1 // This file is Copyright its original authors, visible in version control
4 // This file is licensed under the Apache License, Version 2.0 <LICENSE-APACHE>
5 // or the MIT license <LICENSE-MIT>, at your option.
6 // You may not use this file except in accordance with one or both of these
9 //! Converts a rust crate into a rust crate containing a number of C-exported wrapper functions and
10 //! classes (which is exportable using cbindgen).
11 //! In general, supports convering:
12 //! * structs as a pointer to the underlying type (either owned or not owned),
13 //! * traits as a void-ptr plus a jump table,
14 //! * enums as an equivalent enum with all the inner fields mapped to the mapped types,
15 //! * certain containers (tuples, slices, Vecs, Options, and Results currently) to a concrete
16 //! version of a defined container template.
18 //! It also generates relevant memory-management functions and free-standing functions with
19 //! parameters mapped.
21 use std::collections::{HashMap, hash_map};
24 use std::io::{Read, Write};
27 use proc_macro2::Span;
28 use quote::format_ident;
36 const DEFAULT_IMPORTS: &'static str = "\nuse std::str::FromStr;\nuse std::ffi::c_void;\nuse bitcoin::hashes::Hash;\nuse crate::c_types::*;\n";
38 // *************************************
39 // *** Manually-expanded conversions ***
40 // *************************************
42 /// Convert "impl trait_path for for_ty { .. }" for manually-mapped types (ie (de)serialization)
43 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) {
44 if let Some(t) = types.maybe_resolve_path(&trait_path, Some(generics)) {
47 let mut has_inner = false;
48 if let syn::Type::Path(ref p) = for_ty {
49 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
50 for_obj = format!("{}", ident);
51 full_obj_path = for_obj.clone();
52 has_inner = types.c_type_has_inner_from_path(&types.resolve_path(&p.path, Some(generics)));
55 // We assume that anything that isn't a Path is somehow a generic that ends up in our
56 // derived-types module.
57 let mut for_obj_vec = Vec::new();
58 types.write_c_type(&mut for_obj_vec, for_ty, Some(generics), false);
59 full_obj_path = String::from_utf8(for_obj_vec).unwrap();
60 assert!(full_obj_path.starts_with(TypeResolver::generated_container_path()));
61 for_obj = full_obj_path[TypeResolver::generated_container_path().len() + 2..].into();
65 "lightning::util::ser::Writeable" => {
66 writeln!(w, "#[no_mangle]").unwrap();
67 writeln!(w, "/// Serialize the {} object into a byte array which can be read by {}_read", for_obj, for_obj).unwrap();
68 writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, full_obj_path).unwrap();
70 let ref_type: syn::Type = syn::parse_quote!(&#for_ty);
71 assert!(!types.write_from_c_conversion_new_var(w, &format_ident!("obj"), &ref_type, Some(generics)));
73 write!(w, "\tcrate::c_types::serialize_obj(").unwrap();
74 types.write_from_c_conversion_prefix(w, &ref_type, Some(generics));
75 write!(w, "unsafe {{ &*obj }}").unwrap();
76 types.write_from_c_conversion_suffix(w, &ref_type, Some(generics));
77 writeln!(w, ")").unwrap();
79 writeln!(w, "}}").unwrap();
81 writeln!(w, "#[no_mangle]").unwrap();
82 writeln!(w, "pub(crate) extern \"C\" fn {}_write_void(obj: *const c_void) -> crate::c_types::derived::CVec_u8Z {{", for_obj).unwrap();
83 writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &*(obj as *const native{}) }})", for_obj).unwrap();
84 writeln!(w, "}}").unwrap();
87 "lightning::util::ser::Readable"|"lightning::util::ser::ReadableArgs" => {
88 // Create the Result<Object, DecodeError> syn::Type
89 let res_ty: syn::Type = parse_quote!(Result<#for_ty, ::ln::msgs::DecodeError>);
91 writeln!(w, "#[no_mangle]").unwrap();
92 writeln!(w, "/// Read a {} from a byte array, created by {}_write", for_obj, for_obj).unwrap();
93 write!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice", for_obj).unwrap();
95 let mut arg_conv = Vec::new();
96 if t == "lightning::util::ser::ReadableArgs" {
97 write!(w, ", arg: ").unwrap();
98 assert!(trait_path.leading_colon.is_none());
99 let args_seg = trait_path.segments.iter().last().unwrap();
100 assert_eq!(format!("{}", args_seg.ident), "ReadableArgs");
101 if let syn::PathArguments::AngleBracketed(args) = &args_seg.arguments {
102 assert_eq!(args.args.len(), 1);
103 if let syn::GenericArgument::Type(args_ty) = args.args.iter().next().unwrap() {
104 types.write_c_type(w, args_ty, Some(generics), false);
106 assert!(!types.write_from_c_conversion_new_var(&mut arg_conv, &format_ident!("arg"), &args_ty, Some(generics)));
108 write!(&mut arg_conv, "\tlet arg_conv = ").unwrap();
109 types.write_from_c_conversion_prefix(&mut arg_conv, &args_ty, Some(generics));
110 write!(&mut arg_conv, "arg").unwrap();
111 types.write_from_c_conversion_suffix(&mut arg_conv, &args_ty, Some(generics));
112 } else { unreachable!(); }
113 } else { unreachable!(); }
115 write!(w, ") -> ").unwrap();
116 types.write_c_type(w, &res_ty, Some(generics), false);
117 writeln!(w, " {{").unwrap();
119 if t == "lightning::util::ser::ReadableArgs" {
120 w.write(&arg_conv).unwrap();
121 write!(w, ";\n\tlet res: ").unwrap();
122 // At least in one case we need type annotations here, so provide them.
123 types.write_rust_type(w, Some(generics), &res_ty);
124 writeln!(w, " = crate::c_types::deserialize_obj_arg(ser, arg_conv);").unwrap();
126 writeln!(w, "\tlet res = crate::c_types::deserialize_obj(ser);").unwrap();
128 write!(w, "\t").unwrap();
129 if types.write_to_c_conversion_new_var(w, &format_ident!("res"), &res_ty, Some(generics), false) {
130 write!(w, "\n\t").unwrap();
132 types.write_to_c_conversion_inline_prefix(w, &res_ty, Some(generics), false);
133 write!(w, "res").unwrap();
134 types.write_to_c_conversion_inline_suffix(w, &res_ty, Some(generics), false);
135 writeln!(w, "\n}}").unwrap();
142 /// Convert "TraitA : TraitB" to a single function name and return type.
144 /// This is (obviously) somewhat over-specialized and only useful for TraitB's that only require a
145 /// single function (eg for serialization).
146 fn convert_trait_impl_field(trait_path: &str) -> (&'static str, String, &'static str) {
148 "lightning::util::ser::Writeable" => ("Serialize the object into a byte array", "write".to_owned(), "crate::c_types::derived::CVec_u8Z"),
149 _ => unimplemented!(),
153 /// Companion to convert_trait_impl_field, write an assignment for the function defined by it for
154 /// `for_obj` which implements the the trait at `trait_path`.
155 fn write_trait_impl_field_assign<W: std::io::Write>(w: &mut W, trait_path: &str, for_obj: &syn::Ident) {
157 "lightning::util::ser::Writeable" => {
158 writeln!(w, "\t\twrite: {}_write_void,", for_obj).unwrap();
160 _ => unimplemented!(),
164 /// Write out the impl block for a defined trait struct which has a supertrait
165 fn do_write_impl_trait<W: std::io::Write>(w: &mut W, trait_path: &str, _trait_name: &syn::Ident, for_obj: &str) {
166 eprintln!("{}", trait_path);
168 "lightning::util::ser::Writeable" => {
169 writeln!(w, "impl {} for {} {{", trait_path, for_obj).unwrap();
170 writeln!(w, "\tfn write<W: lightning::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {{").unwrap();
171 writeln!(w, "\t\tlet vec = (self.write)(self.this_arg);").unwrap();
172 writeln!(w, "\t\tw.write_all(vec.as_slice())").unwrap();
173 writeln!(w, "\t}}\n}}").unwrap();
179 // *******************************
180 // *** Per-Type Printing Logic ***
181 // *******************************
183 macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $pat: pat => $e: expr),*) ) => { {
184 if $t.colon_token.is_some() {
185 for st in $t.supertraits.iter() {
187 syn::TypeParamBound::Trait(supertrait) => {
188 if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() {
191 // First try to resolve path to find in-crate traits, but if that doesn't work
192 // assume its a prelude trait (eg Clone, etc) and just use the single ident.
193 let types_opt: Option<&TypeResolver> = $types;
194 if let Some(types) = types_opt {
195 if let Some(path) = types.maybe_resolve_path(&supertrait.path, None) {
196 match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
202 if let Some(ident) = supertrait.path.get_ident() {
203 match (&format!("{}", ident) as &str, &ident) {
206 } else if types_opt.is_some() {
207 panic!("Supertrait unresolvable and not single-ident");
210 syn::TypeParamBound::Lifetime(_) => unimplemented!(),
216 /// Prints a C-mapped trait object containing a void pointer and a jump table for each function in
217 /// the original trait.
218 /// Implements the native Rust trait and relevant parent traits for the new C-mapped trait.
220 /// Finally, implements Deref<MappedTrait> for MappedTrait which allows its use in types which need
221 /// a concrete Deref to the Rust trait.
222 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) {
223 let trait_name = format!("{}", t.ident);
224 match export_status(&t.attrs) {
225 ExportStatus::Export => {},
226 ExportStatus::NoExport|ExportStatus::TestOnly => return,
228 writeln_docs(w, &t.attrs, "");
230 let mut gen_types = GenericTypes::new(None);
231 assert!(gen_types.learn_generics(&t.generics, types));
232 gen_types.learn_associated_types(&t, types);
234 writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap();
235 writeln!(w, "\t/// An opaque pointer which is passed to your function implementations as an argument.").unwrap();
236 writeln!(w, "\t/// This has no meaning in the LDK, and can be NULL or any other value.").unwrap();
237 writeln!(w, "\tpub this_arg: *mut c_void,").unwrap();
238 let mut generated_fields = Vec::new(); // Every field's (name, is_clonable) except this_arg, used in Clone generation
239 for item in t.items.iter() {
241 &syn::TraitItem::Method(ref m) => {
242 match export_status(&m.attrs) {
243 ExportStatus::NoExport => {
244 // NoExport in this context means we'll hit an unimplemented!() at runtime,
248 ExportStatus::Export => {},
249 ExportStatus::TestOnly => continue,
251 if m.default.is_some() { unimplemented!(); }
253 let mut meth_gen_types = gen_types.push_ctx();
254 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
256 writeln_docs(w, &m.attrs, "\t");
258 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
259 if let syn::Type::Reference(r) = &**rtype {
260 // We have to do quite a dance for trait functions which return references
261 // - they ultimately require us to have a native Rust object stored inside
262 // our concrete trait to return a reference to. However, users may wish to
263 // update the value to be returned each time the function is called (or, to
264 // make C copies of Rust impls equivalent, we have to be able to).
266 // Thus, we store a copy of the C-mapped type (which is just a pointer to
267 // the Rust type and a flag to indicate whether deallocation needs to
268 // happen) as well as provide an Option<>al function pointer which is
269 // called when the trait method is called which allows updating on the fly.
270 write!(w, "\tpub {}: ", m.sig.ident).unwrap();
271 generated_fields.push((format!("{}", m.sig.ident), true));
272 types.write_c_type(w, &*r.elem, Some(&meth_gen_types), false);
273 writeln!(w, ",").unwrap();
274 writeln!(w, "\t/// Fill in the {} field as a reference to it will be given to Rust after this returns", m.sig.ident).unwrap();
275 writeln!(w, "\t/// Note that this takes a pointer to this object, not the this_ptr like other methods do").unwrap();
276 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();
277 writeln!(w, "\tpub set_{}: Option<extern \"C\" fn(&{})>,", m.sig.ident, trait_name).unwrap();
278 generated_fields.push((format!("set_{}", m.sig.ident), true));
279 // Note that cbindgen will now generate
280 // typedef struct Thing {..., set_thing: (const Thing*), ...} Thing;
281 // which does not compile since Thing is not defined before it is used.
282 writeln!(extra_headers, "struct LDK{};", trait_name).unwrap();
283 writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap();
286 // Sadly, this currently doesn't do what we want, but it should be easy to get
287 // cbindgen to support it. See https://github.com/eqrion/cbindgen/issues/531
288 writeln!(w, "\t#[must_use]").unwrap();
291 write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap();
292 generated_fields.push((format!("{}", m.sig.ident), true));
293 write_method_params(w, &m.sig, "c_void", types, Some(&meth_gen_types), true, false);
294 writeln!(w, ",").unwrap();
296 &syn::TraitItem::Type(_) => {},
297 _ => unimplemented!(),
300 // Add functions which may be required for supertrait implementations.
301 let mut requires_clone = false;
302 walk_supertraits!(t, Some(&types), (
303 ("Clone", _) => requires_clone = true,
306 walk_supertraits!(t, Some(&types), (
308 writeln!(w, "\t/// Creates a copy of the object pointed to by this_arg, for a copy of this {}.", trait_name).unwrap();
309 writeln!(w, "\t/// Note that the ultimate copy of the {} will have all function pointers the same as the original.", trait_name).unwrap();
310 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();
311 writeln!(w, "\tpub clone: Option<extern \"C\" fn (this_arg: *const c_void) -> *mut c_void>,").unwrap();
312 generated_fields.push(("clone".to_owned(), true));
314 ("std::cmp::Eq", _) => {
315 writeln!(w, "\t/// Checks if two objects are equal given this object's this_arg pointer and another object.").unwrap();
316 writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap();
317 writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap();
318 generated_fields.push(("eq".to_owned(), true));
320 ("std::hash::Hash", _) => {
321 writeln!(w, "\t/// Calculate a succinct non-cryptographic hash for an object given its this_arg pointer.").unwrap();
322 writeln!(w, "\t/// This is used, for example, for inclusion of this object in a hash map.").unwrap();
323 writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap();
324 generated_fields.push(("hash".to_owned(), true));
326 ("Send", _) => {}, ("Sync", _) => {},
328 generated_fields.push(if types.crate_types.traits.get(s).is_none() {
329 let (docs, name, ret) = convert_trait_impl_field(s);
330 writeln!(w, "\t/// {}", docs).unwrap();
331 writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap();
332 (name, true) // Assume clonable
334 // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
335 writeln!(w, "\t/// Implementation of {} for this object.", i).unwrap();
336 writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
337 let is_clonable = types.is_clonable(s);
338 if !is_clonable && requires_clone {
339 writeln!(w, "\t/// Creates a copy of the {}, for a copy of this {}.", i, trait_name).unwrap();
340 writeln!(w, "\t/// Because {} doesn't natively support copying itself, you have to provide a full copy implementation here.", i).unwrap();
341 writeln!(w, "\tpub {}_clone: extern \"C\" fn (orig_{}: &{}) -> {},", i, i, i, i).unwrap();
343 (format!("{}", i), is_clonable)
347 writeln!(w, "\t/// Frees any resources associated with this object given its this_arg pointer.").unwrap();
348 writeln!(w, "\t/// Does not need to free the outer struct containing function pointers and may be NULL is no resources need to be freed.").unwrap();
349 writeln!(w, "\tpub free: Option<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
350 generated_fields.push(("free".to_owned(), true));
351 writeln!(w, "}}").unwrap();
353 macro_rules! impl_trait_for_c {
354 ($t: expr, $impl_accessor: expr, $type_resolver: expr) => {
355 for item in $t.items.iter() {
357 syn::TraitItem::Method(m) => {
358 if let ExportStatus::TestOnly = export_status(&m.attrs) { continue; }
359 if m.default.is_some() { unimplemented!(); }
360 if m.sig.constness.is_some() || m.sig.asyncness.is_some() || m.sig.unsafety.is_some() ||
361 m.sig.abi.is_some() || m.sig.variadic.is_some() {
364 let mut meth_gen_types = gen_types.push_ctx();
365 assert!(meth_gen_types.learn_generics(&m.sig.generics, $type_resolver));
366 write!(w, "\tfn {}", m.sig.ident).unwrap();
367 $type_resolver.write_rust_generic_param(w, Some(&meth_gen_types), m.sig.generics.params.iter());
368 write!(w, "(").unwrap();
369 for inp in m.sig.inputs.iter() {
371 syn::FnArg::Receiver(recv) => {
372 if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
373 write!(w, "&").unwrap();
374 if let Some(lft) = &recv.reference.as_ref().unwrap().1 {
375 write!(w, "'{} ", lft.ident).unwrap();
377 if recv.mutability.is_some() {
378 write!(w, "mut self").unwrap();
380 write!(w, "self").unwrap();
383 syn::FnArg::Typed(arg) => {
384 if !arg.attrs.is_empty() { unimplemented!(); }
386 syn::Pat::Ident(ident) => {
387 if !ident.attrs.is_empty() || ident.by_ref.is_some() ||
388 ident.mutability.is_some() || ident.subpat.is_some() {
391 write!(w, ", {}{}: ", if $type_resolver.skip_arg(&*arg.ty, Some(&meth_gen_types)) { "_" } else { "" }, ident.ident).unwrap();
393 _ => unimplemented!(),
395 $type_resolver.write_rust_type(w, Some(&meth_gen_types), &*arg.ty);
399 write!(w, ")").unwrap();
400 match &m.sig.output {
401 syn::ReturnType::Type(_, rtype) => {
402 write!(w, " -> ").unwrap();
403 $type_resolver.write_rust_type(w, Some(&meth_gen_types), &*rtype)
407 write!(w, " {{\n\t\t").unwrap();
408 match export_status(&m.attrs) {
409 ExportStatus::NoExport => {
414 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
415 if let syn::Type::Reference(r) = &**rtype {
416 assert_eq!(m.sig.inputs.len(), 1); // Must only take self!
417 writeln!(w, "if let Some(f) = self{}.set_{} {{", $impl_accessor, m.sig.ident).unwrap();
418 writeln!(w, "\t\t\t(f)(&self{});", $impl_accessor).unwrap();
419 write!(w, "\t\t}}\n\t\t").unwrap();
420 $type_resolver.write_from_c_conversion_to_ref_prefix(w, &*r.elem, Some(&meth_gen_types));
421 write!(w, "self{}.{}", $impl_accessor, m.sig.ident).unwrap();
422 $type_resolver.write_from_c_conversion_to_ref_suffix(w, &*r.elem, Some(&meth_gen_types));
423 writeln!(w, "\n\t}}").unwrap();
427 write_method_var_decl_body(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), true);
428 write!(w, "(self{}.{})(", $impl_accessor, m.sig.ident).unwrap();
429 write_method_call_params(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), "", true);
431 writeln!(w, "\n\t}}").unwrap();
433 &syn::TraitItem::Type(ref t) => {
434 if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); }
435 let mut bounds_iter = t.bounds.iter();
436 match bounds_iter.next().unwrap() {
437 syn::TypeParamBound::Trait(tr) => {
438 writeln!(w, "\ttype {} = crate::{};", t.ident, $type_resolver.resolve_path(&tr.path, Some(&gen_types))).unwrap();
440 _ => unimplemented!(),
442 if bounds_iter.next().is_some() { unimplemented!(); }
444 _ => unimplemented!(),
451 // Implement supertraits for the C-mapped struct.
452 walk_supertraits!(t, Some(&types), (
453 ("Send", _) => writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(),
454 ("Sync", _) => writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(),
455 ("std::cmp::Eq", _) => {
456 writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap();
457 writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap();
458 writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o) }}\n}}").unwrap();
460 ("std::hash::Hash", _) => {
461 writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap();
462 writeln!(w, "\tfn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap();
465 writeln!(w, "#[no_mangle]").unwrap();
466 writeln!(w, "/// Creates a copy of a {}", trait_name).unwrap();
467 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
468 writeln!(w, "\t{} {{", trait_name).unwrap();
469 writeln!(w, "\t\tthis_arg: if let Some(f) = orig.clone {{ (f)(orig.this_arg) }} else {{ orig.this_arg }},").unwrap();
470 for (field, clonable) in generated_fields.iter() {
472 writeln!(w, "\t\t{}: Clone::clone(&orig.{}),", field, field).unwrap();
474 writeln!(w, "\t\t{}: (orig.{}_clone)(&orig.{}),", field, field, field).unwrap();
475 writeln!(w, "\t\t{}_clone: orig.{}_clone,", field, field).unwrap();
478 writeln!(w, "\t}}\n}}").unwrap();
479 writeln!(w, "impl Clone for {} {{", trait_name).unwrap();
480 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
481 writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap();
482 writeln!(w, "\t}}\n}}").unwrap();
485 if let Some(supertrait) = types.crate_types.traits.get(s) {
486 let mut module_iter = s.rsplitn(2, "::");
487 module_iter.next().unwrap();
488 let supertrait_module = module_iter.next().unwrap();
489 let imports = ImportResolver::new(supertrait_module.splitn(2, "::").next().unwrap(), &types.crate_types.lib_ast.dependencies,
490 supertrait_module, &types.crate_types.lib_ast.modules.get(supertrait_module).unwrap().items);
491 let resolver = TypeResolver::new(&supertrait_module, imports, types.crate_types);
492 writeln!(w, "impl {} for {} {{", s, trait_name).unwrap();
493 impl_trait_for_c!(supertrait, format!(".{}", i), &resolver);
494 writeln!(w, "}}").unwrap();
495 walk_supertraits!(supertrait, Some(&types), (
496 ("Send", _) => writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(),
497 ("Sync", _) => writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(),
498 _ => unimplemented!()
501 do_write_impl_trait(w, s, i, &trait_name);
506 // Finally, implement the original Rust trait for the newly created mapped trait.
507 writeln!(w, "\nuse {}::{} as rust{};", types.module_path, t.ident, trait_name).unwrap();
508 write!(w, "impl rust{}", t.ident).unwrap();
509 maybe_write_generics(w, &t.generics, types, false);
510 writeln!(w, " for {} {{", trait_name).unwrap();
511 impl_trait_for_c!(t, "", types);
512 writeln!(w, "}}\n").unwrap();
513 writeln!(w, "// We're essentially a pointer already, or at least a set of pointers, so allow us to be used").unwrap();
514 writeln!(w, "// directly as a Deref trait in higher-level structs:").unwrap();
515 writeln!(w, "impl std::ops::Deref for {} {{\n\ttype Target = Self;", trait_name).unwrap();
516 writeln!(w, "\tfn deref(&self) -> &Self {{\n\t\tself\n\t}}\n}}").unwrap();
518 writeln!(w, "/// Calls the free function if one is set").unwrap();
519 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", trait_name, trait_name).unwrap();
520 writeln!(w, "impl Drop for {} {{", trait_name).unwrap();
521 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
522 writeln!(w, "\t\tif let Some(f) = self.free {{").unwrap();
523 writeln!(w, "\t\t\tf(self.this_arg);").unwrap();
524 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
526 write_cpp_wrapper(cpp_headers, &trait_name, true);
529 /// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type
530 /// and a flag to indicate whether Drop'ing the mapped struct drops the underlying Rust type.
532 /// Also writes out a _free function and a C++ wrapper which handles calling _free.
533 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) {
534 // If we directly read the original type by its original name, cbindgen hits
535 // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary
536 // name and then reference it by that name, which works around the issue.
537 write!(w, "\nuse {}::{} as native{}Import;\ntype native{} = native{}Import", types.module_path, ident, ident, ident, ident).unwrap();
538 maybe_write_generics(w, &generics, &types, true);
539 writeln!(w, ";\n").unwrap();
540 writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap();
541 writeln_docs(w, &attrs, "");
542 writeln!(w, "#[must_use]\n#[repr(C)]\npub struct {} {{", struct_name).unwrap();
543 writeln!(w, "\t/// A pointer to the opaque Rust object.\n").unwrap();
544 writeln!(w, "\t/// Nearly everywhere, inner must be non-null, however in places where").unwrap();
545 writeln!(w, "\t/// the Rust equivalent takes an Option, it may be set to null to indicate None.").unwrap();
546 writeln!(w, "\tpub inner: *mut native{},", ident).unwrap();
547 writeln!(w, "\t/// Indicates that this is the only struct which contains the same pointer.\n").unwrap();
548 writeln!(w, "\t/// Rust functions which take ownership of an object provided via an argument require").unwrap();
549 writeln!(w, "\t/// this to be true and invalidate the object pointed to by inner.").unwrap();
550 writeln!(w, "\tpub is_owned: bool,").unwrap();
551 writeln!(w, "}}\n").unwrap();
552 writeln!(w, "impl Drop for {} {{\n\tfn drop(&mut self) {{", struct_name).unwrap();
553 writeln!(w, "\t\tif self.is_owned && !<*mut native{}>::is_null(self.inner) {{", ident).unwrap();
554 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(self.inner) }};\n\t\t}}\n\t}}\n}}").unwrap();
555 writeln!(w, "/// Frees any resources used by the {}, if is_owned is set and inner is non-NULL.", struct_name).unwrap();
556 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_obj: {}) {{ }}", struct_name, struct_name).unwrap();
557 writeln!(w, "#[allow(unused)]").unwrap();
558 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
559 writeln!(w, "extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
560 writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap();
561 writeln!(w, "#[allow(unused)]").unwrap();
562 writeln!(w, "/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap();
563 writeln!(w, "impl {} {{", struct_name).unwrap();
564 writeln!(w, "\tpub(crate) fn take_inner(mut self) -> *mut native{} {{", struct_name).unwrap();
565 writeln!(w, "\t\tassert!(self.is_owned);").unwrap();
566 writeln!(w, "\t\tlet ret = self.inner;").unwrap();
567 writeln!(w, "\t\tself.inner = std::ptr::null_mut();").unwrap();
568 writeln!(w, "\t\tret").unwrap();
569 writeln!(w, "\t}}\n}}").unwrap();
571 write_cpp_wrapper(cpp_headers, &format!("{}", ident), true);
574 /// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
575 /// the struct itself, and then writing getters and setters for public, understood-type fields and
576 /// a constructor if every field is public.
577 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) {
578 if export_status(&s.attrs) != ExportStatus::Export { return; }
580 let struct_name = &format!("{}", s.ident);
581 writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers);
583 if let syn::Fields::Named(fields) = &s.fields {
584 let mut self_path_segs = syn::punctuated::Punctuated::new();
585 self_path_segs.push(s.ident.clone().into());
586 let self_path = syn::Path { leading_colon: None, segments: self_path_segs};
587 let mut gen_types = GenericTypes::new(Some((types.resolve_path(&self_path, None), &self_path)));
588 assert!(gen_types.learn_generics(&s.generics, types));
590 let mut all_fields_settable = true;
591 for field in fields.named.iter() {
592 if let syn::Visibility::Public(_) = field.vis {
593 let export = export_status(&field.attrs);
595 ExportStatus::Export => {},
596 ExportStatus::NoExport|ExportStatus::TestOnly => {
597 all_fields_settable = false;
602 if let Some(ident) = &field.ident {
603 let ref_type = syn::Type::Reference(syn::TypeReference {
604 and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None,
605 elem: Box::new(field.ty.clone()) });
606 if types.understood_c_type(&ref_type, Some(&gen_types)) {
607 writeln_docs(w, &field.attrs, "");
608 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, ident, struct_name).unwrap();
609 types.write_c_type(w, &ref_type, Some(&gen_types), true);
610 write!(w, " {{\n\tlet mut inner_val = &mut unsafe {{ &mut *this_ptr.inner }}.{};\n\t", ident).unwrap();
611 let local_var = types.write_to_c_conversion_new_var(w, &format_ident!("inner_val"), &ref_type, Some(&gen_types), true);
612 if local_var { write!(w, "\n\t").unwrap(); }
613 types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true);
614 write!(w, "inner_val").unwrap();
615 types.write_to_c_conversion_inline_suffix(w, &ref_type, Some(&gen_types), true);
616 writeln!(w, "\n}}").unwrap();
619 if types.understood_c_type(&field.ty, Some(&gen_types)) {
620 writeln_docs(w, &field.attrs, "");
621 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, ident, struct_name).unwrap();
622 types.write_c_type(w, &field.ty, Some(&gen_types), false);
623 write!(w, ") {{\n\t").unwrap();
624 let local_var = types.write_from_c_conversion_new_var(w, &format_ident!("val"), &field.ty, Some(&gen_types));
625 if local_var { write!(w, "\n\t").unwrap(); }
626 write!(w, "unsafe {{ &mut *this_ptr.inner }}.{} = ", ident).unwrap();
627 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
628 write!(w, "val").unwrap();
629 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
630 writeln!(w, ";\n}}").unwrap();
631 } else { all_fields_settable = false; }
632 } else { all_fields_settable = false; }
633 } else { all_fields_settable = false; }
636 if all_fields_settable {
637 // Build a constructor!
638 writeln!(w, "/// Constructs a new {} given each field", struct_name).unwrap();
639 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_new(", struct_name).unwrap();
640 for (idx, field) in fields.named.iter().enumerate() {
641 if idx != 0 { write!(w, ", ").unwrap(); }
642 write!(w, "mut {}_arg: ", field.ident.as_ref().unwrap()).unwrap();
643 types.write_c_type(w, &field.ty, Some(&gen_types), false);
645 write!(w, ") -> {} {{\n\t", struct_name).unwrap();
646 for field in fields.named.iter() {
647 let field_ident = format_ident!("{}_arg", field.ident.as_ref().unwrap());
648 if types.write_from_c_conversion_new_var(w, &field_ident, &field.ty, Some(&gen_types)) {
649 write!(w, "\n\t").unwrap();
652 writeln!(w, "{} {{ inner: Box::into_raw(Box::new(native{} {{", struct_name, s.ident).unwrap();
653 for field in fields.named.iter() {
654 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
655 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
656 write!(w, "{}_arg", field.ident.as_ref().unwrap()).unwrap();
657 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
658 writeln!(w, ",").unwrap();
660 writeln!(w, "\t}})), is_owned: true }}\n}}").unwrap();
665 /// Prints a relevant conversion for impl *
667 /// For simple impl Struct {}s, this just outputs the wrapper functions as Struct_fn_name() { .. }.
669 /// For impl Trait for Struct{}s, this non-exported generates wrapper functions as
670 /// Trait_Struct_fn_name and a Struct_as_Trait(&struct) -> Trait function which returns a populated
671 /// Trait struct containing a pointer to the passed struct's inner field and the wrapper functions.
673 /// A few non-crate Traits are hard-coded including Default.
674 fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) {
675 match export_status(&i.attrs) {
676 ExportStatus::Export => {},
677 ExportStatus::NoExport|ExportStatus::TestOnly => return,
680 if let syn::Type::Tuple(_) = &*i.self_ty {
681 if types.understood_c_type(&*i.self_ty, None) {
682 let mut gen_types = GenericTypes::new(None);
683 if !gen_types.learn_generics(&i.generics, types) {
684 eprintln!("Not implementing anything for `impl (..)` due to not understood generics");
688 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
689 if let Some(trait_path) = i.trait_.as_ref() {
690 if trait_path.0.is_some() { unimplemented!(); }
691 if types.understood_c_path(&trait_path.1) {
692 eprintln!("Not implementing anything for `impl Trait for (..)` - we only support manual defines");
695 // Just do a manual implementation:
696 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
699 eprintln!("Not implementing anything for plain `impl (..)` block - we only support `impl Trait for (..)` blocks");
705 if let &syn::Type::Path(ref p) = &*i.self_ty {
706 if p.qself.is_some() { unimplemented!(); }
707 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
708 if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) {
709 let mut gen_types = GenericTypes::new(Some((resolved_path.clone(), &p.path)));
710 if !gen_types.learn_generics(&i.generics, types) {
711 eprintln!("Not implementing anything for impl {} due to not understood generics", ident);
715 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
716 if let Some(trait_path) = i.trait_.as_ref() {
717 if trait_path.0.is_some() { unimplemented!(); }
718 if types.understood_c_path(&trait_path.1) {
719 let full_trait_path = types.resolve_path(&trait_path.1, None);
720 let trait_obj = *types.crate_types.traits.get(&full_trait_path).unwrap();
721 // We learn the associated types maping from the original trait object.
722 // That's great, except that they are unresolved idents, so if we learn
723 // mappings from a trai defined in a different file, we may mis-resolve or
724 // fail to resolve the mapped types.
725 gen_types.learn_associated_types(trait_obj, types);
726 let mut impl_associated_types = HashMap::new();
727 for item in i.items.iter() {
729 syn::ImplItem::Type(t) => {
730 if let syn::Type::Path(p) = &t.ty {
731 if let Some(id) = single_ident_generic_path_to_ident(&p.path) {
732 impl_associated_types.insert(&t.ident, id);
740 let export = export_status(&trait_obj.attrs);
742 ExportStatus::Export => {},
743 ExportStatus::NoExport|ExportStatus::TestOnly => return,
746 // For cases where we have a concrete native object which implements a
747 // trait and need to return the C-mapped version of the trait, provide a
748 // From<> implementation which does all the work to ensure free is handled
749 // properly. This way we can call this method from deep in the
750 // type-conversion logic without actually knowing the concrete native type.
751 writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
752 writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();
753 writeln!(w, "\t\tlet mut rust_obj = {} {{ inner: Box::into_raw(Box::new(obj)), is_owned: true }};", ident).unwrap();
754 writeln!(w, "\t\tlet mut ret = {}_as_{}(&rust_obj);", ident, trait_obj.ident).unwrap();
755 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();
756 writeln!(w, "\t\trust_obj.inner = std::ptr::null_mut();").unwrap();
757 writeln!(w, "\t\tret.free = Some({}_free_void);", ident).unwrap();
758 writeln!(w, "\t\tret\n\t}}\n}}").unwrap();
760 writeln!(w, "/// Constructs a new {} which calls the relevant methods on this_arg.", trait_obj.ident).unwrap();
761 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();
762 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: &{}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
763 writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
764 writeln!(w, "\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
765 writeln!(w, "\t\tfree: None,").unwrap();
767 macro_rules! write_meth {
768 ($m: expr, $trait: expr, $indent: expr) => {
769 let trait_method = $trait.items.iter().filter_map(|item| {
770 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
771 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
772 match export_status(&trait_method.attrs) {
773 ExportStatus::Export => {},
774 ExportStatus::NoExport => {
775 write!(w, "{}\t\t//XXX: Need to export {}\n", $indent, $m.sig.ident).unwrap();
778 ExportStatus::TestOnly => continue,
781 let mut printed = false;
782 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
783 if let syn::Type::Reference(r) = &**rtype {
784 write!(w, "\n\t\t{}{}: ", $indent, $m.sig.ident).unwrap();
785 types.write_empty_rust_val(Some(&gen_types), w, &*r.elem);
786 writeln!(w, ",\n{}\t\tset_{}: Some({}_{}_set_{}),", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
791 write!(w, "{}\t\t{}: {}_{}_{},\n", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
795 for item in trait_obj.items.iter() {
797 syn::TraitItem::Method(m) => {
798 write_meth!(m, trait_obj, "");
803 let mut requires_clone = false;
804 walk_supertraits!(trait_obj, Some(&types), (
805 ("Clone", _) => requires_clone = true,
808 walk_supertraits!(trait_obj, Some(&types), (
810 writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap();
812 ("Sync", _) => {}, ("Send", _) => {},
813 ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
815 if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
816 writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();
817 writeln!(w, "\t\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
818 writeln!(w, "\t\t\tfree: None,").unwrap();
819 for item in supertrait_obj.items.iter() {
821 syn::TraitItem::Method(m) => {
822 write_meth!(m, supertrait_obj, "\t");
827 write!(w, "\t\t}},\n").unwrap();
828 if !types.is_clonable(s) && requires_clone {
829 writeln!(w, "\t\t{}_clone: {}_{}_clone,", t, ident, t).unwrap();
832 write_trait_impl_field_assign(w, s, ident);
836 writeln!(w, "\t}}\n}}\n").unwrap();
838 macro_rules! impl_meth {
839 ($m: expr, $trait_path: expr, $trait: expr, $indent: expr) => {
840 let trait_method = $trait.items.iter().filter_map(|item| {
841 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
842 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
843 match export_status(&trait_method.attrs) {
844 ExportStatus::Export => {},
845 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
848 if let syn::ReturnType::Type(_, _) = &$m.sig.output {
849 writeln!(w, "#[must_use]").unwrap();
851 write!(w, "extern \"C\" fn {}_{}_{}(", ident, $trait.ident, $m.sig.ident).unwrap();
852 let mut meth_gen_types = gen_types.push_ctx();
853 assert!(meth_gen_types.learn_generics(&$m.sig.generics, types));
854 write_method_params(w, &$m.sig, "c_void", types, Some(&meth_gen_types), true, true);
855 write!(w, " {{\n\t").unwrap();
856 write_method_var_decl_body(w, &$m.sig, "", types, Some(&meth_gen_types), false);
857 let mut takes_self = false;
858 for inp in $m.sig.inputs.iter() {
859 if let syn::FnArg::Receiver(_) = inp {
864 let mut t_gen_args = String::new();
865 for (idx, _) in $trait.generics.params.iter().enumerate() {
866 if idx != 0 { t_gen_args += ", " };
870 write!(w, "<native{} as {}<{}>>::{}(unsafe {{ &mut *(this_arg as *mut native{}) }}, ", ident, $trait_path, t_gen_args, $m.sig.ident, ident).unwrap();
872 write!(w, "<native{} as {}<{}>>::{}(", ident, $trait_path, t_gen_args, $m.sig.ident).unwrap();
875 let mut real_type = "".to_string();
876 match &$m.sig.output {
877 syn::ReturnType::Type(_, rtype) => {
878 if let Some(mut remaining_path) = first_seg_self(&*rtype) {
879 if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
880 real_type = format!("{}", impl_associated_types.get(associated_seg).unwrap());
886 write_method_call_params(w, &$m.sig, "", types, Some(&meth_gen_types), &real_type, false);
887 write!(w, "\n}}\n").unwrap();
888 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
889 if let syn::Type::Reference(r) = &**rtype {
890 assert_eq!($m.sig.inputs.len(), 1); // Must only take self
891 writeln!(w, "extern \"C\" fn {}_{}_set_{}(trait_self_arg: &{}) {{", ident, $trait.ident, $m.sig.ident, $trait.ident).unwrap();
892 writeln!(w, "\t// This is a bit race-y in the general case, but for our specific use-cases today, we're safe").unwrap();
893 writeln!(w, "\t// Specifically, we must ensure that the first time we're called it can never be in parallel").unwrap();
894 write!(w, "\tif ").unwrap();
895 types.write_empty_rust_val_check(Some(&meth_gen_types), w, &*r.elem, &format!("trait_self_arg.{}", $m.sig.ident));
896 writeln!(w, " {{").unwrap();
897 writeln!(w, "\t\tunsafe {{ &mut *(trait_self_arg as *const {} as *mut {}) }}.{} = {}_{}_{}(trait_self_arg.this_arg);", $trait.ident, $trait.ident, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
898 writeln!(w, "\t}}").unwrap();
899 writeln!(w, "}}").unwrap();
905 for item in i.items.iter() {
907 syn::ImplItem::Method(m) => {
908 impl_meth!(m, full_trait_path, trait_obj, "");
910 syn::ImplItem::Type(_) => {},
911 _ => unimplemented!(),
914 walk_supertraits!(trait_obj, Some(&types), (
916 if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
917 if !types.is_clonable(s) && requires_clone {
918 writeln!(w, "extern \"C\" fn {}_{}_clone(orig: &crate::{}) -> crate::{} {{", ident, t, s, s).unwrap();
919 writeln!(w, "\tcrate::{} {{", s).unwrap();
920 writeln!(w, "\t\tthis_arg: orig.this_arg,").unwrap();
921 writeln!(w, "\t\tfree: None,").unwrap();
922 for item in supertrait_obj.items.iter() {
924 syn::TraitItem::Method(m) => {
925 write_meth!(m, supertrait_obj, "");
930 write!(w, "\t}}\n}}\n").unwrap();
935 write!(w, "\n").unwrap();
936 } else if path_matches_nongeneric(&trait_path.1, &["From"]) {
937 } else if path_matches_nongeneric(&trait_path.1, &["Default"]) {
938 writeln!(w, "/// Creates a \"default\" {}. See struct and individual field documentaiton for details on which values are used.", ident).unwrap();
939 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_default() -> {} {{\n", ident, ident).unwrap();
940 write!(w, "\t{} {{ inner: Box::into_raw(Box::new(Default::default())), is_owned: true }}\n", ident).unwrap();
941 write!(w, "}}\n").unwrap();
942 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "PartialEq"]) {
943 } else if (path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) || path_matches_nongeneric(&trait_path.1, &["Clone"])) &&
944 types.c_type_has_inner_from_path(&resolved_path) {
945 writeln!(w, "impl Clone for {} {{", ident).unwrap();
946 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
947 writeln!(w, "\t\tSelf {{").unwrap();
948 writeln!(w, "\t\t\tinner: if <*mut native{}>::is_null(self.inner) {{ std::ptr::null_mut() }} else {{", ident).unwrap();
949 writeln!(w, "\t\t\t\tBox::into_raw(Box::new(unsafe {{ &*self.inner }}.clone())) }},").unwrap();
950 writeln!(w, "\t\t\tis_owned: true,").unwrap();
951 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
952 writeln!(w, "#[allow(unused)]").unwrap();
953 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
954 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", ident).unwrap();
955 writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", ident).unwrap();
956 writeln!(w, "}}").unwrap();
957 writeln!(w, "#[no_mangle]").unwrap();
958 writeln!(w, "/// Creates a copy of the {}", ident).unwrap();
959 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", ident, ident, ident).unwrap();
960 writeln!(w, "\torig.clone()").unwrap();
961 writeln!(w, "}}").unwrap();
962 } else if path_matches_nongeneric(&trait_path.1, &["FromStr"]) {
963 if let Some(container) = types.get_c_mangled_container_type(
964 vec![&*i.self_ty, &syn::Type::Tuple(syn::TypeTuple { paren_token: Default::default(), elems: syn::punctuated::Punctuated::new() })],
965 Some(&gen_types), "Result") {
966 writeln!(w, "#[no_mangle]").unwrap();
967 writeln!(w, "/// Read a {} object from a string", ident).unwrap();
968 writeln!(w, "pub extern \"C\" fn {}_from_str(s: crate::c_types::Str) -> {} {{", ident, container).unwrap();
969 writeln!(w, "\tmatch {}::from_str(s.into()) {{", resolved_path).unwrap();
970 writeln!(w, "\t\tOk(r) => {{").unwrap();
971 let new_var = types.write_to_c_conversion_new_var(w, &syn::Ident::new("r", Span::call_site()), &*i.self_ty, Some(&gen_types), false);
972 write!(w, "\t\t\tcrate::c_types::CResultTempl::ok(\n\t\t\t\t").unwrap();
973 types.write_to_c_conversion_inline_prefix(w, &*i.self_ty, Some(&gen_types), false);
974 write!(w, "{}r", if new_var { "local_" } else { "" }).unwrap();
975 types.write_to_c_conversion_inline_suffix(w, &*i.self_ty, Some(&gen_types), false);
976 writeln!(w, "\n\t\t\t)\n\t\t}},").unwrap();
977 writeln!(w, "\t\tErr(e) => crate::c_types::CResultTempl::err(0u8),").unwrap();
978 writeln!(w, "\t}}.into()\n}}").unwrap();
980 } else if path_matches_nongeneric(&trait_path.1, &["Display"]) {
981 writeln!(w, "#[no_mangle]").unwrap();
982 writeln!(w, "/// Get the string representation of a {} object", ident).unwrap();
983 writeln!(w, "pub extern \"C\" fn {}_to_str(o: &{}) -> Str {{", ident, resolved_path).unwrap();
984 writeln!(w, "\tformat!(\"{{}}\", o).into()").unwrap();
985 writeln!(w, "}}").unwrap();
987 //XXX: implement for other things like ToString
988 // If we have no generics, try a manual implementation:
989 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
992 let declared_type = (*types.get_declared_type(&ident).unwrap()).clone();
993 for item in i.items.iter() {
995 syn::ImplItem::Method(m) => {
996 if let syn::Visibility::Public(_) = m.vis {
997 match export_status(&m.attrs) {
998 ExportStatus::Export => {},
999 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1001 if m.defaultness.is_some() { unimplemented!(); }
1002 writeln_docs(w, &m.attrs, "");
1003 if let syn::ReturnType::Type(_, _) = &m.sig.output {
1004 writeln!(w, "#[must_use]").unwrap();
1006 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}(", ident, m.sig.ident).unwrap();
1007 let ret_type = match &declared_type {
1008 DeclType::MirroredEnum => format!("{}", ident),
1009 DeclType::StructImported => format!("{}", ident),
1010 _ => unimplemented!(),
1012 let mut meth_gen_types = gen_types.push_ctx();
1013 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
1014 write_method_params(w, &m.sig, &ret_type, types, Some(&meth_gen_types), false, true);
1015 write!(w, " {{\n\t").unwrap();
1016 write_method_var_decl_body(w, &m.sig, "", types, Some(&meth_gen_types), false);
1017 let mut takes_self = false;
1018 let mut takes_mut_self = false;
1019 let mut takes_owned_self = false;
1020 for inp in m.sig.inputs.iter() {
1021 if let syn::FnArg::Receiver(r) = inp {
1023 if r.mutability.is_some() { takes_mut_self = true; }
1024 if r.reference.is_none() { takes_owned_self = true; }
1027 if !takes_mut_self && !takes_self {
1028 write!(w, "{}::{}(", resolved_path, m.sig.ident).unwrap();
1030 match &declared_type {
1031 DeclType::MirroredEnum => write!(w, "this_arg.to_native().{}(", m.sig.ident).unwrap(),
1032 DeclType::StructImported => {
1033 if takes_owned_self {
1034 write!(w, "(*unsafe {{ Box::from_raw(this_arg.take_inner()) }}).{}(", m.sig.ident).unwrap();
1035 } else if takes_mut_self {
1036 write!(w, "unsafe {{ &mut (*(this_arg.inner as *mut native{})) }}.{}(", ident, m.sig.ident).unwrap();
1038 write!(w, "unsafe {{ &*this_arg.inner }}.{}(", m.sig.ident).unwrap();
1041 _ => unimplemented!(),
1044 write_method_call_params(w, &m.sig, "", types, Some(&meth_gen_types), &ret_type, false);
1045 writeln!(w, "\n}}\n").unwrap();
1052 } else if let Some(resolved_path) = types.maybe_resolve_ident(&ident) {
1053 if let Some(aliases) = types.crate_types.reverse_alias_map.get(&resolved_path).cloned() {
1054 'alias_impls: for (alias, arguments) in aliases {
1055 let alias_resolved = types.resolve_path(&alias, None);
1056 for (idx, gen) in i.generics.params.iter().enumerate() {
1058 syn::GenericParam::Type(type_param) => {
1059 'bounds_check: for bound in type_param.bounds.iter() {
1060 if let syn::TypeParamBound::Trait(trait_bound) = bound {
1061 if let syn::PathArguments::AngleBracketed(ref t) = &arguments {
1062 assert!(idx < t.args.len());
1063 if let syn::GenericArgument::Type(syn::Type::Path(p)) = &t.args[idx] {
1064 let generic_arg = types.resolve_path(&p.path, None);
1065 let generic_bound = types.resolve_path(&trait_bound.path, None);
1066 if let Some(traits_impld) = types.crate_types.trait_impls.get(&generic_arg) {
1067 for trait_impld in traits_impld {
1068 if *trait_impld == generic_bound { continue 'bounds_check; }
1070 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1071 continue 'alias_impls;
1073 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1074 continue 'alias_impls;
1076 } else { unimplemented!(); }
1077 } else { unimplemented!(); }
1078 } else { unimplemented!(); }
1081 syn::GenericParam::Lifetime(_) => {},
1082 syn::GenericParam::Const(_) => unimplemented!(),
1085 let aliased_impl = syn::ItemImpl {
1086 attrs: i.attrs.clone(),
1087 brace_token: syn::token::Brace(Span::call_site()),
1089 generics: syn::Generics {
1091 params: syn::punctuated::Punctuated::new(),
1095 impl_token: syn::Token![impl](Span::call_site()),
1096 items: i.items.clone(),
1097 self_ty: Box::new(syn::Type::Path(syn::TypePath { qself: None, path: alias.clone() })),
1098 trait_: i.trait_.clone(),
1101 writeln_impl(w, &aliased_impl, types);
1104 eprintln!("Not implementing anything for {} due to it being marked not exported", ident);
1107 eprintln!("Not implementing anything for {} due to no-resolve (probably the type isn't pub)", ident);
1114 /// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum
1115 /// is unitary), we generate an equivalent enum with all types replaced with their C mapped
1116 /// versions followed by conversion functions which map between the Rust version and the C mapped
1118 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) {
1119 match export_status(&e.attrs) {
1120 ExportStatus::Export => {},
1121 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1124 if is_enum_opaque(e) {
1125 eprintln!("Skipping enum {} as it contains non-unit fields", e.ident);
1126 writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers);
1129 writeln_docs(w, &e.attrs, "");
1131 if e.generics.lt_token.is_some() {
1135 let mut needs_free = false;
1137 writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap();
1138 for var in e.variants.iter() {
1139 assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum
1140 writeln_docs(w, &var.attrs, "\t");
1141 write!(w, "\t{}", var.ident).unwrap();
1142 if let syn::Fields::Named(fields) = &var.fields {
1144 writeln!(w, " {{").unwrap();
1145 for field in fields.named.iter() {
1146 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1147 writeln_docs(w, &field.attrs, "\t\t");
1148 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1149 types.write_c_type(w, &field.ty, None, false);
1150 writeln!(w, ",").unwrap();
1152 write!(w, "\t}}").unwrap();
1153 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1155 write!(w, "(").unwrap();
1156 for (idx, field) in fields.unnamed.iter().enumerate() {
1157 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1158 types.write_c_type(w, &field.ty, None, false);
1159 if idx != fields.unnamed.len() - 1 {
1160 write!(w, ",").unwrap();
1163 write!(w, ")").unwrap();
1165 if var.discriminant.is_some() { unimplemented!(); }
1166 writeln!(w, ",").unwrap();
1168 writeln!(w, "}}\nuse {}::{} as native{};\nimpl {} {{", types.module_path, e.ident, e.ident, e.ident).unwrap();
1170 macro_rules! write_conv {
1171 ($fn_sig: expr, $to_c: expr, $ref: expr) => {
1172 writeln!(w, "\t#[allow(unused)]\n\tpub(crate) fn {} {{\n\t\tmatch {} {{", $fn_sig, if $to_c { "native" } else { "self" }).unwrap();
1173 for var in e.variants.iter() {
1174 write!(w, "\t\t\t{}{}::{} ", if $to_c { "native" } else { "" }, e.ident, var.ident).unwrap();
1175 if let syn::Fields::Named(fields) = &var.fields {
1176 write!(w, "{{").unwrap();
1177 for field in fields.named.iter() {
1178 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1179 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, field.ident.as_ref().unwrap()).unwrap();
1181 write!(w, "}} ").unwrap();
1182 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1183 write!(w, "(").unwrap();
1184 for (idx, field) in fields.unnamed.iter().enumerate() {
1185 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1186 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, ('a' as u8 + idx as u8) as char).unwrap();
1188 write!(w, ") ").unwrap();
1190 write!(w, "=>").unwrap();
1192 macro_rules! handle_field_a {
1193 ($field: expr, $field_ident: expr) => { {
1194 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1195 let mut sink = ::std::io::sink();
1196 let mut out: &mut dyn std::io::Write = if $ref { &mut sink } else { w };
1197 let new_var = if $to_c {
1198 types.write_to_c_conversion_new_var(&mut out, $field_ident, &$field.ty, None, false)
1200 types.write_from_c_conversion_new_var(&mut out, $field_ident, &$field.ty, None)
1202 if $ref || new_var {
1204 write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", $field_ident, $field_ident).unwrap();
1206 let nonref_ident = format_ident!("{}_nonref", $field_ident);
1208 types.write_to_c_conversion_new_var(w, &nonref_ident, &$field.ty, None, false);
1210 types.write_from_c_conversion_new_var(w, &nonref_ident, &$field.ty, None);
1212 write!(w, "\n\t\t\t\t").unwrap();
1215 write!(w, "\n\t\t\t\t").unwrap();
1220 if let syn::Fields::Named(fields) = &var.fields {
1221 write!(w, " {{\n\t\t\t\t").unwrap();
1222 for field in fields.named.iter() {
1223 handle_field_a!(field, field.ident.as_ref().unwrap());
1225 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1226 write!(w, " {{\n\t\t\t\t").unwrap();
1227 for (idx, field) in fields.unnamed.iter().enumerate() {
1228 handle_field_a!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1230 } else { write!(w, " ").unwrap(); }
1232 write!(w, "{}{}::{}", if $to_c { "" } else { "native" }, e.ident, var.ident).unwrap();
1234 macro_rules! handle_field_b {
1235 ($field: expr, $field_ident: expr) => { {
1236 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1238 types.write_to_c_conversion_inline_prefix(w, &$field.ty, None, false);
1240 types.write_from_c_conversion_prefix(w, &$field.ty, None);
1242 write!(w, "{}{}", $field_ident,
1243 if $ref { "_nonref" } else { "" }).unwrap();
1245 types.write_to_c_conversion_inline_suffix(w, &$field.ty, None, false);
1247 types.write_from_c_conversion_suffix(w, &$field.ty, None);
1249 write!(w, ",").unwrap();
1253 if let syn::Fields::Named(fields) = &var.fields {
1254 write!(w, " {{").unwrap();
1255 for field in fields.named.iter() {
1256 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1257 write!(w, "\n\t\t\t\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1258 handle_field_b!(field, field.ident.as_ref().unwrap());
1260 writeln!(w, "\n\t\t\t\t}}").unwrap();
1261 write!(w, "\t\t\t}}").unwrap();
1262 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1263 write!(w, " (").unwrap();
1264 for (idx, field) in fields.unnamed.iter().enumerate() {
1265 write!(w, "\n\t\t\t\t\t").unwrap();
1266 handle_field_b!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1268 writeln!(w, "\n\t\t\t\t)").unwrap();
1269 write!(w, "\t\t\t}}").unwrap();
1271 writeln!(w, ",").unwrap();
1273 writeln!(w, "\t\t}}\n\t}}").unwrap();
1277 write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true);
1278 write_conv!(format!("into_native(self) -> native{}", e.ident), false, false);
1279 write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true);
1280 write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false);
1281 writeln!(w, "}}").unwrap();
1284 writeln!(w, "/// Frees any resources used by the {}", e.ident).unwrap();
1285 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap();
1287 writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap();
1288 writeln!(w, "#[no_mangle]").unwrap();
1289 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap();
1290 writeln!(w, "\torig.clone()").unwrap();
1291 writeln!(w, "}}").unwrap();
1292 write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free);
1295 fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) {
1296 match export_status(&f.attrs) {
1297 ExportStatus::Export => {},
1298 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1300 writeln_docs(w, &f.attrs, "");
1302 let mut gen_types = GenericTypes::new(None);
1303 if !gen_types.learn_generics(&f.sig.generics, types) { return; }
1305 write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap();
1306 write_method_params(w, &f.sig, "", types, Some(&gen_types), false, true);
1307 write!(w, " {{\n\t").unwrap();
1308 write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false);
1309 write!(w, "{}::{}(", types.module_path, f.sig.ident).unwrap();
1310 write_method_call_params(w, &f.sig, "", types, Some(&gen_types), "", false);
1311 writeln!(w, "\n}}\n").unwrap();
1314 // ********************************
1315 // *** File/Crate Walking Logic ***
1316 // ********************************
1318 fn convert_priv_mod<'a, 'b: 'a, W: std::io::Write>(w: &mut W, libast: &'b FullLibraryAST, crate_types: &CrateTypes<'b>, out_dir: &str, mod_path: &str, module: &'b syn::ItemMod) {
1319 // We want to ignore all items declared in this module (as they are not pub), but we still need
1320 // to give the ImportResolver any use statements, so we copy them here.
1321 let mut use_items = Vec::new();
1322 for item in module.content.as_ref().unwrap().1.iter() {
1323 if let syn::Item::Use(_) = item {
1324 use_items.push(item);
1327 let import_resolver = ImportResolver::from_borrowed_items(mod_path.splitn(2, "::").next().unwrap(), &libast.dependencies, mod_path, &use_items);
1328 let mut types = TypeResolver::new(mod_path, import_resolver, crate_types);
1330 writeln!(w, "mod {} {{\n{}", module.ident, DEFAULT_IMPORTS).unwrap();
1331 for item in module.content.as_ref().unwrap().1.iter() {
1333 syn::Item::Mod(m) => convert_priv_mod(w, libast, crate_types, out_dir, &format!("{}::{}", mod_path, module.ident), m),
1334 syn::Item::Impl(i) => {
1335 if let &syn::Type::Path(ref p) = &*i.self_ty {
1336 if p.path.get_ident().is_some() {
1337 writeln_impl(w, i, &mut types);
1344 writeln!(w, "}}").unwrap();
1347 /// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at
1348 /// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST
1349 /// at `module` from C.
1350 fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>, out_dir: &str, header_file: &mut File, cpp_header_file: &mut File) {
1351 for (module, astmod) in libast.modules.iter() {
1352 let orig_crate = module.splitn(2, "::").next().unwrap();
1353 let ASTModule { ref attrs, ref items, ref submods } = astmod;
1354 assert_eq!(export_status(&attrs), ExportStatus::Export);
1356 let new_file_path = if submods.is_empty() {
1357 format!("{}/{}.rs", out_dir, module.replace("::", "/"))
1358 } else if module != "" {
1359 format!("{}/{}/mod.rs", out_dir, module.replace("::", "/"))
1361 format!("{}/lib.rs", out_dir)
1363 let _ = std::fs::create_dir((&new_file_path.as_ref() as &std::path::Path).parent().unwrap());
1364 let mut out = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1365 .open(new_file_path).expect("Unable to open new src file");
1367 writeln!(out, "// This file is Copyright its original authors, visible in version control").unwrap();
1368 writeln!(out, "// history and in the source files from which this was generated.").unwrap();
1369 writeln!(out, "//").unwrap();
1370 writeln!(out, "// This file is licensed under the license available in the LICENSE or LICENSE.md").unwrap();
1371 writeln!(out, "// file in the root of this repository or, if no such file exists, the same").unwrap();
1372 writeln!(out, "// license as that which applies to the original source files from which this").unwrap();
1373 writeln!(out, "// source was automatically generated.").unwrap();
1374 writeln!(out, "").unwrap();
1376 writeln_docs(&mut out, &attrs, "");
1379 // Special-case the top-level lib.rs with various lint allows and a pointer to the c_types
1380 // and bitcoin hand-written modules.
1381 writeln!(out, "//! C Bindings").unwrap();
1382 writeln!(out, "#![allow(unknown_lints)]").unwrap();
1383 writeln!(out, "#![allow(non_camel_case_types)]").unwrap();
1384 writeln!(out, "#![allow(non_snake_case)]").unwrap();
1385 writeln!(out, "#![allow(unused_imports)]").unwrap();
1386 writeln!(out, "#![allow(unused_variables)]").unwrap();
1387 writeln!(out, "#![allow(unused_mut)]").unwrap();
1388 writeln!(out, "#![allow(unused_parens)]").unwrap();
1389 writeln!(out, "#![allow(unused_unsafe)]").unwrap();
1390 writeln!(out, "#![allow(unused_braces)]").unwrap();
1391 // TODO: We need to map deny(missing_docs) in the source crate(s)
1392 //writeln!(out, "#![deny(missing_docs)]").unwrap();
1393 writeln!(out, "pub mod c_types;").unwrap();
1394 writeln!(out, "pub mod bitcoin;").unwrap();
1396 writeln!(out, "{}", DEFAULT_IMPORTS).unwrap();
1400 writeln!(out, "pub mod {};", m).unwrap();
1403 eprintln!("Converting {} entries...", module);
1405 let import_resolver = ImportResolver::new(orig_crate, &libast.dependencies, module, items);
1406 let mut type_resolver = TypeResolver::new(module, import_resolver, crate_types);
1408 for item in items.iter() {
1410 syn::Item::Use(_) => {}, // Handled above
1411 syn::Item::Static(_) => {},
1412 syn::Item::Enum(e) => {
1413 if let syn::Visibility::Public(_) = e.vis {
1414 writeln_enum(&mut out, &e, &mut type_resolver, header_file, cpp_header_file);
1417 syn::Item::Impl(i) => {
1418 writeln_impl(&mut out, &i, &mut type_resolver);
1420 syn::Item::Struct(s) => {
1421 if let syn::Visibility::Public(_) = s.vis {
1422 writeln_struct(&mut out, &s, &mut type_resolver, header_file, cpp_header_file);
1425 syn::Item::Trait(t) => {
1426 if let syn::Visibility::Public(_) = t.vis {
1427 writeln_trait(&mut out, &t, &mut type_resolver, header_file, cpp_header_file);
1430 syn::Item::Mod(m) => {
1431 convert_priv_mod(&mut out, libast, crate_types, out_dir, &format!("{}::{}", module, m.ident), m);
1433 syn::Item::Const(c) => {
1434 // Re-export any primitive-type constants.
1435 if let syn::Visibility::Public(_) = c.vis {
1436 if let syn::Type::Path(p) = &*c.ty {
1437 let resolved_path = type_resolver.resolve_path(&p.path, None);
1438 if type_resolver.is_primitive(&resolved_path) {
1439 writeln_docs(&mut out, &c.attrs, "");
1440 writeln!(out, "\n#[no_mangle]").unwrap();
1441 writeln!(out, "pub static {}: {} = {}::{};", c.ident, resolved_path, module, c.ident).unwrap();
1446 syn::Item::Type(t) => {
1447 if let syn::Visibility::Public(_) = t.vis {
1448 match export_status(&t.attrs) {
1449 ExportStatus::Export => {},
1450 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1453 let mut process_alias = true;
1454 for tok in t.generics.params.iter() {
1455 if let syn::GenericParam::Lifetime(_) = tok {}
1456 else { process_alias = false; }
1460 syn::Type::Path(_) =>
1461 writeln_opaque(&mut out, &t.ident, &format!("{}", t.ident), &t.generics, &t.attrs, &type_resolver, header_file, cpp_header_file),
1467 syn::Item::Fn(f) => {
1468 if let syn::Visibility::Public(_) = f.vis {
1469 writeln_fn(&mut out, &f, &mut type_resolver);
1472 syn::Item::Macro(_) => {},
1473 syn::Item::Verbatim(_) => {},
1474 syn::Item::ExternCrate(_) => {},
1475 _ => unimplemented!(),
1479 out.flush().unwrap();
1483 fn walk_private_mod<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, module: String, items: &'a syn::ItemMod, crate_types: &mut CrateTypes<'a>) {
1484 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, &module, &items.content.as_ref().unwrap().1);
1485 for item in items.content.as_ref().unwrap().1.iter() {
1487 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1488 syn::Item::Impl(i) => {
1489 if let &syn::Type::Path(ref p) = &*i.self_ty {
1490 if let Some(trait_path) = i.trait_.as_ref() {
1491 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1492 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1493 match crate_types.trait_impls.entry(sp) {
1494 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1495 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1507 /// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes.
1508 fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) {
1509 for (module, astmod) in ast_storage.modules.iter() {
1510 let ASTModule { ref attrs, ref items, submods: _ } = astmod;
1511 assert_eq!(export_status(&attrs), ExportStatus::Export);
1512 let orig_crate = module.splitn(2, "::").next().unwrap();
1513 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, module, items);
1515 for item in items.iter() {
1517 syn::Item::Struct(s) => {
1518 if let syn::Visibility::Public(_) = s.vis {
1519 match export_status(&s.attrs) {
1520 ExportStatus::Export => {},
1521 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1523 let struct_path = format!("{}::{}", module, s.ident);
1524 crate_types.opaques.insert(struct_path, &s.ident);
1527 syn::Item::Trait(t) => {
1528 if let syn::Visibility::Public(_) = t.vis {
1529 match export_status(&t.attrs) {
1530 ExportStatus::Export => {},
1531 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1533 let trait_path = format!("{}::{}", module, t.ident);
1534 walk_supertraits!(t, None, (
1536 crate_types.set_clonable("crate::".to_owned() + &trait_path);
1540 crate_types.traits.insert(trait_path, &t);
1543 syn::Item::Type(t) => {
1544 if let syn::Visibility::Public(_) = t.vis {
1545 match export_status(&t.attrs) {
1546 ExportStatus::Export => {},
1547 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1549 let type_path = format!("{}::{}", module, t.ident);
1550 let mut process_alias = true;
1551 for tok in t.generics.params.iter() {
1552 if let syn::GenericParam::Lifetime(_) = tok {}
1553 else { process_alias = false; }
1557 syn::Type::Path(p) => {
1558 let t_ident = &t.ident;
1560 // If its a path with no generics, assume we don't map the aliased type and map it opaque
1561 let path_obj = parse_quote!(#t_ident);
1562 let args_obj = p.path.segments.last().unwrap().arguments.clone();
1563 match crate_types.reverse_alias_map.entry(import_resolver.maybe_resolve_path(&p.path, None).unwrap()) {
1564 hash_map::Entry::Occupied(mut e) => { e.get_mut().push((path_obj, args_obj)); },
1565 hash_map::Entry::Vacant(e) => { e.insert(vec![(path_obj, args_obj)]); },
1568 crate_types.opaques.insert(type_path, t_ident);
1571 crate_types.type_aliases.insert(type_path, import_resolver.resolve_imported_refs((*t.ty).clone()));
1577 syn::Item::Enum(e) if is_enum_opaque(e) => {
1578 if let syn::Visibility::Public(_) = e.vis {
1579 match export_status(&e.attrs) {
1580 ExportStatus::Export => {},
1581 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1583 let enum_path = format!("{}::{}", module, e.ident);
1584 crate_types.opaques.insert(enum_path, &e.ident);
1587 syn::Item::Enum(e) => {
1588 if let syn::Visibility::Public(_) = e.vis {
1589 match export_status(&e.attrs) {
1590 ExportStatus::Export => {},
1591 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1593 let enum_path = format!("{}::{}", module, e.ident);
1594 crate_types.mirrored_enums.insert(enum_path, &e);
1597 syn::Item::Impl(i) => {
1598 if let &syn::Type::Path(ref p) = &*i.self_ty {
1599 if let Some(trait_path) = i.trait_.as_ref() {
1600 if path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) {
1601 if let Some(full_path) = import_resolver.maybe_resolve_path(&p.path, None) {
1602 crate_types.set_clonable("crate::".to_owned() + &full_path);
1605 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1606 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1607 match crate_types.trait_impls.entry(sp) {
1608 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1609 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1616 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1624 let args: Vec<String> = env::args().collect();
1625 if args.len() != 5 {
1626 eprintln!("Usage: target/dir derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
1630 let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1631 .open(&args[2]).expect("Unable to open new header file");
1632 let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1633 .open(&args[3]).expect("Unable to open new header file");
1634 let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1635 .open(&args[4]).expect("Unable to open new header file");
1637 writeln!(header_file, "#if defined(__GNUC__)").unwrap();
1638 writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
1639 writeln!(header_file, "#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
1640 writeln!(header_file, "#else").unwrap();
1641 writeln!(header_file, "#define MUST_USE_STRUCT").unwrap();
1642 writeln!(header_file, "#define MUST_USE_RES").unwrap();
1643 writeln!(header_file, "#endif").unwrap();
1644 writeln!(header_file, "#if defined(__clang__)").unwrap();
1645 writeln!(header_file, "#define NONNULL_PTR _Nonnull").unwrap();
1646 writeln!(header_file, "#else").unwrap();
1647 writeln!(header_file, "#define NONNULL_PTR").unwrap();
1648 writeln!(header_file, "#endif").unwrap();
1649 writeln!(cpp_header_file, "#include <string.h>\nnamespace LDK {{").unwrap();
1651 // First parse the full crate's ASTs, caching them so that we can hold references to the AST
1652 // objects in other datastructures:
1653 let mut lib_src = String::new();
1654 std::io::stdin().lock().read_to_string(&mut lib_src).unwrap();
1655 let lib_syntax = syn::parse_file(&lib_src).expect("Unable to parse file");
1656 let libast = FullLibraryAST::load_lib(lib_syntax);
1658 // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
1659 // when parsing other file ASTs...
1660 let mut libtypes = CrateTypes::new(&mut derived_templates, &libast);
1661 walk_ast(&libast, &mut libtypes);
1663 // ... finally, do the actual file conversion/mapping, writing out types as we go.
1664 convert_file(&libast, &libtypes, &args[1], &mut header_file, &mut cpp_header_file);
1666 // For container templates which we created while walking the crate, make sure we add C++
1667 // mapped types so that C++ users can utilize the auto-destructors available.
1668 for (ty, has_destructor) in libtypes.templates_defined.borrow().iter() {
1669 write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor);
1671 writeln!(cpp_header_file, "}}").unwrap();
1673 header_file.flush().unwrap();
1674 cpp_header_file.flush().unwrap();
1675 derived_templates.flush().unwrap();