--- /dev/null
+//! 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: std::io::Write>(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: std::io::Write>(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<MappedTrait> 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<extern \"C\" fn(&{})>,", 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<extern \"C\" fn (this_arg: *const c_void) -> *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<extern \"C\" fn(this_arg: *mut c_void)>,").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<H: std::hash::Hasher>(&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<lightning::util::events::MessageSendEvent> {{").unwrap();
+ writeln!(w, "\t\t<crate::{} as lightning::{}>::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: std::io::Write>(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: std::io::Write>(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<Item = &'a syn::Item>> {
+ in_dir: &'a str,
+ path: &'a str,
+ module: &'a str,
+ item_iter: I,
+}
+impl<'a, I: Iterator<Item = &'a syn::Item>> Iterator for FileIter<'a, I> {
+ type Item = (String, String, &'a syn::ItemMod);
+ fn next(&mut self) -> std::option::Option<<Self as std::iter::Iterator>::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<Item = (String, String, &'a syn::ItemMod)> + '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<String, syn::File>,
+}
+
+/// 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<String> = 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 <string.h>\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();
+}
projects / rust-lightning / blobdiff