1 //! Converts a rust crate into a rust crate containing a number of C-exported wrapper functions and
2 //! classes (which is exportable using cbindgen).
3 //! In general, supports convering:
4 //! * structs as a pointer to the underlying type (either owned or not owned),
5 //! * traits as a void-ptr plus a jump table,
6 //! * enums as an equivalent enum with all the inner fields mapped to the mapped types,
7 //! * certain containers (tuples, slices, Vecs, Options, and Results currently) to a concrete
8 //! version of a defined container template.
10 //! It also generates relevant memory-management functions and free-standing functions with
11 //! parameters mapped.
13 use std::collections::{HashMap, hash_map, HashSet};
16 use std::io::{Read, Write};
19 use proc_macro2::{TokenTree, TokenStream, Span};
26 // *************************************
27 // *** Manually-expanded conversions ***
28 // *************************************
30 /// Because we don't expand macros, any code that we need to generated based on their contents has
31 /// to be completely manual. In this case its all just serialization, so its not too hard.
32 fn convert_macro<W: std::io::Write>(w: &mut W, macro_path: &syn::Path, stream: &TokenStream, types: &TypeResolver) {
33 assert_eq!(macro_path.segments.len(), 1);
34 match &format!("{}", macro_path.segments.iter().next().unwrap().ident) as &str {
35 "impl_writeable" | "impl_writeable_len_match" => {
36 let struct_for = if let TokenTree::Ident(i) = stream.clone().into_iter().next().unwrap() { i } else { unimplemented!(); };
37 if let Some(s) = types.maybe_resolve_ident(&struct_for) {
38 if !types.crate_types.opaques.get(&s).is_some() { return; }
39 writeln!(w, "#[no_mangle]").unwrap();
40 writeln!(w, "/// Serialize the {} into a byte array which can be read by {}_read", struct_for, struct_for).unwrap();
41 writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", struct_for, struct_for).unwrap();
42 writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap();
43 writeln!(w, "}}").unwrap();
44 writeln!(w, "#[no_mangle]").unwrap();
45 writeln!(w, "pub(crate) extern \"C\" fn {}_write_void(obj: *const c_void) -> crate::c_types::derived::CVec_u8Z {{", struct_for).unwrap();
46 writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &*(obj as *const native{}) }})", struct_for).unwrap();
47 writeln!(w, "}}").unwrap();
48 writeln!(w, "#[no_mangle]").unwrap();
49 writeln!(w, "/// Read a {} from a byte array, created by {}_write", struct_for, struct_for).unwrap();
50 writeln!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice) -> {} {{", struct_for, struct_for).unwrap();
51 writeln!(w, "\tif let Ok(res) = crate::c_types::deserialize_obj(ser) {{").unwrap();
52 writeln!(w, "\t\t{} {{ inner: Box::into_raw(Box::new(res)), is_owned: true }}", struct_for).unwrap();
53 writeln!(w, "\t}} else {{").unwrap();
54 writeln!(w, "\t\t{} {{ inner: std::ptr::null_mut(), is_owned: true }}", struct_for).unwrap();
55 writeln!(w, "\t}}\n}}").unwrap();
62 /// Convert "impl trait_path for for_ty { .. }" for manually-mapped types (ie (de)serialization)
63 fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path, for_ty: &syn::Type, types: &mut TypeResolver, generics: &GenericTypes) {
64 if let Some(t) = types.maybe_resolve_path(&trait_path, Some(generics)) {
67 let mut has_inner = false;
68 if let syn::Type::Path(ref p) = for_ty {
69 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
70 for_obj = format!("{}", ident);
71 full_obj_path = for_obj.clone();
72 has_inner = types.c_type_has_inner_from_path(&types.resolve_path(&p.path, Some(generics)));
75 // We assume that anything that isn't a Path is somehow a generic that ends up in our
76 // derived-types module.
77 let mut for_obj_vec = Vec::new();
78 types.write_c_type(&mut for_obj_vec, for_ty, Some(generics), false);
79 full_obj_path = String::from_utf8(for_obj_vec).unwrap();
80 assert!(full_obj_path.starts_with(TypeResolver::generated_container_path()));
81 for_obj = full_obj_path[TypeResolver::generated_container_path().len() + 2..].into();
85 "util::ser::Writeable" => {
86 writeln!(w, "#[no_mangle]").unwrap();
87 writeln!(w, "/// Serialize the {} object into a byte array which can be read by {}_read", for_obj, for_obj).unwrap();
88 writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, full_obj_path).unwrap();
90 let ref_type = syn::Type::Reference(syn::TypeReference {
91 and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None,
92 elem: Box::new(for_ty.clone()) });
93 assert!(!types.write_from_c_conversion_new_var(w, &syn::Ident::new("obj", Span::call_site()), &ref_type, Some(generics)));
95 write!(w, "\tcrate::c_types::serialize_obj(").unwrap();
96 types.write_from_c_conversion_prefix(w, &ref_type, Some(generics));
97 write!(w, "unsafe {{ &*obj }}").unwrap();
98 types.write_from_c_conversion_suffix(w, &ref_type, Some(generics));
99 writeln!(w, ")").unwrap();
101 writeln!(w, "}}").unwrap();
103 writeln!(w, "#[no_mangle]").unwrap();
104 writeln!(w, "pub(crate) extern \"C\" fn {}_write_void(obj: *const c_void) -> crate::c_types::derived::CVec_u8Z {{", for_obj).unwrap();
105 writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &*(obj as *const native{}) }})", for_obj).unwrap();
106 writeln!(w, "}}").unwrap();
109 "util::ser::Readable"|"util::ser::ReadableArgs" => {
110 // Create the Result<Object, DecodeError> syn::Type
111 let mut err_segs = syn::punctuated::Punctuated::new();
112 err_segs.push(syn::PathSegment { ident: syn::Ident::new("ln", Span::call_site()), arguments: syn::PathArguments::None });
113 err_segs.push(syn::PathSegment { ident: syn::Ident::new("msgs", Span::call_site()), arguments: syn::PathArguments::None });
114 err_segs.push(syn::PathSegment { ident: syn::Ident::new("DecodeError", Span::call_site()), arguments: syn::PathArguments::None });
115 let mut args = syn::punctuated::Punctuated::new();
116 args.push(syn::GenericArgument::Type(for_ty.clone()));
117 args.push(syn::GenericArgument::Type(syn::Type::Path(syn::TypePath {
118 qself: None, path: syn::Path {
119 leading_colon: Some(syn::Token![::](Span::call_site())), segments: err_segs,
122 let mut res_segs = syn::punctuated::Punctuated::new();
123 res_segs.push(syn::PathSegment {
124 ident: syn::Ident::new("Result", Span::call_site()),
125 arguments: syn::PathArguments::AngleBracketed(syn::AngleBracketedGenericArguments {
126 colon2_token: None, lt_token: syn::Token![<](Span::call_site()), args, gt_token: syn::Token![>](Span::call_site()),
129 let res_ty = syn::Type::Path(syn::TypePath { qself: None, path: syn::Path {
130 leading_colon: None, segments: res_segs } });
132 writeln!(w, "#[no_mangle]").unwrap();
133 writeln!(w, "/// Read a {} from a byte array, created by {}_write", for_obj, for_obj).unwrap();
134 write!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice", for_obj).unwrap();
136 let mut arg_conv = Vec::new();
137 if t == "util::ser::ReadableArgs" {
138 write!(w, ", arg: ").unwrap();
139 assert!(trait_path.leading_colon.is_none());
140 let args_seg = trait_path.segments.iter().last().unwrap();
141 assert_eq!(format!("{}", args_seg.ident), "ReadableArgs");
142 if let syn::PathArguments::AngleBracketed(args) = &args_seg.arguments {
143 assert_eq!(args.args.len(), 1);
144 if let syn::GenericArgument::Type(args_ty) = args.args.iter().next().unwrap() {
145 types.write_c_type(w, args_ty, Some(generics), false);
147 assert!(!types.write_from_c_conversion_new_var(&mut arg_conv, &syn::Ident::new("arg", Span::call_site()), &args_ty, Some(generics)));
149 write!(&mut arg_conv, "\tlet arg_conv = ").unwrap();
150 types.write_from_c_conversion_prefix(&mut arg_conv, &args_ty, Some(generics));
151 write!(&mut arg_conv, "arg").unwrap();
152 types.write_from_c_conversion_suffix(&mut arg_conv, &args_ty, Some(generics));
153 } else { unreachable!(); }
154 } else { unreachable!(); }
156 write!(w, ") -> ").unwrap();
157 types.write_c_type(w, &res_ty, Some(generics), false);
158 writeln!(w, " {{").unwrap();
160 if t == "util::ser::ReadableArgs" {
161 w.write(&arg_conv).unwrap();
162 write!(w, ";\n\tlet res: ").unwrap();
163 // At least in one case we need type annotations here, so provide them.
164 types.write_rust_type(w, Some(generics), &res_ty);
165 writeln!(w, " = crate::c_types::deserialize_obj_arg(ser, arg_conv);").unwrap();
167 writeln!(w, "\tlet res = crate::c_types::deserialize_obj(ser);").unwrap();
169 write!(w, "\t").unwrap();
170 if types.write_to_c_conversion_new_var(w, &syn::Ident::new("res", Span::call_site()), &res_ty, Some(generics), false) {
171 write!(w, "\n\t").unwrap();
173 types.write_to_c_conversion_inline_prefix(w, &res_ty, Some(generics), false);
174 write!(w, "res").unwrap();
175 types.write_to_c_conversion_inline_suffix(w, &res_ty, Some(generics), false);
176 writeln!(w, "\n}}").unwrap();
183 /// Convert "TraitA : TraitB" to a single function name and return type.
185 /// This is (obviously) somewhat over-specialized and only useful for TraitB's that only require a
186 /// single function (eg for serialization).
187 fn convert_trait_impl_field(trait_path: &str) -> (&'static str, String, &'static str) {
189 "util::ser::Writeable" => ("Serialize the object into a byte array", "write".to_owned(), "crate::c_types::derived::CVec_u8Z"),
190 _ => unimplemented!(),
194 /// Companion to convert_trait_impl_field, write an assignment for the function defined by it for
195 /// `for_obj` which implements the the trait at `trait_path`.
196 fn write_trait_impl_field_assign<W: std::io::Write>(w: &mut W, trait_path: &str, for_obj: &syn::Ident) {
198 "util::ser::Writeable" => {
199 writeln!(w, "\t\twrite: {}_write_void,", for_obj).unwrap();
201 _ => unimplemented!(),
205 /// Write out the impl block for a defined trait struct which has a supertrait
206 fn do_write_impl_trait<W: std::io::Write>(w: &mut W, trait_path: &str, trait_name: &syn::Ident, for_obj: &str) {
208 "util::events::MessageSendEventsProvider" => {
209 writeln!(w, "impl lightning::{} for {} {{", trait_path, for_obj).unwrap();
210 writeln!(w, "\tfn get_and_clear_pending_msg_events(&self) -> Vec<lightning::util::events::MessageSendEvent> {{").unwrap();
211 writeln!(w, "\t\t<crate::{} as lightning::{}>::get_and_clear_pending_msg_events(&self.{})", trait_path, trait_path, trait_name).unwrap();
212 writeln!(w, "\t}}\n}}").unwrap();
214 "util::ser::Writeable" => {
215 writeln!(w, "impl lightning::{} for {} {{", trait_path, for_obj).unwrap();
216 writeln!(w, "\tfn write<W: lightning::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {{").unwrap();
217 writeln!(w, "\t\tlet vec = (self.write)(self.this_arg);").unwrap();
218 writeln!(w, "\t\tw.write_all(vec.as_slice())").unwrap();
219 writeln!(w, "\t}}\n}}").unwrap();
225 // *******************************
226 // *** Per-Type Printing Logic ***
227 // *******************************
229 macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $pat: pat => $e: expr),*) ) => { {
230 if $t.colon_token.is_some() {
231 for st in $t.supertraits.iter() {
233 syn::TypeParamBound::Trait(supertrait) => {
234 if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() {
237 // First try to resolve path to find in-crate traits, but if that doesn't work
238 // assume its a prelude trait (eg Clone, etc) and just use the single ident.
239 let types_opt: Option<&TypeResolver> = $types;
240 if let Some(types) = types_opt {
241 if let Some(path) = types.maybe_resolve_path(&supertrait.path, None) {
242 match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
248 if let Some(ident) = supertrait.path.get_ident() {
249 match (&format!("{}", ident) as &str, &ident) {
252 } else if types_opt.is_some() {
253 panic!("Supertrait unresolvable and not single-ident");
256 syn::TypeParamBound::Lifetime(_) => unimplemented!(),
262 /// Prints a C-mapped trait object containing a void pointer and a jump table for each function in
263 /// the original trait.
264 /// Implements the native Rust trait and relevant parent traits for the new C-mapped trait.
266 /// Finally, implements Deref<MappedTrait> for MappedTrait which allows its use in types which need
267 /// a concrete Deref to the Rust trait.
268 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) {
269 let trait_name = format!("{}", t.ident);
270 match export_status(&t.attrs) {
271 ExportStatus::Export => {},
272 ExportStatus::NoExport|ExportStatus::TestOnly => return,
274 writeln_docs(w, &t.attrs, "");
276 let mut gen_types = GenericTypes::new();
277 assert!(gen_types.learn_generics(&t.generics, types));
278 gen_types.learn_associated_types(&t, types);
280 writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap();
281 writeln!(w, "\t/// An opaque pointer which is passed to your function implementations as an argument.").unwrap();
282 writeln!(w, "\t/// This has no meaning in the LDK, and can be NULL or any other value.").unwrap();
283 writeln!(w, "\tpub this_arg: *mut c_void,").unwrap();
284 let mut generated_fields = Vec::new(); // Every field's name except this_arg, used in Clone generation
285 for item in t.items.iter() {
287 &syn::TraitItem::Method(ref m) => {
288 match export_status(&m.attrs) {
289 ExportStatus::NoExport => {
290 // NoExport in this context means we'll hit an unimplemented!() at runtime,
294 ExportStatus::Export => {},
295 ExportStatus::TestOnly => continue,
297 if m.default.is_some() { unimplemented!(); }
299 gen_types.push_ctx();
300 assert!(gen_types.learn_generics(&m.sig.generics, types));
302 writeln_docs(w, &m.attrs, "\t");
304 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
305 if let syn::Type::Reference(r) = &**rtype {
306 // We have to do quite a dance for trait functions which return references
307 // - they ultimately require us to have a native Rust object stored inside
308 // our concrete trait to return a reference to. However, users may wish to
309 // update the value to be returned each time the function is called (or, to
310 // make C copies of Rust impls equivalent, we have to be able to).
312 // Thus, we store a copy of the C-mapped type (which is just a pointer to
313 // the Rust type and a flag to indicate whether deallocation needs to
314 // happen) as well as provide an Option<>al function pointer which is
315 // called when the trait method is called which allows updating on the fly.
316 write!(w, "\tpub {}: ", m.sig.ident).unwrap();
317 generated_fields.push(format!("{}", m.sig.ident));
318 types.write_c_type(w, &*r.elem, Some(&gen_types), false);
319 writeln!(w, ",").unwrap();
320 writeln!(w, "\t/// Fill in the {} field as a reference to it will be given to Rust after this returns", m.sig.ident).unwrap();
321 writeln!(w, "\t/// Note that this takes a pointer to this object, not the this_ptr like other methods do").unwrap();
322 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();
323 writeln!(w, "\tpub set_{}: Option<extern \"C\" fn(&{})>,", m.sig.ident, trait_name).unwrap();
324 generated_fields.push(format!("set_{}", m.sig.ident));
325 // Note that cbindgen will now generate
326 // typedef struct Thing {..., set_thing: (const Thing*), ...} Thing;
327 // which does not compile since Thing is not defined before it is used.
328 writeln!(extra_headers, "struct LDK{};", trait_name).unwrap();
329 writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap();
333 // Sadly, this currently doesn't do what we want, but it should be easy to get
334 // cbindgen to support it. See https://github.com/eqrion/cbindgen/issues/531
335 writeln!(w, "\t#[must_use]").unwrap();
338 write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap();
339 generated_fields.push(format!("{}", m.sig.ident));
340 write_method_params(w, &m.sig, "c_void", types, Some(&gen_types), true, false);
341 writeln!(w, ",").unwrap();
345 &syn::TraitItem::Type(_) => {},
346 _ => unimplemented!(),
349 // Add functions which may be required for supertrait implementations.
350 walk_supertraits!(t, Some(&types), (
352 writeln!(w, "\t/// Creates a copy of the object pointed to by this_arg, for a copy of this {}.", trait_name).unwrap();
353 writeln!(w, "\t/// Note that the ultimate copy of the {} will have all function pointers the same as the original.", trait_name).unwrap();
354 writeln!(w, "\t/// May be NULL if no action needs to be taken, the this_arg pointer will be copied into the new {}.", trait_name).unwrap();
355 writeln!(w, "\tpub clone: Option<extern \"C\" fn (this_arg: *const c_void) -> *mut c_void>,").unwrap();
356 generated_fields.push("clone".to_owned());
358 ("std::cmp::Eq", _) => {
359 writeln!(w, "\t/// Checks if two objects are equal given this object's this_arg pointer and another object.").unwrap();
360 writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap();
361 writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap();
362 generated_fields.push("eq".to_owned());
364 ("std::hash::Hash", _) => {
365 writeln!(w, "\t/// Calculate a succinct non-cryptographic hash for an object given its this_arg pointer.").unwrap();
366 writeln!(w, "\t/// This is used, for example, for inclusion of this object in a hash map.").unwrap();
367 writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap();
368 generated_fields.push("hash".to_owned());
370 ("Send", _) => {}, ("Sync", _) => {},
372 generated_fields.push(if types.crate_types.traits.get(s).is_none() {
373 let (docs, name, ret) = convert_trait_impl_field(s);
374 writeln!(w, "\t/// {}", docs).unwrap();
375 writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap();
378 // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
379 writeln!(w, "/// Implementation of {} for this object.", i).unwrap();
380 writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
385 writeln!(w, "/// Frees any resources associated with this object given its this_arg pointer.").unwrap();
386 writeln!(w, "/// Does not need to free the outer struct containing function pointers and may be NULL is no resources need to be freed.").unwrap();
387 writeln!(w, "\tpub free: Option<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
388 generated_fields.push("free".to_owned());
389 writeln!(w, "}}").unwrap();
390 // Implement supertraits for the C-mapped struct.
391 walk_supertraits!(t, Some(&types), (
392 ("Send", _) => writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(),
393 ("Sync", _) => writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(),
394 ("std::cmp::Eq", _) => {
395 writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap();
396 writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap();
397 writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o) }}\n}}").unwrap();
399 ("std::hash::Hash", _) => {
400 writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap();
401 writeln!(w, "\tfn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap();
404 writeln!(w, "#[no_mangle]").unwrap();
405 writeln!(w, "/// Creates a copy of a {}", trait_name).unwrap();
406 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
407 writeln!(w, "\t{} {{", trait_name).unwrap();
408 writeln!(w, "\t\tthis_arg: if let Some(f) = orig.clone {{ (f)(orig.this_arg) }} else {{ orig.this_arg }},").unwrap();
409 for field in generated_fields.iter() {
410 writeln!(w, "\t\t{}: orig.{}.clone(),", field, field).unwrap();
412 writeln!(w, "\t}}\n}}").unwrap();
413 writeln!(w, "impl Clone for {} {{", trait_name).unwrap();
414 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
415 writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap();
416 writeln!(w, "\t}}\n}}").unwrap();
419 do_write_impl_trait(w, s, i, &trait_name);
423 // Finally, implement the original Rust trait for the newly created mapped trait.
424 writeln!(w, "\nuse {}::{}::{} as rust{};", types.orig_crate, types.module_path, t.ident, trait_name).unwrap();
425 write!(w, "impl rust{}", t.ident).unwrap();
426 maybe_write_generics(w, &t.generics, types, false);
427 writeln!(w, " for {} {{", trait_name).unwrap();
428 for item in t.items.iter() {
430 syn::TraitItem::Method(m) => {
431 if let ExportStatus::TestOnly = export_status(&m.attrs) { continue; }
432 if m.default.is_some() { unimplemented!(); }
433 if m.sig.constness.is_some() || m.sig.asyncness.is_some() || m.sig.unsafety.is_some() ||
434 m.sig.abi.is_some() || m.sig.variadic.is_some() {
437 gen_types.push_ctx();
438 assert!(gen_types.learn_generics(&m.sig.generics, types));
439 write!(w, "\tfn {}", m.sig.ident).unwrap();
440 types.write_rust_generic_param(w, Some(&gen_types), m.sig.generics.params.iter());
441 write!(w, "(").unwrap();
442 for inp in m.sig.inputs.iter() {
444 syn::FnArg::Receiver(recv) => {
445 if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
446 write!(w, "&").unwrap();
447 if let Some(lft) = &recv.reference.as_ref().unwrap().1 {
448 write!(w, "'{} ", lft.ident).unwrap();
450 if recv.mutability.is_some() {
451 write!(w, "mut self").unwrap();
453 write!(w, "self").unwrap();
456 syn::FnArg::Typed(arg) => {
457 if !arg.attrs.is_empty() { unimplemented!(); }
459 syn::Pat::Ident(ident) => {
460 if !ident.attrs.is_empty() || ident.by_ref.is_some() ||
461 ident.mutability.is_some() || ident.subpat.is_some() {
464 write!(w, ", {}{}: ", if types.skip_arg(&*arg.ty, Some(&gen_types)) { "_" } else { "" }, ident.ident).unwrap();
466 _ => unimplemented!(),
468 types.write_rust_type(w, Some(&gen_types), &*arg.ty);
472 write!(w, ")").unwrap();
473 match &m.sig.output {
474 syn::ReturnType::Type(_, rtype) => {
475 write!(w, " -> ").unwrap();
476 types.write_rust_type(w, Some(&gen_types), &*rtype)
480 write!(w, " {{\n\t\t").unwrap();
481 match export_status(&m.attrs) {
482 ExportStatus::NoExport => {
487 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
488 if let syn::Type::Reference(r) = &**rtype {
489 assert_eq!(m.sig.inputs.len(), 1); // Must only take self!
490 writeln!(w, "if let Some(f) = self.set_{} {{", m.sig.ident).unwrap();
491 writeln!(w, "\t\t\t(f)(self);").unwrap();
492 write!(w, "\t\t}}\n\t\t").unwrap();
493 types.write_from_c_conversion_to_ref_prefix(w, &*r.elem, Some(&gen_types));
494 write!(w, "self.{}", m.sig.ident).unwrap();
495 types.write_from_c_conversion_to_ref_suffix(w, &*r.elem, Some(&gen_types));
496 writeln!(w, "\n\t}}").unwrap();
501 write_method_var_decl_body(w, &m.sig, "\t", types, Some(&gen_types), true);
502 write!(w, "(self.{})(", m.sig.ident).unwrap();
503 write_method_call_params(w, &m.sig, "\t", types, Some(&gen_types), "", true);
505 writeln!(w, "\n\t}}").unwrap();
508 &syn::TraitItem::Type(ref t) => {
509 if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); }
510 let mut bounds_iter = t.bounds.iter();
511 match bounds_iter.next().unwrap() {
512 syn::TypeParamBound::Trait(tr) => {
513 writeln!(w, "\ttype {} = crate::{};", t.ident, types.resolve_path(&tr.path, Some(&gen_types))).unwrap();
515 _ => unimplemented!(),
517 if bounds_iter.next().is_some() { unimplemented!(); }
519 _ => unimplemented!(),
522 writeln!(w, "}}\n").unwrap();
523 writeln!(w, "// We're essentially a pointer already, or at least a set of pointers, so allow us to be used").unwrap();
524 writeln!(w, "// directly as a Deref trait in higher-level structs:").unwrap();
525 writeln!(w, "impl std::ops::Deref for {} {{\n\ttype Target = Self;", trait_name).unwrap();
526 writeln!(w, "\tfn deref(&self) -> &Self {{\n\t\tself\n\t}}\n}}").unwrap();
528 writeln!(w, "/// Calls the free function if one is set").unwrap();
529 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", trait_name, trait_name).unwrap();
530 writeln!(w, "impl Drop for {} {{", trait_name).unwrap();
531 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
532 writeln!(w, "\t\tif let Some(f) = self.free {{").unwrap();
533 writeln!(w, "\t\t\tf(self.this_arg);").unwrap();
534 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
536 write_cpp_wrapper(cpp_headers, &trait_name, true);
539 /// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type
540 /// and a flag to indicate whether Drop'ing the mapped struct drops the underlying Rust type.
542 /// Also writes out a _free function and a C++ wrapper which handles calling _free.
543 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) {
544 // If we directly read the original type by its original name, cbindgen hits
545 // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary
546 // name and then reference it by that name, which works around the issue.
547 write!(w, "\nuse {}::{}::{} as native{}Import;\ntype native{} = native{}Import", types.orig_crate, types.module_path, ident, ident, ident, ident).unwrap();
548 maybe_write_generics(w, &generics, &types, true);
549 writeln!(w, ";\n").unwrap();
550 writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap();
551 writeln_docs(w, &attrs, "");
552 writeln!(w, "#[must_use]\n#[repr(C)]\npub struct {} {{", struct_name).unwrap();
553 writeln!(w, "\t/// A pointer to the opaque Rust object.\n").unwrap();
554 writeln!(w, "\t/// Nearly everywhere, inner must be non-null, however in places where").unwrap();
555 writeln!(w, "\t/// the Rust equivalent takes an Option, it may be set to null to indicate None.").unwrap();
556 writeln!(w, "\tpub inner: *mut native{},", ident).unwrap();
557 writeln!(w, "\t/// Indicates that this is the only struct which contains the same pointer.\n").unwrap();
558 writeln!(w, "\t/// Rust functions which take ownership of an object provided via an argument require").unwrap();
559 writeln!(w, "\t/// this to be true and invalidate the object pointed to by inner.").unwrap();
560 writeln!(w, "\tpub is_owned: bool,").unwrap();
561 writeln!(w, "}}\n").unwrap();
562 writeln!(w, "impl Drop for {} {{\n\tfn drop(&mut self) {{", struct_name).unwrap();
563 writeln!(w, "\t\tif self.is_owned && !<*mut native{}>::is_null(self.inner) {{", ident).unwrap();
564 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(self.inner) }};\n\t\t}}\n\t}}\n}}").unwrap();
565 writeln!(w, "/// Frees any resources used by the {}, if is_owned is set and inner is non-NULL.", struct_name).unwrap();
566 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_obj: {}) {{ }}", struct_name, struct_name).unwrap();
567 writeln!(w, "#[allow(unused)]").unwrap();
568 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
569 writeln!(w, "extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
570 writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap();
571 writeln!(w, "#[allow(unused)]").unwrap();
572 writeln!(w, "/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap();
573 writeln!(w, "impl {} {{", struct_name).unwrap();
574 writeln!(w, "\tpub(crate) fn take_inner(mut self) -> *mut native{} {{", struct_name).unwrap();
575 writeln!(w, "\t\tassert!(self.is_owned);").unwrap();
576 writeln!(w, "\t\tlet ret = self.inner;").unwrap();
577 writeln!(w, "\t\tself.inner = std::ptr::null_mut();").unwrap();
578 writeln!(w, "\t\tret").unwrap();
579 writeln!(w, "\t}}\n}}").unwrap();
581 write_cpp_wrapper(cpp_headers, &format!("{}", ident), true);
584 /// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
585 /// the struct itself, and then writing getters and setters for public, understood-type fields and
586 /// a constructor if every field is public.
587 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) {
588 if export_status(&s.attrs) != ExportStatus::Export { return; }
590 let struct_name = &format!("{}", s.ident);
591 writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers);
593 if let syn::Fields::Named(fields) = &s.fields {
594 let mut gen_types = GenericTypes::new();
595 assert!(gen_types.learn_generics(&s.generics, types));
597 let mut all_fields_settable = true;
598 for field in fields.named.iter() {
599 if let syn::Visibility::Public(_) = field.vis {
600 let export = export_status(&field.attrs);
602 ExportStatus::Export => {},
603 ExportStatus::NoExport|ExportStatus::TestOnly => {
604 all_fields_settable = false;
609 if let Some(ident) = &field.ident {
610 let ref_type = syn::Type::Reference(syn::TypeReference {
611 and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None,
612 elem: Box::new(field.ty.clone()) });
613 if types.understood_c_type(&ref_type, Some(&gen_types)) {
614 writeln_docs(w, &field.attrs, "");
615 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, ident, struct_name).unwrap();
616 types.write_c_type(w, &ref_type, Some(&gen_types), true);
617 write!(w, " {{\n\tlet mut inner_val = &mut unsafe {{ &mut *this_ptr.inner }}.{};\n\t", ident).unwrap();
618 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);
619 if local_var { write!(w, "\n\t").unwrap(); }
620 types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true);
622 write!(w, "inner_val").unwrap();
624 write!(w, "(*inner_val)").unwrap();
626 types.write_to_c_conversion_inline_suffix(w, &ref_type, Some(&gen_types), true);
627 writeln!(w, "\n}}").unwrap();
630 if types.understood_c_type(&field.ty, Some(&gen_types)) {
631 writeln_docs(w, &field.attrs, "");
632 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, ident, struct_name).unwrap();
633 types.write_c_type(w, &field.ty, Some(&gen_types), false);
634 write!(w, ") {{\n\t").unwrap();
635 let local_var = types.write_from_c_conversion_new_var(w, &syn::Ident::new("val", Span::call_site()), &field.ty, Some(&gen_types));
636 if local_var { write!(w, "\n\t").unwrap(); }
637 write!(w, "unsafe {{ &mut *this_ptr.inner }}.{} = ", ident).unwrap();
638 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
639 write!(w, "val").unwrap();
640 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
641 writeln!(w, ";\n}}").unwrap();
642 } else { all_fields_settable = false; }
643 } else { all_fields_settable = false; }
644 } else { all_fields_settable = false; }
647 if all_fields_settable {
648 // Build a constructor!
649 writeln!(w, "/// Constructs a new {} given each field", struct_name).unwrap();
650 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_new(", struct_name).unwrap();
651 for (idx, field) in fields.named.iter().enumerate() {
652 if idx != 0 { write!(w, ", ").unwrap(); }
653 write!(w, "mut {}_arg: ", field.ident.as_ref().unwrap()).unwrap();
654 types.write_c_type(w, &field.ty, Some(&gen_types), false);
656 write!(w, ") -> {} {{\n\t", struct_name).unwrap();
657 for field in fields.named.iter() {
658 let field_name = format!("{}_arg", field.ident.as_ref().unwrap());
659 if types.write_from_c_conversion_new_var(w, &syn::Ident::new(&field_name, Span::call_site()), &field.ty, Some(&gen_types)) {
660 write!(w, "\n\t").unwrap();
663 writeln!(w, "{} {{ inner: Box::into_raw(Box::new(native{} {{", struct_name, s.ident).unwrap();
664 for field in fields.named.iter() {
665 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
666 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
667 write!(w, "{}_arg", field.ident.as_ref().unwrap()).unwrap();
668 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
669 writeln!(w, ",").unwrap();
671 writeln!(w, "\t}})), is_owned: true }}\n}}").unwrap();
676 /// Prints a relevant conversion for impl *
678 /// For simple impl Struct {}s, this just outputs the wrapper functions as Struct_fn_name() { .. }.
680 /// For impl Trait for Struct{}s, this non-exported generates wrapper functions as
681 /// Trait_Struct_fn_name and a Struct_as_Trait(&struct) -> Trait function which returns a populated
682 /// Trait struct containing a pointer to the passed struct's inner field and the wrapper functions.
684 /// A few non-crate Traits are hard-coded including Default.
685 fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) {
686 match export_status(&i.attrs) {
687 ExportStatus::Export => {},
688 ExportStatus::NoExport|ExportStatus::TestOnly => return,
691 if let syn::Type::Tuple(_) = &*i.self_ty {
692 if types.understood_c_type(&*i.self_ty, None) {
693 let mut gen_types = GenericTypes::new();
694 if !gen_types.learn_generics(&i.generics, types) {
695 eprintln!("Not implementing anything for `impl (..)` due to not understood generics");
699 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
700 if let Some(trait_path) = i.trait_.as_ref() {
701 if trait_path.0.is_some() { unimplemented!(); }
702 if types.understood_c_path(&trait_path.1) {
703 eprintln!("Not implementing anything for `impl Trait for (..)` - we only support manual defines");
706 // Just do a manual implementation:
707 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
710 eprintln!("Not implementing anything for plain `impl (..)` block - we only support `impl Trait for (..)` blocks");
716 if let &syn::Type::Path(ref p) = &*i.self_ty {
717 if p.qself.is_some() { unimplemented!(); }
718 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
719 if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) {
720 let mut gen_types = GenericTypes::new();
721 if !gen_types.learn_generics(&i.generics, types) {
722 eprintln!("Not implementing anything for impl {} due to not understood generics", ident);
726 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
727 if let Some(trait_path) = i.trait_.as_ref() {
728 if trait_path.0.is_some() { unimplemented!(); }
729 if types.understood_c_path(&trait_path.1) {
730 let full_trait_path = types.resolve_path(&trait_path.1, None);
731 let trait_obj = *types.crate_types.traits.get(&full_trait_path).unwrap();
732 // We learn the associated types maping from the original trait object.
733 // That's great, except that they are unresolved idents, so if we learn
734 // mappings from a trai defined in a different file, we may mis-resolve or
735 // fail to resolve the mapped types.
736 gen_types.learn_associated_types(trait_obj, types);
737 let mut impl_associated_types = HashMap::new();
738 for item in i.items.iter() {
740 syn::ImplItem::Type(t) => {
741 if let syn::Type::Path(p) = &t.ty {
742 if let Some(id) = single_ident_generic_path_to_ident(&p.path) {
743 impl_associated_types.insert(&t.ident, id);
751 let export = export_status(&trait_obj.attrs);
753 ExportStatus::Export => {},
754 ExportStatus::NoExport|ExportStatus::TestOnly => return,
757 // For cases where we have a concrete native object which implements a
758 // trait and need to return the C-mapped version of the trait, provide a
759 // From<> implementation which does all the work to ensure free is handled
760 // properly. This way we can call this method from deep in the
761 // type-conversion logic without actually knowing the concrete native type.
762 writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
763 writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();
764 writeln!(w, "\t\tlet mut rust_obj = {} {{ inner: Box::into_raw(Box::new(obj)), is_owned: true }};", ident).unwrap();
765 writeln!(w, "\t\tlet mut ret = {}_as_{}(&rust_obj);", ident, trait_obj.ident).unwrap();
766 writeln!(w, "\t\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").unwrap();
767 writeln!(w, "\t\trust_obj.inner = std::ptr::null_mut();").unwrap();
768 writeln!(w, "\t\tret.free = Some({}_free_void);", ident).unwrap();
769 writeln!(w, "\t\tret\n\t}}\n}}").unwrap();
771 writeln!(w, "/// Constructs a new {} which calls the relevant methods on this_arg.", trait_obj.ident).unwrap();
772 writeln!(w, "/// This copies the `inner` pointer in this_arg and thus the returned {} must be freed before this_arg is", trait_obj.ident).unwrap();
773 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: &{}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
774 writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
775 writeln!(w, "\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
776 writeln!(w, "\t\tfree: None,").unwrap();
778 macro_rules! write_meth {
779 ($m: expr, $trait: expr, $indent: expr) => {
780 let trait_method = $trait.items.iter().filter_map(|item| {
781 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
782 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
783 match export_status(&trait_method.attrs) {
784 ExportStatus::Export => {},
785 ExportStatus::NoExport => {
786 write!(w, "{}\t\t//XXX: Need to export {}\n", $indent, $m.sig.ident).unwrap();
789 ExportStatus::TestOnly => continue,
792 let mut printed = false;
793 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
794 if let syn::Type::Reference(r) = &**rtype {
795 write!(w, "\n\t\t{}{}: ", $indent, $m.sig.ident).unwrap();
796 types.write_empty_rust_val(Some(&gen_types), w, &*r.elem);
797 writeln!(w, ",\n{}\t\tset_{}: Some({}_{}_set_{}),", $indent, $m.sig.ident, ident, trait_obj.ident, $m.sig.ident).unwrap();
802 write!(w, "{}\t\t{}: {}_{}_{},\n", $indent, $m.sig.ident, ident, trait_obj.ident, $m.sig.ident).unwrap();
806 for item in trait_obj.items.iter() {
808 syn::TraitItem::Method(m) => {
809 write_meth!(m, trait_obj, "");
814 walk_supertraits!(trait_obj, Some(&types), (
816 writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap();
818 ("Sync", _) => {}, ("Send", _) => {},
819 ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
821 if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
822 writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();
823 writeln!(w, "\t\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
824 writeln!(w, "\t\t\tfree: None,").unwrap();
825 for item in supertrait_obj.items.iter() {
827 syn::TraitItem::Method(m) => {
828 write_meth!(m, supertrait_obj, "\t");
833 write!(w, "\t\t}},\n").unwrap();
835 write_trait_impl_field_assign(w, s, ident);
839 writeln!(w, "\t}}\n}}\n").unwrap();
841 macro_rules! impl_meth {
842 ($m: expr, $trait_path: expr, $trait: expr, $indent: expr) => {
843 let trait_method = $trait.items.iter().filter_map(|item| {
844 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
845 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
846 match export_status(&trait_method.attrs) {
847 ExportStatus::Export => {},
848 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
851 if let syn::ReturnType::Type(_, _) = &$m.sig.output {
852 writeln!(w, "#[must_use]").unwrap();
854 write!(w, "extern \"C\" fn {}_{}_{}(", ident, trait_obj.ident, $m.sig.ident).unwrap();
855 gen_types.push_ctx();
856 assert!(gen_types.learn_generics(&$m.sig.generics, types));
857 write_method_params(w, &$m.sig, "c_void", types, Some(&gen_types), true, true);
858 write!(w, " {{\n\t").unwrap();
859 write_method_var_decl_body(w, &$m.sig, "", types, Some(&gen_types), false);
860 let mut takes_self = false;
861 for inp in $m.sig.inputs.iter() {
862 if let syn::FnArg::Receiver(_) = inp {
867 let mut t_gen_args = String::new();
868 for (idx, _) in $trait.generics.params.iter().enumerate() {
869 if idx != 0 { t_gen_args += ", " };
873 write!(w, "<native{} as {}::{}<{}>>::{}(unsafe {{ &mut *(this_arg as *mut native{}) }}, ", ident, types.orig_crate, $trait_path, t_gen_args, $m.sig.ident, ident).unwrap();
875 write!(w, "<native{} as {}::{}<{}>>::{}(", ident, types.orig_crate, $trait_path, t_gen_args, $m.sig.ident).unwrap();
878 let mut real_type = "".to_string();
879 match &$m.sig.output {
880 syn::ReturnType::Type(_, rtype) => {
881 if let Some(mut remaining_path) = first_seg_self(&*rtype) {
882 if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
883 real_type = format!("{}", impl_associated_types.get(associated_seg).unwrap());
889 write_method_call_params(w, &$m.sig, "", types, Some(&gen_types), &real_type, false);
891 write!(w, "\n}}\n").unwrap();
892 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
893 if let syn::Type::Reference(r) = &**rtype {
894 assert_eq!($m.sig.inputs.len(), 1); // Must only take self
895 writeln!(w, "extern \"C\" fn {}_{}_set_{}(trait_self_arg: &{}) {{", ident, trait_obj.ident, $m.sig.ident, trait_obj.ident).unwrap();
896 writeln!(w, "\t// This is a bit race-y in the general case, but for our specific use-cases today, we're safe").unwrap();
897 writeln!(w, "\t// Specifically, we must ensure that the first time we're called it can never be in parallel").unwrap();
898 write!(w, "\tif ").unwrap();
899 types.write_empty_rust_val_check(Some(&gen_types), w, &*r.elem, &format!("trait_self_arg.{}", $m.sig.ident));
900 writeln!(w, " {{").unwrap();
901 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();
902 writeln!(w, "\t}}").unwrap();
903 writeln!(w, "}}").unwrap();
909 for item in i.items.iter() {
911 syn::ImplItem::Method(m) => {
912 impl_meth!(m, full_trait_path, trait_obj, "");
914 syn::ImplItem::Type(_) => {},
915 _ => unimplemented!(),
918 walk_supertraits!(trait_obj, Some(&types), (
920 if let Some(supertrait_obj) = types.crate_types.traits.get(s).cloned() {
921 for item in supertrait_obj.items.iter() {
923 syn::TraitItem::Method(m) => {
924 impl_meth!(m, s, supertrait_obj, "\t");
932 write!(w, "\n").unwrap();
933 } else if path_matches_nongeneric(&trait_path.1, &["From"]) {
934 } else if path_matches_nongeneric(&trait_path.1, &["Default"]) {
935 writeln!(w, "/// Creates a \"default\" {}. See struct and individual field documentaiton for details on which values are used.", ident).unwrap();
936 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_default() -> {} {{\n", ident, ident).unwrap();
937 write!(w, "\t{} {{ inner: Box::into_raw(Box::new(Default::default())), is_owned: true }}\n", ident).unwrap();
938 write!(w, "}}\n").unwrap();
939 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "PartialEq"]) {
940 } else if (path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) || path_matches_nongeneric(&trait_path.1, &["Clone"])) &&
941 types.c_type_has_inner_from_path(&resolved_path) {
942 writeln!(w, "impl Clone for {} {{", ident).unwrap();
943 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
944 writeln!(w, "\t\tSelf {{").unwrap();
945 writeln!(w, "\t\t\tinner: if <*mut native{}>::is_null(self.inner) {{ std::ptr::null_mut() }} else {{", ident).unwrap();
946 writeln!(w, "\t\t\t\tBox::into_raw(Box::new(unsafe {{ &*self.inner }}.clone())) }},").unwrap();
947 writeln!(w, "\t\t\tis_owned: true,").unwrap();
948 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
949 writeln!(w, "#[allow(unused)]").unwrap();
950 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
951 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", ident).unwrap();
952 writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", ident).unwrap();
953 writeln!(w, "}}").unwrap();
954 writeln!(w, "#[no_mangle]").unwrap();
955 writeln!(w, "/// Creates a copy of the {}", ident).unwrap();
956 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", ident, ident, ident).unwrap();
957 writeln!(w, "\torig.clone()").unwrap();
958 writeln!(w, "}}").unwrap();
960 //XXX: implement for other things like ToString
961 // If we have no generics, try a manual implementation:
962 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
965 let declared_type = (*types.get_declared_type(&ident).unwrap()).clone();
966 for item in i.items.iter() {
968 syn::ImplItem::Method(m) => {
969 if let syn::Visibility::Public(_) = m.vis {
970 match export_status(&m.attrs) {
971 ExportStatus::Export => {},
972 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
974 if m.defaultness.is_some() { unimplemented!(); }
975 writeln_docs(w, &m.attrs, "");
976 if let syn::ReturnType::Type(_, _) = &m.sig.output {
977 writeln!(w, "#[must_use]").unwrap();
979 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}(", ident, m.sig.ident).unwrap();
980 let ret_type = match &declared_type {
981 DeclType::MirroredEnum => format!("{}", ident),
982 DeclType::StructImported => format!("{}", ident),
983 _ => unimplemented!(),
985 gen_types.push_ctx();
986 assert!(gen_types.learn_generics(&m.sig.generics, types));
987 write_method_params(w, &m.sig, &ret_type, types, Some(&gen_types), false, true);
988 write!(w, " {{\n\t").unwrap();
989 write_method_var_decl_body(w, &m.sig, "", types, Some(&gen_types), false);
990 let mut takes_self = false;
991 let mut takes_mut_self = false;
992 for inp in m.sig.inputs.iter() {
993 if let syn::FnArg::Receiver(r) = inp {
995 if r.mutability.is_some() { takes_mut_self = true; }
999 write!(w, "unsafe {{ &mut (*(this_arg.inner as *mut native{})) }}.{}(", ident, m.sig.ident).unwrap();
1000 } else if takes_self {
1001 write!(w, "unsafe {{ &*this_arg.inner }}.{}(", m.sig.ident).unwrap();
1003 write!(w, "{}::{}::{}(", types.orig_crate, resolved_path, m.sig.ident).unwrap();
1005 write_method_call_params(w, &m.sig, "", types, Some(&gen_types), &ret_type, false);
1006 gen_types.pop_ctx();
1007 writeln!(w, "\n}}\n").unwrap();
1014 } else if let Some(resolved_path) = types.maybe_resolve_ident(&ident) {
1015 if let Some(aliases) = types.crate_types.reverse_alias_map.get(&resolved_path).cloned() {
1016 'alias_impls: for (alias, arguments) in aliases {
1017 let alias_resolved = types.resolve_path(&alias, None);
1018 for (idx, gen) in i.generics.params.iter().enumerate() {
1020 syn::GenericParam::Type(type_param) => {
1021 'bounds_check: for bound in type_param.bounds.iter() {
1022 if let syn::TypeParamBound::Trait(trait_bound) = bound {
1023 if let syn::PathArguments::AngleBracketed(ref t) = &arguments {
1024 assert!(idx < t.args.len());
1025 if let syn::GenericArgument::Type(syn::Type::Path(p)) = &t.args[idx] {
1026 let generic_arg = types.resolve_path(&p.path, None);
1027 let generic_bound = types.resolve_path(&trait_bound.path, None);
1028 if let Some(traits_impld) = types.crate_types.trait_impls.get(&generic_arg) {
1029 for trait_impld in traits_impld {
1030 if *trait_impld == generic_bound { continue 'bounds_check; }
1032 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1033 continue 'alias_impls;
1035 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1036 continue 'alias_impls;
1038 } else { unimplemented!(); }
1039 } else { unimplemented!(); }
1040 } else { unimplemented!(); }
1043 syn::GenericParam::Lifetime(_) => {},
1044 syn::GenericParam::Const(_) => unimplemented!(),
1047 let aliased_impl = syn::ItemImpl {
1048 attrs: i.attrs.clone(),
1049 brace_token: syn::token::Brace(Span::call_site()),
1051 generics: syn::Generics {
1053 params: syn::punctuated::Punctuated::new(),
1057 impl_token: syn::Token![impl](Span::call_site()),
1058 items: i.items.clone(),
1059 self_ty: Box::new(syn::Type::Path(syn::TypePath { qself: None, path: alias.clone() })),
1060 trait_: i.trait_.clone(),
1063 writeln_impl(w, &aliased_impl, types);
1066 eprintln!("Not implementing anything for {} due to it being marked not exported", ident);
1069 eprintln!("Not implementing anything for {} due to no-resolve (probably the type isn't pub)", ident);
1076 /// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum
1077 /// is unitary), we generate an equivalent enum with all types replaced with their C mapped
1078 /// versions followed by conversion functions which map between the Rust version and the C mapped
1080 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) {
1081 match export_status(&e.attrs) {
1082 ExportStatus::Export => {},
1083 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1086 if is_enum_opaque(e) {
1087 eprintln!("Skipping enum {} as it contains non-unit fields", e.ident);
1088 writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers);
1091 writeln_docs(w, &e.attrs, "");
1093 if e.generics.lt_token.is_some() {
1097 let mut needs_free = false;
1099 writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap();
1100 for var in e.variants.iter() {
1101 assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum
1102 writeln_docs(w, &var.attrs, "\t");
1103 write!(w, "\t{}", var.ident).unwrap();
1104 if let syn::Fields::Named(fields) = &var.fields {
1106 writeln!(w, " {{").unwrap();
1107 for field in fields.named.iter() {
1108 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1109 writeln_docs(w, &field.attrs, "\t\t");
1110 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1111 types.write_c_type(w, &field.ty, None, false);
1112 writeln!(w, ",").unwrap();
1114 write!(w, "\t}}").unwrap();
1115 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1117 write!(w, "(").unwrap();
1118 for (idx, field) in fields.unnamed.iter().enumerate() {
1119 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1120 types.write_c_type(w, &field.ty, None, false);
1121 if idx != fields.unnamed.len() - 1 {
1122 write!(w, ",").unwrap();
1125 write!(w, ")").unwrap();
1127 if var.discriminant.is_some() { unimplemented!(); }
1128 writeln!(w, ",").unwrap();
1130 writeln!(w, "}}\nuse {}::{}::{} as native{};\nimpl {} {{", types.orig_crate, types.module_path, e.ident, e.ident, e.ident).unwrap();
1132 macro_rules! write_conv {
1133 ($fn_sig: expr, $to_c: expr, $ref: expr) => {
1134 writeln!(w, "\t#[allow(unused)]\n\tpub(crate) fn {} {{\n\t\tmatch {} {{", $fn_sig, if $to_c { "native" } else { "self" }).unwrap();
1135 for var in e.variants.iter() {
1136 write!(w, "\t\t\t{}{}::{} ", if $to_c { "native" } else { "" }, e.ident, var.ident).unwrap();
1137 if let syn::Fields::Named(fields) = &var.fields {
1138 write!(w, "{{").unwrap();
1139 for field in fields.named.iter() {
1140 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1141 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, field.ident.as_ref().unwrap()).unwrap();
1143 write!(w, "}} ").unwrap();
1144 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1145 write!(w, "(").unwrap();
1146 for (idx, field) in fields.unnamed.iter().enumerate() {
1147 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1148 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, ('a' as u8 + idx as u8) as char).unwrap();
1150 write!(w, ") ").unwrap();
1152 write!(w, "=>").unwrap();
1154 macro_rules! handle_field_a {
1155 ($field: expr, $field_ident: expr) => { {
1156 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1157 let mut sink = ::std::io::sink();
1158 let mut out: &mut dyn std::io::Write = if $ref { &mut sink } else { w };
1159 let new_var = if $to_c {
1160 types.write_to_c_conversion_new_var(&mut out, $field_ident, &$field.ty, None, false)
1162 types.write_from_c_conversion_new_var(&mut out, $field_ident, &$field.ty, None)
1164 if $ref || new_var {
1166 write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", $field_ident, $field_ident).unwrap();
1168 let nonref_ident = syn::Ident::new(&format!("{}_nonref", $field_ident), Span::call_site());
1170 types.write_to_c_conversion_new_var(w, &nonref_ident, &$field.ty, None, false);
1172 types.write_from_c_conversion_new_var(w, &nonref_ident, &$field.ty, None);
1174 write!(w, "\n\t\t\t\t").unwrap();
1177 write!(w, "\n\t\t\t\t").unwrap();
1182 if let syn::Fields::Named(fields) = &var.fields {
1183 write!(w, " {{\n\t\t\t\t").unwrap();
1184 for field in fields.named.iter() {
1185 handle_field_a!(field, field.ident.as_ref().unwrap());
1187 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1188 write!(w, " {{\n\t\t\t\t").unwrap();
1189 for (idx, field) in fields.unnamed.iter().enumerate() {
1190 handle_field_a!(field, &syn::Ident::new(&(('a' as u8 + idx as u8) as char).to_string(), Span::call_site()));
1192 } else { write!(w, " ").unwrap(); }
1194 write!(w, "{}{}::{}", if $to_c { "" } else { "native" }, e.ident, var.ident).unwrap();
1196 macro_rules! handle_field_b {
1197 ($field: expr, $field_ident: expr) => { {
1198 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1200 types.write_to_c_conversion_inline_prefix(w, &$field.ty, None, false);
1202 types.write_from_c_conversion_prefix(w, &$field.ty, None);
1204 write!(w, "{}{}", $field_ident,
1205 if $ref { "_nonref" } else { "" }).unwrap();
1207 types.write_to_c_conversion_inline_suffix(w, &$field.ty, None, false);
1209 types.write_from_c_conversion_suffix(w, &$field.ty, None);
1211 write!(w, ",").unwrap();
1215 if let syn::Fields::Named(fields) = &var.fields {
1216 write!(w, " {{").unwrap();
1217 for field in fields.named.iter() {
1218 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1219 write!(w, "\n\t\t\t\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1220 handle_field_b!(field, field.ident.as_ref().unwrap());
1222 writeln!(w, "\n\t\t\t\t}}").unwrap();
1223 write!(w, "\t\t\t}}").unwrap();
1224 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1225 write!(w, " (").unwrap();
1226 for (idx, field) in fields.unnamed.iter().enumerate() {
1227 write!(w, "\n\t\t\t\t\t").unwrap();
1228 handle_field_b!(field, &syn::Ident::new(&(('a' as u8 + idx as u8) as char).to_string(), Span::call_site()));
1230 writeln!(w, "\n\t\t\t\t)").unwrap();
1231 write!(w, "\t\t\t}}").unwrap();
1233 writeln!(w, ",").unwrap();
1235 writeln!(w, "\t\t}}\n\t}}").unwrap();
1239 write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true);
1240 write_conv!(format!("into_native(self) -> native{}", e.ident), false, false);
1241 write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true);
1242 write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false);
1243 writeln!(w, "}}").unwrap();
1246 writeln!(w, "/// Frees any resources used by the {}", e.ident).unwrap();
1247 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap();
1249 writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap();
1250 writeln!(w, "#[no_mangle]").unwrap();
1251 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap();
1252 writeln!(w, "\torig.clone()").unwrap();
1253 writeln!(w, "}}").unwrap();
1254 write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free);
1257 fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) {
1258 match export_status(&f.attrs) {
1259 ExportStatus::Export => {},
1260 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1262 writeln_docs(w, &f.attrs, "");
1264 let mut gen_types = GenericTypes::new();
1265 if !gen_types.learn_generics(&f.sig.generics, types) { return; }
1267 write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap();
1268 write_method_params(w, &f.sig, "", types, Some(&gen_types), false, true);
1269 write!(w, " {{\n\t").unwrap();
1270 write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false);
1271 write!(w, "{}::{}::{}(", types.orig_crate, types.module_path, f.sig.ident).unwrap();
1272 write_method_call_params(w, &f.sig, "", types, Some(&gen_types), "", false);
1273 writeln!(w, "\n}}\n").unwrap();
1276 // ********************************
1277 // *** File/Crate Walking Logic ***
1278 // ********************************
1281 pub attrs: Vec<syn::Attribute>,
1282 pub items: Vec<syn::Item>,
1283 pub submods: Vec<String>,
1285 /// A struct containing the syn::File AST for each file in the crate.
1286 struct FullLibraryAST {
1287 modules: HashMap<String, ASTModule, NonRandomHash>,
1289 impl FullLibraryAST {
1290 fn load_module(&mut self, module: String, attrs: Vec<syn::Attribute>, mut items: Vec<syn::Item>) {
1291 let mut non_mod_items = Vec::with_capacity(items.len());
1292 let mut submods = Vec::with_capacity(items.len());
1293 for item in items.drain(..) {
1295 syn::Item::Mod(m) if m.content.is_some() => {
1296 if export_status(&m.attrs) == ExportStatus::Export {
1297 if let syn::Visibility::Public(_) = m.vis {
1298 let modident = format!("{}", m.ident);
1299 let modname = if module != "" {
1300 module.clone() + "::" + &modident
1304 self.load_module(modname, m.attrs, m.content.unwrap().1);
1305 submods.push(modident);
1307 non_mod_items.push(syn::Item::Mod(m));
1311 syn::Item::Mod(_) => panic!("--pretty=expanded output should never have non-body modules"),
1312 _ => { non_mod_items.push(item); }
1315 self.modules.insert(module, ASTModule { attrs, items: non_mod_items, submods });
1318 pub fn load_lib(lib: syn::File) -> Self {
1319 assert_eq!(export_status(&lib.attrs), ExportStatus::Export);
1320 let mut res = Self { modules: HashMap::default() };
1321 res.load_module("".to_owned(), lib.attrs, lib.items);
1326 /// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at
1327 /// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST
1328 /// at `module` from C.
1329 fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>, out_dir: &str, orig_crate: &str, header_file: &mut File, cpp_header_file: &mut File) {
1330 for (module, astmod) in libast.modules.iter() {
1331 let ASTModule { ref attrs, ref items, ref submods } = astmod;
1332 assert_eq!(export_status(&attrs), ExportStatus::Export);
1334 let new_file_path = if submods.is_empty() {
1335 format!("{}/{}.rs", out_dir, module.replace("::", "/"))
1336 } else if module != "" {
1337 format!("{}/{}/mod.rs", out_dir, module.replace("::", "/"))
1339 format!("{}/lib.rs", out_dir)
1341 let _ = std::fs::create_dir((&new_file_path.as_ref() as &std::path::Path).parent().unwrap());
1342 let mut out = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1343 .open(new_file_path).expect("Unable to open new src file");
1345 writeln_docs(&mut out, &attrs, "");
1348 // Special-case the top-level lib.rs with various lint allows and a pointer to the c_types
1349 // and bitcoin hand-written modules.
1350 writeln!(out, "#![allow(unknown_lints)]").unwrap();
1351 writeln!(out, "#![allow(non_camel_case_types)]").unwrap();
1352 writeln!(out, "#![allow(non_snake_case)]").unwrap();
1353 writeln!(out, "#![allow(unused_imports)]").unwrap();
1354 writeln!(out, "#![allow(unused_variables)]").unwrap();
1355 writeln!(out, "#![allow(unused_mut)]").unwrap();
1356 writeln!(out, "#![allow(unused_parens)]").unwrap();
1357 writeln!(out, "#![allow(unused_unsafe)]").unwrap();
1358 writeln!(out, "#![allow(unused_braces)]").unwrap();
1359 writeln!(out, "#![deny(missing_docs)]").unwrap();
1360 writeln!(out, "mod c_types;").unwrap();
1361 writeln!(out, "mod bitcoin;").unwrap();
1363 writeln!(out, "\nuse std::ffi::c_void;\nuse bitcoin::hashes::Hash;\nuse crate::c_types::*;\n").unwrap();
1367 writeln!(out, "pub mod {};", m).unwrap();
1370 eprintln!("Converting {} entries...", module);
1372 let import_resolver = ImportResolver::new(module, items);
1373 let mut type_resolver = TypeResolver::new(orig_crate, module, import_resolver, crate_types);
1375 for item in items.iter() {
1377 syn::Item::Use(_) => {}, // Handled above
1378 syn::Item::Static(_) => {},
1379 syn::Item::Enum(e) => {
1380 if let syn::Visibility::Public(_) = e.vis {
1381 writeln_enum(&mut out, &e, &mut type_resolver, header_file, cpp_header_file);
1384 syn::Item::Impl(i) => {
1385 writeln_impl(&mut out, &i, &mut type_resolver);
1387 syn::Item::Struct(s) => {
1388 if let syn::Visibility::Public(_) = s.vis {
1389 writeln_struct(&mut out, &s, &mut type_resolver, header_file, cpp_header_file);
1392 syn::Item::Trait(t) => {
1393 if let syn::Visibility::Public(_) = t.vis {
1394 writeln_trait(&mut out, &t, &mut type_resolver, header_file, cpp_header_file);
1397 syn::Item::Mod(_) => {}, // We don't have to do anything - the top loop handles these.
1398 syn::Item::Const(c) => {
1399 // Re-export any primitive-type constants.
1400 if let syn::Visibility::Public(_) = c.vis {
1401 if let syn::Type::Path(p) = &*c.ty {
1402 let resolved_path = type_resolver.resolve_path(&p.path, None);
1403 if type_resolver.is_primitive(&resolved_path) {
1404 writeln_docs(&mut out, &c.attrs, "");
1405 writeln!(out, "\n#[no_mangle]").unwrap();
1406 writeln!(out, "pub static {}: {} = {}::{}::{};", c.ident, resolved_path, orig_crate, module, c.ident).unwrap();
1411 syn::Item::Type(t) => {
1412 if let syn::Visibility::Public(_) = t.vis {
1413 match export_status(&t.attrs) {
1414 ExportStatus::Export => {},
1415 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1418 let mut process_alias = true;
1419 for tok in t.generics.params.iter() {
1420 if let syn::GenericParam::Lifetime(_) = tok {}
1421 else { process_alias = false; }
1425 syn::Type::Path(_) =>
1426 writeln_opaque(&mut out, &t.ident, &format!("{}", t.ident), &t.generics, &t.attrs, &type_resolver, header_file, cpp_header_file),
1432 syn::Item::Fn(f) => {
1433 if let syn::Visibility::Public(_) = f.vis {
1434 writeln_fn(&mut out, &f, &mut type_resolver);
1437 syn::Item::Macro(m) => {
1438 if m.ident.is_none() { // If its not a macro definition
1439 convert_macro(&mut out, &m.mac.path, &m.mac.tokens, &type_resolver);
1442 syn::Item::Verbatim(_) => {},
1443 syn::Item::ExternCrate(_) => {},
1444 _ => unimplemented!(),
1448 out.flush().unwrap();
1452 fn walk_private_mod<'a>(module: String, items: &'a syn::ItemMod, crate_types: &mut CrateTypes<'a>) {
1453 let import_resolver = ImportResolver::new(&module, &items.content.as_ref().unwrap().1);
1454 for item in items.content.as_ref().unwrap().1.iter() {
1456 syn::Item::Mod(m) => walk_private_mod(format!("{}::{}", module, m.ident), m, crate_types),
1457 syn::Item::Impl(i) => {
1458 if let &syn::Type::Path(ref p) = &*i.self_ty {
1459 if let Some(trait_path) = i.trait_.as_ref() {
1460 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1461 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1462 match crate_types.trait_impls.entry(sp) {
1463 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1464 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1476 /// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes.
1477 fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) {
1478 for (module, astmod) in ast_storage.modules.iter() {
1479 let ASTModule { ref attrs, ref items, submods: _ } = astmod;
1480 assert_eq!(export_status(&attrs), ExportStatus::Export);
1481 let import_resolver = ImportResolver::new(module, items);
1483 for item in items.iter() {
1485 syn::Item::Struct(s) => {
1486 if let syn::Visibility::Public(_) = s.vis {
1487 match export_status(&s.attrs) {
1488 ExportStatus::Export => {},
1489 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1491 let struct_path = format!("{}::{}", module, s.ident);
1492 crate_types.opaques.insert(struct_path, &s.ident);
1495 syn::Item::Trait(t) => {
1496 if let syn::Visibility::Public(_) = t.vis {
1497 match export_status(&t.attrs) {
1498 ExportStatus::Export => {},
1499 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1501 let trait_path = format!("{}::{}", module, t.ident);
1502 walk_supertraits!(t, None, (
1504 crate_types.clonable_types.insert("crate::".to_owned() + &trait_path);
1508 crate_types.traits.insert(trait_path, &t);
1511 syn::Item::Type(t) => {
1512 if let syn::Visibility::Public(_) = t.vis {
1513 match export_status(&t.attrs) {
1514 ExportStatus::Export => {},
1515 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1517 let type_path = format!("{}::{}", module, t.ident);
1518 let mut process_alias = true;
1519 for tok in t.generics.params.iter() {
1520 if let syn::GenericParam::Lifetime(_) = tok {}
1521 else { process_alias = false; }
1525 syn::Type::Path(p) => {
1526 // If its a path with no generics, assume we don't map the aliased type and map it opaque
1527 let mut segments = syn::punctuated::Punctuated::new();
1528 segments.push(syn::PathSegment {
1529 ident: t.ident.clone(),
1530 arguments: syn::PathArguments::None,
1532 let path_obj = syn::Path { leading_colon: None, segments };
1533 let args_obj = p.path.segments.last().unwrap().arguments.clone();
1534 match crate_types.reverse_alias_map.entry(import_resolver.maybe_resolve_path(&p.path, None).unwrap()) {
1535 hash_map::Entry::Occupied(mut e) => { e.get_mut().push((path_obj, args_obj)); },
1536 hash_map::Entry::Vacant(e) => { e.insert(vec![(path_obj, args_obj)]); },
1539 crate_types.opaques.insert(type_path.clone(), &t.ident);
1542 crate_types.type_aliases.insert(type_path, import_resolver.resolve_imported_refs((*t.ty).clone()));
1548 syn::Item::Enum(e) if is_enum_opaque(e) => {
1549 if let syn::Visibility::Public(_) = e.vis {
1550 match export_status(&e.attrs) {
1551 ExportStatus::Export => {},
1552 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1554 let enum_path = format!("{}::{}", module, e.ident);
1555 crate_types.opaques.insert(enum_path, &e.ident);
1558 syn::Item::Enum(e) => {
1559 if let syn::Visibility::Public(_) = e.vis {
1560 match export_status(&e.attrs) {
1561 ExportStatus::Export => {},
1562 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1564 let enum_path = format!("{}::{}", module, e.ident);
1565 crate_types.mirrored_enums.insert(enum_path, &e);
1568 syn::Item::Impl(i) => {
1569 if let &syn::Type::Path(ref p) = &*i.self_ty {
1570 if let Some(trait_path) = i.trait_.as_ref() {
1571 if path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) {
1572 if let Some(full_path) = import_resolver.maybe_resolve_path(&p.path, None) {
1573 crate_types.clonable_types.insert("crate::".to_owned() + &full_path);
1576 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1577 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1578 match crate_types.trait_impls.entry(sp) {
1579 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1580 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1587 syn::Item::Mod(m) => walk_private_mod(format!("{}::{}", module, m.ident), m, crate_types),
1595 let args: Vec<String> = env::args().collect();
1596 if args.len() != 6 {
1597 eprintln!("Usage: target/dir source_crate_name derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
1601 let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1602 .open(&args[3]).expect("Unable to open new header file");
1603 let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1604 .open(&args[4]).expect("Unable to open new header file");
1605 let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1606 .open(&args[5]).expect("Unable to open new header file");
1608 writeln!(header_file, "#if defined(__GNUC__)").unwrap();
1609 writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
1610 writeln!(header_file, "#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
1611 writeln!(header_file, "#else").unwrap();
1612 writeln!(header_file, "#define MUST_USE_STRUCT").unwrap();
1613 writeln!(header_file, "#define MUST_USE_RES").unwrap();
1614 writeln!(header_file, "#endif").unwrap();
1615 writeln!(header_file, "#if defined(__clang__)").unwrap();
1616 writeln!(header_file, "#define NONNULL_PTR _Nonnull").unwrap();
1617 writeln!(header_file, "#else").unwrap();
1618 writeln!(header_file, "#define NONNULL_PTR").unwrap();
1619 writeln!(header_file, "#endif").unwrap();
1620 writeln!(cpp_header_file, "#include <string.h>\nnamespace LDK {{").unwrap();
1622 // First parse the full crate's ASTs, caching them so that we can hold references to the AST
1623 // objects in other datastructures:
1624 let mut lib_src = String::new();
1625 std::io::stdin().lock().read_to_string(&mut lib_src).unwrap();
1626 let lib_syntax = syn::parse_file(&lib_src).expect("Unable to parse file");
1627 let libast = FullLibraryAST::load_lib(lib_syntax);
1629 // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
1630 // when parsing other file ASTs...
1631 let mut libtypes = CrateTypes { traits: HashMap::new(), opaques: HashMap::new(), mirrored_enums: HashMap::new(),
1632 type_aliases: HashMap::new(), reverse_alias_map: HashMap::new(), templates_defined: HashMap::default(),
1633 template_file: &mut derived_templates,
1634 clonable_types: HashSet::new(), trait_impls: HashMap::new() };
1635 walk_ast(&libast, &mut libtypes);
1637 // ... finally, do the actual file conversion/mapping, writing out types as we go.
1638 convert_file(&libast, &mut libtypes, &args[1], &args[2], &mut header_file, &mut cpp_header_file);
1640 // For container templates which we created while walking the crate, make sure we add C++
1641 // mapped types so that C++ users can utilize the auto-destructors available.
1642 for (ty, has_destructor) in libtypes.templates_defined.iter() {
1643 write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor);
1645 writeln!(cpp_header_file, "}}").unwrap();
1647 header_file.flush().unwrap();
1648 cpp_header_file.flush().unwrap();
1649 derived_templates.flush().unwrap();