{} {{ None }} else {{ Some(", s), format!("unsafe {{ &mut *{} }}", var_access)) + ], ") }")); + } else { + return Some(("if ", vec![ + (format!("{} {{ None }} else {{ Some(", s), format!("{}", var_access)) + ], ") }")); + } + } else { unreachable!(); } + }, + _ => None, + } + } + + // ************************************************* + // *** Type definition during main.rs processing *** + // ************************************************* + + fn process_use_intern(&mut self, w: &mut W, u: &syn::UseTree, partial_path: &str) { + match u { + syn::UseTree::Path(p) => { + let new_path = format!("{}::{}", partial_path, p.ident); + self.process_use_intern(w, &p.tree, &new_path); + }, + syn::UseTree::Name(n) => { + let full_path = format!("{}::{}", partial_path, n.ident); + self.imports.insert(n.ident.clone(), full_path); + }, + syn::UseTree::Group(g) => { + for i in g.items.iter() { + self.process_use_intern(w, i, partial_path); + } + }, + syn::UseTree::Rename(r) => { + let full_path = format!("{}::{}", partial_path, r.ident); + self.imports.insert(r.rename.clone(), full_path); + }, + syn::UseTree::Glob(_) => { + eprintln!("Ignoring * use for {} - this may result in resolution failures", partial_path); + }, + } + } + pub fn process_use(&mut self, w: &mut W, u: &syn::ItemUse) { + if let syn::Visibility::Public(_) = u.vis { + // We actually only use these for #[cfg(fuzztarget)] + eprintln!("Ignoring pub(use) tree!"); + return; + } + match &u.tree { + syn::UseTree::Path(p) => { + let new_path = format!("{}", p.ident); + self.process_use_intern(w, &p.tree, &new_path); + }, + _ => unimplemented!(), + } + if u.leading_colon.is_some() { unimplemented!() } + } + + pub fn mirrored_enum_declared(&mut self, ident: &syn::Ident) { + eprintln!("{} mirrored", ident); + self.declared.insert(ident.clone(), DeclType::MirroredEnum); + } + pub fn enum_ignored(&mut self, ident: &'c syn::Ident) { + self.declared.insert(ident.clone(), DeclType::EnumIgnored); + } + pub fn struct_imported(&mut self, ident: &'c syn::Ident, named: String) { + eprintln!("Imported {} as {}", ident, named); + self.declared.insert(ident.clone(), DeclType::StructImported); + } + pub fn struct_ignored(&mut self, ident: &syn::Ident) { + eprintln!("Not importing {}", ident); + self.declared.insert(ident.clone(), DeclType::StructIgnored); + } + pub fn trait_declared(&mut self, ident: &syn::Ident, t: &'c syn::ItemTrait) { + eprintln!("Trait {} created", ident); + self.declared.insert(ident.clone(), DeclType::Trait(t)); + } + pub fn get_declared_type(&'a self, ident: &syn::Ident) -> Option<&'a DeclType<'c>> { + self.declared.get(ident) + } + /// Returns true if the object at the given path is mapped as X { inner: *mut origX, .. }. + fn c_type_has_inner_from_path(&self, full_path: &str) -> bool{ + self.crate_types.opaques.get(full_path).is_some() + } + + pub fn maybe_resolve_ident(&self, id: &syn::Ident) -> Option { + if let Some(imp) = self.imports.get(id) { + Some(imp.clone()) + } else if self.declared.get(id).is_some() { + Some(self.module_path.to_string() + "::" + &format!("{}", id)) + } else { None } + } + + pub fn maybe_resolve_non_ignored_ident(&self, id: &syn::Ident) -> Option { + if let Some(imp) = self.imports.get(id) { + Some(imp.clone()) + } else if let Some(decl_type) = self.declared.get(id) { + match decl_type { + DeclType::StructIgnored => None, + _ => Some(self.module_path.to_string() + "::" + &format!("{}", id)), + } + } else { None } + } + + pub fn maybe_resolve_path(&self, p: &syn::Path) -> Option { + if p.leading_colon.is_some() { + // At some point we may need this, but for now, its unused, so just fail. + return None; + } else if let Some(id) = p.get_ident() { + self.maybe_resolve_ident(id) + } else { + if p.segments.len() == 1 { + let seg = p.segments.iter().next().unwrap(); + return self.maybe_resolve_ident(&seg.ident); + } + let mut seg_iter = p.segments.iter(); + let first_seg = seg_iter.next().unwrap(); + let remaining: String = seg_iter.map(|seg| { + if let syn::PathArguments::None = seg.arguments { + format!("{}", seg.ident) + } else { + format!("{}", seg.ident) + } + }).collect(); + if let Some(imp) = self.imports.get(&first_seg.ident) { + if remaining != "" { + Some(imp.clone() + "::" + &remaining) + } else { + Some(imp.clone()) + } + } else { None } + } + } + pub fn resolve_path(&self, p: &syn::Path) -> String { + self.maybe_resolve_path(p).unwrap() + } + + // *********************************** + // *** Original Rust Type Printing *** + // *********************************** + + fn write_rust_path(&self, w: &mut W, path: &syn::Path) { + if let Some(resolved) = self.maybe_resolve_path(&path) { + if self.is_primitive(&resolved) { + write!(w, "{}", path.get_ident().unwrap()).unwrap(); + } else { + if resolved.starts_with("ln::") || resolved.starts_with("chain::") || resolved.starts_with("util::") { + write!(w, "lightning::{}", resolved).unwrap(); + } else { + write!(w, "{}", resolved).unwrap(); // XXX: Probably doens't work, get_ident().unwrap() + } + } + if let syn::PathArguments::AngleBracketed(args) = &path.segments.iter().last().unwrap().arguments { + self.write_rust_generic_arg(w, args.args.iter()); + } + } else { + if path.leading_colon.is_some() { + write!(w, "::").unwrap(); + } + for (idx, seg) in path.segments.iter().enumerate() { + if idx != 0 { write!(w, "::").unwrap(); } + write!(w, "{}", seg.ident).unwrap(); + if let syn::PathArguments::AngleBracketed(args) = &seg.arguments { + self.write_rust_generic_arg(w, args.args.iter()); + } + } + } + } + pub fn write_rust_generic_param<'b, W: std::io::Write>(&self, w: &mut W, generics: impl Iterator) { + let mut had_params = false; + for (idx, arg) in generics.enumerate() { + if idx != 0 { write!(w, ", ").unwrap(); } else { write!(w, "<").unwrap(); } + had_params = true; + match arg { + syn::GenericParam::Lifetime(lt) => write!(w, "'{}", lt.lifetime.ident).unwrap(), + syn::GenericParam::Type(t) => { + write!(w, "{}", t.ident).unwrap(); + if t.colon_token.is_some() { write!(w, ":").unwrap(); } + for (idx, bound) in t.bounds.iter().enumerate() { + if idx != 0 { write!(w, " + ").unwrap(); } + match bound { + syn::TypeParamBound::Trait(tb) => { + if tb.paren_token.is_some() || tb.lifetimes.is_some() { unimplemented!(); } + self.write_rust_path(w, &tb.path); + }, + _ => unimplemented!(), + } + } + if t.eq_token.is_some() || t.default.is_some() { unimplemented!(); } + }, + _ => unimplemented!(), + } + } + if had_params { write!(w, ">").unwrap(); } + } + + pub fn write_rust_generic_arg<'b, W: std::io::Write>(&self, w: &mut W, generics: impl Iterator) { + write!(w, "<").unwrap(); + for (idx, arg) in generics.enumerate() { + if idx != 0 { write!(w, ", ").unwrap(); } + match arg { + syn::GenericArgument::Type(t) => self.write_rust_type(w, t), + _ => unimplemented!(), + } + } + write!(w, ">").unwrap(); + } + pub fn write_rust_type(&self, w: &mut W, t: &syn::Type) { + match t { + syn::Type::Path(p) => { + if p.qself.is_some() || p.path.leading_colon.is_some() { + unimplemented!(); + } + self.write_rust_path(w, &p.path); + }, + syn::Type::Reference(r) => { + write!(w, "&").unwrap(); + if let Some(lft) = &r.lifetime { + write!(w, "'{} ", lft.ident).unwrap(); + } + if r.mutability.is_some() { + write!(w, "mut ").unwrap(); + } + self.write_rust_type(w, &*r.elem); + }, + syn::Type::Array(a) => { + write!(w, "[").unwrap(); + self.write_rust_type(w, &a.elem); + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + write!(w, "; {}]", i).unwrap(); + } else { unimplemented!(); } + } else { unimplemented!(); } + } + syn::Type::Slice(s) => { + write!(w, "[").unwrap(); + self.write_rust_type(w, &s.elem); + write!(w, "]").unwrap(); + }, + syn::Type::Tuple(s) => { + write!(w, "(").unwrap(); + for (idx, t) in s.elems.iter().enumerate() { + if idx != 0 { write!(w, ", ").unwrap(); } + self.write_rust_type(w, &t); + } + write!(w, ")").unwrap(); + }, + _ => unimplemented!(), + } + } + + /// Prints a constructor for something which is "uninitialized" (but obviously not actually + /// unint'd memory). + pub fn write_empty_rust_val(&self, w: &mut W, t: &syn::Type) { + match t { + syn::Type::Path(p) => { + let resolved = self.resolve_path(&p.path); + if self.crate_types.opaques.get(&resolved).is_some() { + write!(w, "crate::{} {{ inner: std::ptr::null_mut(), is_owned: true }}", resolved).unwrap(); + } else { + // Assume its a manually-mapped C type, where we can just define an null() fn + write!(w, "{}::null()", self.c_type_from_path(&resolved, false, false).unwrap()).unwrap(); + } + }, + syn::Type::Array(a) => { + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + if i.base10_digits().parse::().unwrap() < 32 { + // Blindly assume that if we're trying to create an empty value for an + // array < 32 entries that all-0s may be a valid state. + unimplemented!(); + } + let arrty = format!("[u8; {}]", i.base10_digits()); + write!(w, "{}", self.to_c_conversion_inline_prefix_from_path(&arrty, false, false).unwrap()).unwrap(); + write!(w, "[0; {}]", i.base10_digits()).unwrap(); + write!(w, "{}", self.to_c_conversion_inline_suffix_from_path(&arrty, false, false).unwrap()).unwrap(); + } else { unimplemented!(); } + } else { unimplemented!(); } + } + _ => unimplemented!(), + } + } + + /// Prints a suffix to determine if a variable is empty (ie was set by write_empty_rust_val), + /// returning whether we need to dereference the inner value before using it (ie it is a + /// pointer). + pub fn write_empty_rust_val_check_suffix(&self, w: &mut W, t: &syn::Type) -> bool { + match t { + syn::Type::Path(p) => { + let resolved = self.resolve_path(&p.path); + if self.crate_types.opaques.get(&resolved).is_some() { + write!(w, ".inner.is_null()").unwrap(); + false + } else { + if let Some(suffix) = self.empty_val_check_suffix_from_path(&resolved) { + write!(w, "{}", suffix).unwrap(); + false // We may eventually need to allow empty_val_check_suffix_from_path to specify if we need a deref or not + } else { + write!(w, ".is_null()").unwrap(); + false + } + } + }, + syn::Type::Array(a) => { + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + write!(w, " == [0; {}]", i.base10_digits()).unwrap(); + false + } else { unimplemented!(); } + } else { unimplemented!(); } + }, + syn::Type::Slice(_) => { + // Option<[]> always implies that we want to treat len() == 0 differently from + // None, so we always map an Option<[]> into a pointer. + write!(w, ".is_null()").unwrap(); + true + }, + _ => unimplemented!(), + } + } + + /// Prints a suffix to determine if a variable is empty (ie was set by write_empty_rust_val). + pub fn write_empty_rust_val_check(&self, w: &mut W, t: &syn::Type, var_access: &str) { + match t { + syn::Type::Path(_) => { + write!(w, "{}", var_access).unwrap(); + self.write_empty_rust_val_check_suffix(w, t); + }, + syn::Type::Array(a) => { + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + let arrty = format!("[u8; {}]", i.base10_digits()); + // We don't (yet) support a new-var conversion here. + assert!(self.from_c_conversion_new_var_from_path(&arrty, false).is_none()); + write!(w, "{}{}{}", + self.from_c_conversion_prefix_from_path(&arrty, false).unwrap(), + var_access, + self.from_c_conversion_suffix_from_path(&arrty, false).unwrap()).unwrap(); + self.write_empty_rust_val_check_suffix(w, t); + } else { unimplemented!(); } + } else { unimplemented!(); } + } + _ => unimplemented!(), + } + } + + // ******************************** + // *** Type conversion printing *** + // ******************************** + + /// Returns true we if can just skip passing this to C entirely + pub fn skip_arg(&self, t: &syn::Type, generics: Option<&GenericTypes>) -> bool { + match t { + syn::Type::Path(p) => { + if p.qself.is_some() { unimplemented!(); } + if let Some(gen_types) = generics { + if let Some(resolved) = gen_types.maybe_resolve_path(&p.path) { + return self.skip_path(resolved.0); + } + } + if let Some(full_path) = self.maybe_resolve_path(&p.path) { + self.skip_path(&full_path) + } else { false } + }, + syn::Type::Reference(r) => { + self.skip_arg(&*r.elem, generics) + }, + _ => false, + } + } + pub fn no_arg_to_rust(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>) { + match t { + syn::Type::Path(p) => { + if p.qself.is_some() { unimplemented!(); } + if let Some(gen_types) = generics { + if let Some(resolved) = gen_types.maybe_resolve_path(&p.path) { + write!(w, "{}", self.no_arg_path_to_rust(resolved.0)).unwrap(); + return; + } + } + if let Some(full_path) = self.maybe_resolve_path(&p.path) { + write!(w, "{}", self.no_arg_path_to_rust(&full_path)).unwrap(); + } + }, + syn::Type::Reference(r) => { + self.no_arg_to_rust(w, &*r.elem, generics); + }, + _ => {}, + } + } + + fn write_conversion_inline_intern Option, DL: Fn(&mut W, &DeclType, &str, bool, bool), SC: Fn(bool) -> &'static str> + (&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, is_ref: bool, is_mut: bool, ptr_for_ref: bool, + tupleconv: &str, prefix: bool, sliceconv: SC, path_lookup: LP, decl_lookup: DL) { + match t { + syn::Type::Reference(r) => { + self.write_conversion_inline_intern(w, &*r.elem, generics, true, r.mutability.is_some(), + ptr_for_ref, tupleconv, prefix, sliceconv, path_lookup, decl_lookup); + }, + syn::Type::Path(p) => { + if p.qself.is_some() || p.path.leading_colon.is_some() { + unimplemented!(); + } + + if let Some(gen_types) = generics { + if let Some((_, synpath)) = gen_types.maybe_resolve_path(&p.path) { + let genpath = self.resolve_path(&synpath); + assert!(!self.is_known_container(&genpath, is_ref) && !self.is_transparent_container(&genpath, is_ref)); + if let Some(c_type) = path_lookup(&genpath, is_ref, ptr_for_ref) { + write!(w, "{}", c_type).unwrap(); + return; + } else { + let synident = single_ident_generic_path_to_ident(synpath).unwrap(); + if let Some(t) = self.crate_types.traits.get(&genpath) { + decl_lookup(w, &DeclType::Trait(t), &genpath, is_ref, is_mut); + return; + } else if let Some(_) = self.imports.get(synident) { + // crate_types lookup has to have succeeded: + panic!("Failed to print inline conversion for {}", synident); + } else if let Some(decl_type) = self.declared.get(synident) { + decl_lookup(w, decl_type, &self.maybe_resolve_path(synpath).unwrap(), is_ref, is_mut); + return; + } else { unimplemented!(); } + } + } + } + + let resolved_path = self.resolve_path(&p.path); + if let Some(c_type) = path_lookup(&resolved_path, is_ref, ptr_for_ref) { + write!(w, "{}", c_type).unwrap(); + } else if self.crate_types.opaques.get(&resolved_path).is_some() { + decl_lookup(w, &DeclType::StructImported, &resolved_path, is_ref, is_mut); + } else if self.crate_types.mirrored_enums.get(&resolved_path).is_some() { + decl_lookup(w, &DeclType::MirroredEnum, &resolved_path, is_ref, is_mut); + } else if let Some(ident) = single_ident_generic_path_to_ident(&p.path) { + if let Some(_) = self.imports.get(ident) { + // crate_types lookup has to have succeeded: + panic!("Failed to print inline conversion for {}", ident); + } else if let Some(decl_type) = self.declared.get(ident) { + decl_lookup(w, decl_type, &self.maybe_resolve_ident(ident).unwrap(), is_ref, is_mut); + } else { unimplemented!(); } + } + }, + syn::Type::Array(a) => { + // We assume all arrays contain only [int_literal; X]s. + // This may result in some outputs not compiling. + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + write!(w, "{}", path_lookup(&format!("[u8; {}]", i.base10_digits()), is_ref, ptr_for_ref).unwrap()).unwrap(); + } else { unimplemented!(); } + } else { unimplemented!(); } + }, + syn::Type::Slice(s) => { + // We assume all slices contain only literals or references. + // This may result in some outputs not compiling. + if let syn::Type::Path(p) = &*s.elem { + let resolved = self.resolve_path(&p.path); + assert!(self.is_primitive(&resolved)); + write!(w, "{}", path_lookup("[u8]", is_ref, ptr_for_ref).unwrap()).unwrap(); + } else if let syn::Type::Reference(r) = &*s.elem { + if let syn::Type::Path(p) = &*r.elem { + write!(w, "{}", sliceconv(self.c_type_has_inner_from_path(&self.resolve_path(&p.path)))).unwrap(); + } else { unimplemented!(); } + } else { unimplemented!(); } + }, + syn::Type::Tuple(t) => { + if t.elems.is_empty() { + // cbindgen has poor support for (), see, eg https://github.com/eqrion/cbindgen/issues/527 + // so work around it by just pretending its a 0u8 + write!(w, "{}", tupleconv).unwrap(); + } else { + if prefix { write!(w, "local_").unwrap(); } + } + }, + _ => unimplemented!(), + } + } + + fn write_to_c_conversion_inline_prefix_inner(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, is_ref: bool, ptr_for_ref: bool, from_ptr: bool) { + self.write_conversion_inline_intern(w, t, generics, is_ref, false, ptr_for_ref, "0u8 /*", true, |_| "local_", + |a, b, c| self.to_c_conversion_inline_prefix_from_path(a, b, c), + |w, decl_type, decl_path, is_ref, _is_mut| { + match decl_type { + DeclType::MirroredEnum if is_ref && ptr_for_ref => write!(w, "crate::{}::from_native(&", decl_path).unwrap(), + DeclType::MirroredEnum if is_ref => write!(w, "&crate::{}::from_native(&", decl_path).unwrap(), + DeclType::MirroredEnum => write!(w, "crate::{}::native_into(", decl_path).unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref && ptr_for_ref && from_ptr => + write!(w, "crate::{} {{ inner: unsafe {{ (", decl_path).unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref && ptr_for_ref => + write!(w, "crate::{} {{ inner: unsafe {{ ( (&(", decl_path).unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref => + write!(w, "&crate::{} {{ inner: unsafe {{ (", decl_path).unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if !is_ref && from_ptr => + write!(w, "crate::{} {{ inner: ", decl_path).unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if !is_ref => + write!(w, "crate::{} {{ inner: Box::into_raw(Box::new(", decl_path).unwrap(), + DeclType::Trait(_) if is_ref => write!(w, "&").unwrap(), + _ => panic!("{:?}", decl_path), + } + }); + } + pub fn write_to_c_conversion_inline_prefix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, ptr_for_ref: bool) { + self.write_to_c_conversion_inline_prefix_inner(w, t, generics, false, ptr_for_ref, false); + } + fn write_to_c_conversion_inline_suffix_inner(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, is_ref: bool, ptr_for_ref: bool, from_ptr: bool) { + self.write_conversion_inline_intern(w, t, generics, is_ref, false, ptr_for_ref, "*/", false, |_| ".into()", + |a, b, c| self.to_c_conversion_inline_suffix_from_path(a, b, c), + |w, decl_type, _full_path, is_ref, _is_mut| match decl_type { + DeclType::MirroredEnum => write!(w, ")").unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref && ptr_for_ref && from_ptr => + write!(w, " as *const _) as *mut _ }}, is_owned: false }}").unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref && ptr_for_ref => + write!(w, ") as *const _) as *mut _) }}, is_owned: false }}").unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if is_ref => + write!(w, " as *const _) as *mut _ }}, is_owned: false }}").unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if !is_ref && from_ptr => + write!(w, ", is_owned: true }}").unwrap(), + DeclType::EnumIgnored|DeclType::StructImported if !is_ref => write!(w, ")), is_owned: true }}").unwrap(), + DeclType::Trait(_) if is_ref => {}, + _ => unimplemented!(), + }); + } + pub fn write_to_c_conversion_inline_suffix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, ptr_for_ref: bool) { + self.write_to_c_conversion_inline_suffix_inner(w, t, generics, false, ptr_for_ref, false); + } + + fn write_from_c_conversion_prefix_inner(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, is_ref: bool, ptr_for_ref: bool) { + self.write_conversion_inline_intern(w, t, generics, is_ref, false, false, "() /*", true, |_| "&local_", + |a, b, _c| self.from_c_conversion_prefix_from_path(a, b), + |w, decl_type, _full_path, is_ref, is_mut| match decl_type { + DeclType::StructImported if is_ref && ptr_for_ref => write!(w, "unsafe {{ &*(*").unwrap(), + DeclType::StructImported if is_mut && is_ref => write!(w, "unsafe {{ &mut *").unwrap(), + DeclType::StructImported if is_ref => write!(w, "unsafe {{ &*").unwrap(), + DeclType::StructImported if !is_ref => write!(w, "*unsafe {{ Box::from_raw(").unwrap(), + DeclType::MirroredEnum if is_ref => write!(w, "&").unwrap(), + DeclType::MirroredEnum => {}, + DeclType::Trait(_) => {}, + _ => unimplemented!(), + }); + } + pub fn write_from_c_conversion_prefix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>) { + self.write_from_c_conversion_prefix_inner(w, t, generics, false, false); + } + fn write_from_c_conversion_suffix_inner(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, is_ref: bool, ptr_for_ref: bool) { + self.write_conversion_inline_intern(w, t, generics, is_ref, false, false, "*/", false, + |has_inner| match has_inner { + false => ".iter().collect::>()[..]", + true => "[..]", + }, + |a, b, _c| self.from_c_conversion_suffix_from_path(a, b), + |w, decl_type, _full_path, is_ref, _is_mut| match decl_type { + DeclType::StructImported if is_ref && ptr_for_ref => write!(w, ").inner }}").unwrap(), + DeclType::StructImported if is_ref => write!(w, ".inner }}").unwrap(), + DeclType::StructImported if !is_ref => write!(w, ".take_ptr()) }}").unwrap(), + DeclType::MirroredEnum if is_ref => write!(w, ".to_native()").unwrap(), + DeclType::MirroredEnum => write!(w, ".into_native()").unwrap(), + DeclType::Trait(_) => {}, + _ => unimplemented!(), + }); + } + pub fn write_from_c_conversion_suffix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>) { + self.write_from_c_conversion_suffix_inner(w, t, generics, false, false); + } + // Note that compared to the above conversion functions, the following two are generally + // significantly undertested: + pub fn write_from_c_conversion_to_ref_prefix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>) { + self.write_conversion_inline_intern(w, t, generics, false, false, false, "() /*", true, |_| "&local_", + |a, b, _c| { + if let Some(conv) = self.from_c_conversion_prefix_from_path(a, b) { + Some(format!("&{}", conv)) + } else { None } + }, + |w, decl_type, _full_path, is_ref, _is_mut| match decl_type { + DeclType::StructImported if !is_ref => write!(w, "unsafe {{ &*").unwrap(), + _ => unimplemented!(), + }); + } + pub fn write_from_c_conversion_to_ref_suffix(&self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>) { + self.write_conversion_inline_intern(w, t, generics, false, false, false, "*/", false, + |has_inner| match has_inner { + false => ".iter().collect::>()[..]", + true => "[..]", + }, + |a, b, _c| self.from_c_conversion_suffix_from_path(a, b), + |w, decl_type, _full_path, is_ref, _is_mut| match decl_type { + DeclType::StructImported if !is_ref => write!(w, ".inner }}").unwrap(), + _ => unimplemented!(), + }); + } + + fn write_conversion_new_var_intern<'b, W: std::io::Write, + LP: Fn(&str, bool) -> Option<(&str, &str)>, + LC: Fn(&str, bool, Option<&syn::Type>, &syn::Ident, &str) -> Option<(&'b str, Vec<(String, String)>, &'b str)>, + VP: Fn(&mut W, &syn::Type, Option<&GenericTypes>, bool, bool, bool), + VS: Fn(&mut W, &syn::Type, Option<&GenericTypes>, bool, bool, bool)> + (&self, w: &mut W, ident: &syn::Ident, var: &str, t: &syn::Type, generics: Option<&GenericTypes>, + mut is_ref: bool, mut ptr_for_ref: bool, to_c: bool, + path_lookup: &LP, container_lookup: &LC, var_prefix: &VP, var_suffix: &VS) -> bool { + + macro_rules! convert_container { + ($container_type: expr, $args_len: expr, $args_iter: expr) => { { + // For slices (and Options), we refuse to directly map them as is_ref when they + // aren't opaque types containing an inner pointer. This is due to the fact that, + // in both cases, the actual higher-level type is non-is_ref. + let ty_has_inner = if self.is_transparent_container(&$container_type, is_ref) || $container_type == "Slice" { + let ty = $args_iter().next().unwrap(); + if $container_type == "Slice" && to_c { + // "To C ptr_for_ref" means "return the regular object with is_owned + // set to false", which is totally what we want in a slice if we're about to + // set ty_has_inner. + ptr_for_ref = true; + } + if let syn::Type::Reference(t) = ty { + if let syn::Type::Path(p) = &*t.elem { + self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) + } else { false } + } else if let syn::Type::Path(p) = ty { + self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) + } else { false } + } else { true }; + + // Options get a bunch of special handling, since in general we map Option<>al + // types into the same C type as non-Option-wrapped types. This ends up being + // pretty manual here and most of the below special-cases are for Options. + let mut needs_ref_map = false; + let mut only_contained_type = None; + let mut only_contained_has_inner = false; + let mut contains_slice = false; + if $args_len == 1 && self.is_transparent_container(&$container_type, is_ref) { + only_contained_has_inner = ty_has_inner; + let arg = $args_iter().next().unwrap(); + if let syn::Type::Reference(t) = arg { + only_contained_type = Some(&*t.elem); + if let syn::Type::Path(_) = &*t.elem { + is_ref = true; + } else if let syn::Type::Slice(_) = &*t.elem { + contains_slice = true; + } else { return false; } + needs_ref_map = true; + } else if let syn::Type::Path(_) = arg { + only_contained_type = Some(&arg); + } else { unimplemented!(); } + } + + if let Some((prefix, conversions, suffix)) = container_lookup(&$container_type, is_ref && ty_has_inner, only_contained_type, ident, var) { + assert_eq!(conversions.len(), $args_len); + write!(w, "let mut local_{}{} = ", ident, if !to_c && needs_ref_map {"_base"} else { "" }).unwrap(); + if only_contained_has_inner && to_c { + var_prefix(w, $args_iter().next().unwrap(), generics, is_ref, ptr_for_ref, true); + } + write!(w, "{}{}", prefix, var).unwrap(); + + for ((pfx, var_name), (idx, ty)) in conversions.iter().zip($args_iter().enumerate()) { + let mut var = std::io::Cursor::new(Vec::new()); + write!(&mut var, "{}", var_name).unwrap(); + let var_access = String::from_utf8(var.into_inner()).unwrap(); + + let conv_ty = if needs_ref_map { only_contained_type.as_ref().unwrap() } else { ty }; + + write!(w, "{} {{ ", pfx).unwrap(); + let new_var_name = format!("{}_{}", ident, idx); + let new_var = self.write_conversion_new_var_intern(w, &syn::Ident::new(&new_var_name, Span::call_site()), + &var_access, conv_ty, generics, contains_slice || (is_ref && ty_has_inner), ptr_for_ref, to_c, path_lookup, container_lookup, var_prefix, var_suffix); + if new_var { write!(w, " ").unwrap(); } + if (!only_contained_has_inner || !to_c) && !contains_slice { + var_prefix(w, conv_ty, generics, is_ref && ty_has_inner, ptr_for_ref, false); + } + + if !is_ref && !needs_ref_map && to_c && only_contained_has_inner { + write!(w, "Box::into_raw(Box::new(").unwrap(); + } + write!(w, "{}{}", if contains_slice { "local_" } else { "" }, if new_var { new_var_name } else { var_access }).unwrap(); + if (!only_contained_has_inner || !to_c) && !contains_slice { + var_suffix(w, conv_ty, generics, is_ref && ty_has_inner, ptr_for_ref, false); + } + if !is_ref && !needs_ref_map && to_c && only_contained_has_inner { + write!(w, "))").unwrap(); + } + write!(w, " }}").unwrap(); + } + write!(w, "{}", suffix).unwrap(); + if only_contained_has_inner && to_c { + var_suffix(w, $args_iter().next().unwrap(), generics, is_ref, ptr_for_ref, true); + } + write!(w, ";").unwrap(); + if !to_c && needs_ref_map { + write!(w, " let mut local_{} = local_{}_base.as_ref()", ident, ident).unwrap(); + if contains_slice { + write!(w, ".map(|a| &a[..])").unwrap(); + } + write!(w, ";").unwrap(); + } + return true; + } + } } + } + + match t { + syn::Type::Reference(r) => { + if let syn::Type::Slice(_) = &*r.elem { + self.write_conversion_new_var_intern(w, ident, var, &*r.elem, generics, is_ref, ptr_for_ref, to_c, path_lookup, container_lookup, var_prefix, var_suffix) + } else { + self.write_conversion_new_var_intern(w, ident, var, &*r.elem, generics, true, ptr_for_ref, to_c, path_lookup, container_lookup, var_prefix, var_suffix) + } + }, + syn::Type::Path(p) => { + if p.qself.is_some() || p.path.leading_colon.is_some() { + unimplemented!(); + } + if let Some(gen_types) = generics { + if let Some(resolved) = gen_types.maybe_resolve_path(&p.path) { + assert!(!self.is_known_container(&resolved.0, is_ref) && !self.is_transparent_container(&resolved.0, is_ref)); + if let Some((prefix, suffix)) = path_lookup(&resolved.0, is_ref) { + write!(w, "let mut local_{} = {}{}{};", ident, prefix, var, suffix).unwrap(); + return true; + } else { return false; } + } + } + let resolved_path = self.resolve_path(&p.path); + if self.is_known_container(&resolved_path, is_ref) || self.is_transparent_container(&resolved_path, is_ref) { + if let syn::PathArguments::AngleBracketed(args) = &p.path.segments.iter().next().unwrap().arguments { + convert_container!(resolved_path, args.args.len(), || args.args.iter().map(|arg| { + if let syn::GenericArgument::Type(ty) = arg { + ty + } else { unimplemented!(); } + })); + } else { unimplemented!(); } + } + if self.is_primitive(&resolved_path) { + false + } else if let Some(ty_ident) = single_ident_generic_path_to_ident(&p.path) { + if let Some((prefix, suffix)) = path_lookup(&resolved_path, is_ref) { + write!(w, "let mut local_{} = {}{}{};", ident, prefix, var, suffix).unwrap(); + true + } else if self.declared.get(ty_ident).is_some() { + false + } else { false } + } else { false } + }, + syn::Type::Array(_) => { + // We assume all arrays contain only primitive types. + // This may result in some outputs not compiling. + false + }, + syn::Type::Slice(s) => { + if let syn::Type::Path(p) = &*s.elem { + let resolved = self.resolve_path(&p.path); + assert!(self.is_primitive(&resolved)); + let slice_path = format!("[{}]", resolved); + if let Some((prefix, suffix)) = path_lookup(&slice_path, true) { + write!(w, "let mut local_{} = {}{}{};", ident, prefix, var, suffix).unwrap(); + true + } else { false } + } else if let syn::Type::Reference(ty) = &*s.elem { + let tyref = [&*ty.elem]; + is_ref = true; + convert_container!("Slice", 1, || tyref.iter()); + unimplemented!("convert_container should return true as container_lookup should succeed for slices"); + } else { unimplemented!() } + }, + syn::Type::Tuple(t) => { + if !t.elems.is_empty() { + // We don't (yet) support tuple elements which cannot be converted inline + write!(w, "let (").unwrap(); + for idx in 0..t.elems.len() { + if idx != 0 { write!(w, ", ").unwrap(); } + write!(w, "{} orig_{}_{}", if is_ref { "ref" } else { "mut" }, ident, idx).unwrap(); + } + write!(w, ") = {}{}; ", var, if !to_c { ".to_rust()" } else { "" }).unwrap(); + // Like other template types, tuples are always mapped as their non-ref + // versions for types which have different ref mappings. Thus, we convert to + // non-ref versions and handle opaque types with inner pointers manually. + for (idx, elem) in t.elems.iter().enumerate() { + if let syn::Type::Path(p) = elem { + let v_name = format!("orig_{}_{}", ident, idx); + let tuple_elem_ident = syn::Ident::new(&v_name, Span::call_site()); + if self.write_conversion_new_var_intern(w, &tuple_elem_ident, &v_name, elem, generics, + false, ptr_for_ref, to_c, + path_lookup, container_lookup, var_prefix, var_suffix) { + write!(w, " ").unwrap(); + // Opaque types with inner pointers shouldn't ever create new stack + // variables, so we don't handle it and just assert that it doesn't + // here. + assert!(!self.c_type_has_inner_from_path(&self.resolve_path(&p.path))); + } + } + } + write!(w, "let mut local_{} = (", ident).unwrap(); + for (idx, elem) in t.elems.iter().enumerate() { + let ty_has_inner = { + if to_c { + // "To C ptr_for_ref" means "return the regular object with + // is_owned set to false", which is totally what we want + // if we're about to set ty_has_inner. + ptr_for_ref = true; + } + if let syn::Type::Reference(t) = elem { + if let syn::Type::Path(p) = &*t.elem { + self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) + } else { false } + } else if let syn::Type::Path(p) = elem { + self.c_type_has_inner_from_path(&self.resolve_path(&p.path)) + } else { false } + }; + if idx != 0 { write!(w, ", ").unwrap(); } + var_prefix(w, elem, generics, is_ref && ty_has_inner, ptr_for_ref, false); + if is_ref && ty_has_inner { + // For ty_has_inner, the regular var_prefix mapping will take a + // reference, so deref once here to make sure we keep the original ref. + write!(w, "*").unwrap(); + } + write!(w, "orig_{}_{}", ident, idx).unwrap(); + if is_ref && !ty_has_inner { + // If we don't have an inner variable's reference to maintain, just + // hope the type is Clonable and use that. + write!(w, ".clone()").unwrap(); + } + var_suffix(w, elem, generics, is_ref && ty_has_inner, ptr_for_ref, false); + } + write!(w, "){};", if to_c { ".into()" } else { "" }).unwrap(); + true + } else { false } + }, + _ => unimplemented!(), + } + } + + pub fn write_to_c_conversion_new_var_inner(&self, w: &mut W, ident: &syn::Ident, var_access: &str, t: &syn::Type, generics: Option<&GenericTypes>, ptr_for_ref: bool) -> bool { + self.write_conversion_new_var_intern(w, ident, var_access, t, generics, false, ptr_for_ref, true, + &|a, b| self.to_c_conversion_new_var_from_path(a, b), + &|a, b, c, d, e| self.to_c_conversion_container_new_var(a, b, c, d, e), + // We force ptr_for_ref here since we can't generate a ref on one line and use it later + &|a, b, c, d, e, f| self.write_to_c_conversion_inline_prefix_inner(a, b, c, d, e, f), + &|a, b, c, d, e, f| self.write_to_c_conversion_inline_suffix_inner(a, b, c, d, e, f)) + } + pub fn write_to_c_conversion_new_var(&self, w: &mut W, ident: &syn::Ident, t: &syn::Type, generics: Option<&GenericTypes>, ptr_for_ref: bool) -> bool { + self.write_to_c_conversion_new_var_inner(w, ident, &format!("{}", ident), t, generics, ptr_for_ref) + } + pub fn write_from_c_conversion_new_var(&self, w: &mut W, ident: &syn::Ident, t: &syn::Type, generics: Option<&GenericTypes>) -> bool { + self.write_conversion_new_var_intern(w, ident, &format!("{}", ident), t, generics, false, false, false, + &|a, b| self.from_c_conversion_new_var_from_path(a, b), + &|a, b, c, d, e| self.from_c_conversion_container_new_var(a, b, c, d, e), + // We force ptr_for_ref here since we can't generate a ref on one line and use it later + &|a, b, c, d, e, _f| self.write_from_c_conversion_prefix_inner(a, b, c, d, e), + &|a, b, c, d, e, _f| self.write_from_c_conversion_suffix_inner(a, b, c, d, e)) + } + + // ****************************************************** + // *** C Container Type Equivalent and alias Printing *** + // ****************************************************** + + fn write_template_constructor(&mut self, w: &mut W, container_type: &str, mangled_container: &str, args: &Vec<&syn::Type>, is_ref: bool) { + if container_type == "Result" { + assert_eq!(args.len(), 2); + macro_rules! write_fn { + ($call: expr) => { { + writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}() -> {} {{", mangled_container, $call, mangled_container).unwrap(); + writeln!(w, "\t{}::CResultTempl::{}(0)\n}}\n", Self::container_templ_path(), $call).unwrap(); + } } + } + macro_rules! write_alias { + ($call: expr, $item: expr) => { { + write!(w, "#[no_mangle]\npub static {}_{}: extern \"C\" fn (", mangled_container, $call).unwrap(); + if let syn::Type::Path(syn::TypePath { path, .. }) = $item { + let resolved = self.resolve_path(path); + if self.is_known_container(&resolved, is_ref) || self.is_transparent_container(&resolved, is_ref) { + self.write_c_mangled_container_path_intern(w, Self::path_to_generic_args(path), + &format!("{}", single_ident_generic_path_to_ident(path).unwrap()), is_ref, false, false, false); + } else { + self.write_template_generics(w, &mut [$item].iter().map(|t| *t), is_ref, true); + } + } else if let syn::Type::Tuple(syn::TypeTuple { elems, .. }) = $item { + self.write_c_mangled_container_path_intern(w, elems.iter().collect(), + &format!("{}Tuple", elems.len()), is_ref, false, false, false); + } else { unimplemented!(); } + write!(w, ") -> {} =\n\t{}::CResultTempl::<", mangled_container, Self::container_templ_path()).unwrap(); + self.write_template_generics(w, &mut args.iter().map(|t| *t), is_ref, true); + writeln!(w, ">::{};\n", $call).unwrap(); + } } + } + match args[0] { + syn::Type::Tuple(t) if t.elems.is_empty() => write_fn!("ok"), + _ => write_alias!("ok", args[0]), + } + match args[1] { + syn::Type::Tuple(t) if t.elems.is_empty() => write_fn!("err"), + _ => write_alias!("err", args[1]), + } + } else if container_type.ends_with("Tuple") { + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_new(", mangled_container).unwrap(); + for (idx, gen) in args.iter().enumerate() { + write!(w, "{}{}: ", if idx != 0 { ", " } else { "" }, ('a' as u8 + idx as u8) as char).unwrap(); + self.write_c_type_intern(None, w, gen, false, false, false); + } + writeln!(w, ") -> {} {{", mangled_container).unwrap(); + writeln!(w, "\t{} {{", mangled_container).unwrap(); + for idx in 0..args.len() { + writeln!(w, "\t\t{}: Box::into_raw(Box::new({})),", ('a' as u8 + idx as u8) as char, ('a' as u8 + idx as u8) as char).unwrap(); + } + writeln!(w, "\t}}\n}}\n").unwrap(); + } else { + writeln!(w, "").unwrap(); + } + } + + fn write_template_generics<'b, W: std::io::Write>(&self, w: &mut W, args: &mut dyn Iterator, is_ref: bool, in_crate: bool) { + for (idx, t) in args.enumerate() { + if idx != 0 { + write!(w, ", ").unwrap(); + } + if let syn::Type::Tuple(tup) = t { + if tup.elems.is_empty() { + write!(w, "u8").unwrap(); + } else { + write!(w, "{}::C{}TupleTempl<", Self::container_templ_path(), tup.elems.len()).unwrap(); + self.write_template_generics(w, &mut tup.elems.iter(), is_ref, in_crate); + write!(w, ">").unwrap(); + } + } else if let syn::Type::Path(p_arg) = t { + let resolved_generic = self.resolve_path(&p_arg.path); + if self.is_primitive(&resolved_generic) { + write!(w, "{}", resolved_generic).unwrap(); + } else if let Some(c_type) = self.c_type_from_path(&resolved_generic, is_ref, false) { + if self.is_known_container(&resolved_generic, is_ref) { + write!(w, "{}::C{}Templ<", Self::container_templ_path(), single_ident_generic_path_to_ident(&p_arg.path).unwrap()).unwrap(); + assert_eq!(p_arg.path.segments.len(), 1); + if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments { + self.write_template_generics(w, &mut args.args.iter().map(|gen| + if let syn::GenericArgument::Type(t) = gen { t } else { unimplemented!() }), + is_ref, in_crate); + } else { unimplemented!(); } + write!(w, ">").unwrap(); + } else if resolved_generic == "Option" { + if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments { + self.write_template_generics(w, &mut args.args.iter().map(|gen| + if let syn::GenericArgument::Type(t) = gen { t } else { unimplemented!() }), + is_ref, in_crate); + } else { unimplemented!(); } + } else if in_crate { + write!(w, "{}", c_type).unwrap(); + } else { + self.write_rust_type(w, &t); + } + } else { + // If we just write out resolved_generic, it may mostly work, however for + // original types which are generic, we need the template args. We could + // figure them out and write them out, too, but its much easier to just + // reference the native{} type alias which exists at least for opaque types. + if in_crate { + write!(w, "crate::{}", resolved_generic).unwrap(); + } else { + let path_name: Vec<&str> = resolved_generic.rsplitn(2, "::").collect(); + if path_name.len() > 1 { + write!(w, "crate::{}::native{}", path_name[1], path_name[0]).unwrap(); + } else { + write!(w, "crate::native{}", path_name[0]).unwrap(); + } + } + } + } else if let syn::Type::Reference(r_arg) = t { + if let syn::Type::Path(p_arg) = &*r_arg.elem { + let resolved = self.resolve_path(&p_arg.path); + if single_ident_generic_path_to_ident(&p_arg.path).is_some() { + if self.crate_types.opaques.get(&resolved).is_some() { + write!(w, "crate::{}", resolved).unwrap(); + } else { unimplemented!(); } + } else { unimplemented!(); } + } else { unimplemented!(); } + } else if let syn::Type::Array(a_arg) = t { + if let syn::Type::Path(p_arg) = &*a_arg.elem { + let resolved = self.resolve_path(&p_arg.path); + assert!(self.is_primitive(&resolved)); + if let syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Int(len), .. }) = &a_arg.len { + write!(w, "{}", + self.c_type_from_path(&format!("[{}; {}]", resolved, len.base10_digits()), is_ref, false).unwrap()).unwrap(); + } + } + } + } + } + fn check_create_container(&mut self, mangled_container: String, container_type: &str, args: Vec<&syn::Type>, is_ref: bool) { + if !self.crate_types.templates_defined.get(&mangled_container).is_some() { + self.crate_types.templates_defined.insert(mangled_container.clone(), true); + let mut created_container: Vec = Vec::new(); + + write!(&mut created_container, "#[no_mangle]\npub type {} = ", mangled_container).unwrap(); + write!(&mut created_container, "{}::C{}Templ<", Self::container_templ_path(), container_type).unwrap(); + self.write_template_generics(&mut created_container, &mut args.iter().map(|t| *t), is_ref, true); + writeln!(&mut created_container, ">;").unwrap(); + + write!(&mut created_container, "#[no_mangle]\npub static {}_free: extern \"C\" fn({}) = ", mangled_container, mangled_container).unwrap(); + write!(&mut created_container, "{}::C{}Templ_free::<", Self::container_templ_path(), container_type).unwrap(); + self.write_template_generics(&mut created_container, &mut args.iter().map(|t| *t), is_ref, true); + writeln!(&mut created_container, ">;").unwrap(); + + self.write_template_constructor(&mut created_container, container_type, &mangled_container, &args, is_ref); + + self.crate_types.template_file.write(&created_container).unwrap(); + } + } + fn path_to_generic_args(path: &syn::Path) -> Vec<&syn::Type> { + if let syn::PathArguments::AngleBracketed(args) = &path.segments.iter().next().unwrap().arguments { + args.args.iter().map(|gen| if let syn::GenericArgument::Type(t) = gen { t } else { unimplemented!() }).collect() + } else { unimplemented!(); } + } + fn write_c_mangled_container_path_intern + (&mut self, w: &mut W, args: Vec<&syn::Type>, ident: &str, is_ref: bool, is_mut: bool, ptr_for_ref: bool, in_type: bool) -> bool { + let mut mangled_type: Vec = Vec::new(); + if !self.is_transparent_container(ident, is_ref) { + write!(w, "C{}_", ident).unwrap(); + write!(mangled_type, "C{}_", ident).unwrap(); + } else { assert_eq!(args.len(), 1); } + for arg in args.iter() { + macro_rules! write_path { + ($p_arg: expr, $extra_write: expr) => { + let subtype = self.resolve_path(&$p_arg.path); + if self.is_transparent_container(ident, is_ref) { + // We dont (yet) support primitives or containers inside transparent + // containers, so check for that first: + if self.is_primitive(&subtype) { return false; } + if self.is_known_container(&subtype, is_ref) { return false; } + if !in_type { + if self.c_type_has_inner_from_path(&subtype) { + if !self.write_c_path_intern(w, &$p_arg.path, is_ref, is_mut, ptr_for_ref) { return false; } + } else { + if !self.write_c_path_intern(w, &$p_arg.path, true, is_mut, true) { return false; } + } + } else { + if $p_arg.path.segments.len() == 1 { + write!(w, "{}", $p_arg.path.segments.iter().next().unwrap().ident).unwrap(); + } else { + return false; + } + } + } else if self.is_known_container(&subtype, is_ref) || self.is_transparent_container(&subtype, is_ref) { + if !self.write_c_mangled_container_path_intern(w, Self::path_to_generic_args(&$p_arg.path), + &subtype, is_ref, is_mut, ptr_for_ref, true) { + return false; + } + self.write_c_mangled_container_path_intern(&mut mangled_type, Self::path_to_generic_args(&$p_arg.path), + &subtype, is_ref, is_mut, ptr_for_ref, true); + if let Some(w2) = $extra_write as Option<&mut Vec> { + self.write_c_mangled_container_path_intern(w2, Self::path_to_generic_args(&$p_arg.path), + &subtype, is_ref, is_mut, ptr_for_ref, true); + } + } else if let Some(id) = single_ident_generic_path_to_ident(&$p_arg.path) { + write!(w, "{}", id).unwrap(); + write!(mangled_type, "{}", id).unwrap(); + if let Some(w2) = $extra_write as Option<&mut Vec> { + write!(w2, "{}", id).unwrap(); + } + } else { return false; } + } + } + if let syn::Type::Tuple(tuple) = arg { + if tuple.elems.len() == 0 { + write!(w, "None").unwrap(); + write!(mangled_type, "None").unwrap(); + } else { + let mut mangled_tuple_type: Vec = Vec::new(); + + // Figure out what the mangled type should look like. To disambiguate + // ((A, B), C) and (A, B, C) we prefix the generic args with a _ and suffix + // them with a Z. Ideally we wouldn't use Z, but not many special chars are + // available for use in type names. + write!(w, "C{}Tuple_", tuple.elems.len()).unwrap(); + write!(mangled_type, "C{}Tuple_", tuple.elems.len()).unwrap(); + write!(mangled_tuple_type, "C{}Tuple_", tuple.elems.len()).unwrap(); + for elem in tuple.elems.iter() { + if let syn::Type::Path(p) = elem { + write_path!(p, Some(&mut mangled_tuple_type)); + } else { return false; } + } + write!(w, "Z").unwrap(); + write!(mangled_type, "Z").unwrap(); + write!(mangled_tuple_type, "Z").unwrap(); + self.check_create_container(String::from_utf8(mangled_tuple_type).unwrap(), + &format!("{}Tuple", tuple.elems.len()), tuple.elems.iter().collect(), is_ref); + } + } else if let syn::Type::Path(p_arg) = arg { + write_path!(p_arg, None); + } else if let syn::Type::Reference(refty) = arg { + if args.len() != 1 { return false; } + if let syn::Type::Path(p_arg) = &*refty.elem { + write_path!(p_arg, None); + } else if let syn::Type::Slice(_) = &*refty.elem { + // write_c_type will actually do exactly what we want here, we just need to + // make it a pointer so that its an option. Note that we cannot always convert + // the Vec-as-slice (ie non-ref types) containers, so sometimes need to be able + // to edit it, hence we use *mut here instead of *const. + write!(w, "*mut ").unwrap(); + self.write_c_type(w, arg, None, true); + } else { return false; } + } else if let syn::Type::Array(a) = arg { + if let syn::Type::Path(p_arg) = &*a.elem { + let resolved = self.resolve_path(&p_arg.path); + if !self.is_primitive(&resolved) { return false; } + if let syn::Expr::Lit(syn::ExprLit { lit: syn::Lit::Int(len), .. }) = &a.len { + if self.c_type_from_path(&format!("[{}; {}]", resolved, len.base10_digits()), is_ref, ptr_for_ref).is_none() { return false; } + write!(w, "_{}{}", resolved, len.base10_digits()).unwrap(); + write!(mangled_type, "_{}{}", resolved, len.base10_digits()).unwrap(); + } else { return false; } + } else { return false; } + } else { return false; } + } + if self.is_transparent_container(ident, is_ref) { return true; } + // Push the "end of type" Z + write!(w, "Z").unwrap(); + write!(mangled_type, "Z").unwrap(); + + // Make sure the type is actually defined: + self.check_create_container(String::from_utf8(mangled_type).unwrap(), ident, args, is_ref); + true + } + fn write_c_mangled_container_path(&mut self, w: &mut W, args: Vec<&syn::Type>, ident: &str, is_ref: bool, is_mut: bool, ptr_for_ref: bool) -> bool { + if !self.is_transparent_container(ident, is_ref) { + write!(w, "{}::", Self::generated_container_path()).unwrap(); + } + self.write_c_mangled_container_path_intern(w, args, ident, is_ref, is_mut, ptr_for_ref, false) + } + + // ********************************** + // *** C Type Equivalent Printing *** + // ********************************** + + fn write_c_path_intern(&self, w: &mut W, path: &syn::Path, is_ref: bool, is_mut: bool, ptr_for_ref: bool) -> bool { +//eprintln!("pcpi ({} {} {}): {:?}", is_ref, is_mut, ptr_for_ref, path); + let full_path = match self.maybe_resolve_path(&path) { + Some(path) => path, None => return false }; + if let Some(c_type) = self.c_type_from_path(&full_path, is_ref, ptr_for_ref) { + write!(w, "{}", c_type).unwrap(); + true + } else if self.crate_types.traits.get(&full_path).is_some() { + if is_ref && ptr_for_ref { + write!(w, "*{} crate::{}", if is_mut { "mut" } else { "const" }, full_path).unwrap(); + } else if is_ref { + write!(w, "&{}crate::{}", if is_mut { "mut " } else { "" }, full_path).unwrap(); + } else { + write!(w, "crate::{}", full_path).unwrap(); + } + true + } else if self.crate_types.opaques.get(&full_path).is_some() || self.crate_types.mirrored_enums.get(&full_path).is_some() { + if is_ref && ptr_for_ref { + // ptr_for_ref implies we're returning the object, which we can't really do for + // opaque or mirrored types without box'ing them, which is quite a waste, so return + // the actual object itself (for opaque types we'll set the pointer to the actual + // type and note that its a reference). + write!(w, "crate::{}", full_path).unwrap(); + } else if is_ref { + write!(w, "&{}crate::{}", if is_mut { "mut " } else { "" }, full_path).unwrap(); + } else { + write!(w, "crate::{}", full_path).unwrap(); + } + true + } else { + false + } + } + fn write_c_type_intern(&mut self, generics: Option<&GenericTypes>, w: &mut W, t: &syn::Type, is_ref: bool, is_mut: bool, ptr_for_ref: bool) -> bool { + match t { + syn::Type::Path(p) => { + if p.qself.is_some() || p.path.leading_colon.is_some() { + return false; + } + if let Some(gen_types) = generics { + if let Some(resolved) = gen_types.maybe_resolve_path(&p.path) { + if self.is_known_container(&resolved.0, is_ref) { return false; } + if self.is_transparent_container(&resolved.0, is_ref) { return false; } + return self.write_c_path_intern(w, &resolved.1, is_ref, is_mut, ptr_for_ref); + } + } + if let Some(full_path) = self.maybe_resolve_path(&p.path) { + if self.is_known_container(&full_path, is_ref) || self.is_transparent_container(&full_path, is_ref) { + return self.write_c_mangled_container_path(w, Self::path_to_generic_args(&p.path), &full_path, is_ref, is_mut, ptr_for_ref); + } + } + if p.path.leading_colon.is_some() { return false; } + self.write_c_path_intern(w, &p.path, is_ref, is_mut, ptr_for_ref) + }, + syn::Type::Reference(r) => { + if let Some(lft) = &r.lifetime { + if format!("{}", lft.ident) != "static" { return false; } + } + self.write_c_type_intern(generics, w, &*r.elem, true, r.mutability.is_some(), ptr_for_ref) + }, + syn::Type::Array(a) => { + if is_ref && is_mut { + write!(w, "*mut [").unwrap(); + if !self.write_c_type_intern(generics, w, &a.elem, false, false, ptr_for_ref) { return false; } + } else if is_ref { + write!(w, "*const [").unwrap(); + if !self.write_c_type_intern(generics, w, &a.elem, false, false, ptr_for_ref) { return false; } + } else { + let mut typecheck = Vec::new(); + if !self.write_c_type_intern(generics, &mut typecheck, &a.elem, false, false, ptr_for_ref) { return false; } + if typecheck[..] != ['u' as u8, '8' as u8] { return false; } + } + if let syn::Expr::Lit(l) = &a.len { + if let syn::Lit::Int(i) = &l.lit { + if !is_ref { + if let Some(ty) = self.c_type_from_path(&format!("[u8; {}]", i.base10_digits()), false, ptr_for_ref) { + write!(w, "{}", ty).unwrap(); + true + } else { false } + } else { + write!(w, "; {}]", i).unwrap(); + true + } + } else { false } + } else { false } + } + syn::Type::Slice(s) => { + if !is_ref || is_mut { return false; } + if let syn::Type::Path(p) = &*s.elem { + let resolved = self.resolve_path(&p.path); + if self.is_primitive(&resolved) { + write!(w, "{}::{}slice", Self::container_templ_path(), resolved).unwrap(); + true + } else { false } + } else if let syn::Type::Reference(r) = &*s.elem { + if let syn::Type::Path(p) = &*r.elem { + // Slices with "real types" inside are mapped as the equivalent non-ref Vec + let resolved = self.resolve_path(&p.path); + let mangled_container = if let Some(ident) = self.crate_types.opaques.get(&resolved) { + format!("CVec_{}Z", ident) + } else if let Some(en) = self.crate_types.mirrored_enums.get(&resolved) { + format!("CVec_{}Z", en.ident) + } else if let Some(id) = p.path.get_ident() { + format!("CVec_{}Z", id) + } else { return false; }; + write!(w, "{}::{}", Self::generated_container_path(), mangled_container).unwrap(); + self.check_create_container(mangled_container, "Vec", vec![&*r.elem], false); + true + } else { false } + } else { false } + }, + syn::Type::Tuple(t) => { + if t.elems.len() == 0 { + true + } else { + self.write_c_mangled_container_path(w, t.elems.iter().collect(), + &format!("{}Tuple", t.elems.len()), is_ref, is_mut, ptr_for_ref) + } + }, + _ => false, + } + } + pub fn write_c_type(&mut self, w: &mut W, t: &syn::Type, generics: Option<&GenericTypes>, ptr_for_ref: bool) { + assert!(self.write_c_type_intern(generics, w, t, false, false, ptr_for_ref)); + } + pub fn understood_c_path(&mut self, p: &syn::Path) -> bool { + if p.leading_colon.is_some() { return false; } + self.write_c_path_intern(&mut std::io::sink(), p, false, false, false) + } + pub fn understood_c_type(&mut self, t: &syn::Type, generics: Option<&GenericTypes>) -> bool { + self.write_c_type_intern(generics, &mut std::io::sink(), t, false, false, false) + } +}