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 core::convert::Infallible;\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"|"lightning::util::ser::MaybeReadable" => {
88 // Create the Result<Object, DecodeError> syn::Type
89 let mut 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!(); }
114 } else if t == "lightning::util::ser::MaybeReadable" {
115 res_ty = parse_quote!(Result<Option<#for_ty>, ::ln::msgs::DecodeError>);
117 write!(w, ") -> ").unwrap();
118 types.write_c_type(w, &res_ty, Some(generics), false);
119 writeln!(w, " {{").unwrap();
121 if t == "lightning::util::ser::ReadableArgs" {
122 w.write(&arg_conv).unwrap();
123 write!(w, ";\n").unwrap();
126 write!(w, "\tlet res: ").unwrap();
127 // At least in one case we need type annotations here, so provide them.
128 types.write_rust_type(w, Some(generics), &res_ty);
130 if t == "lightning::util::ser::ReadableArgs" {
131 writeln!(w, " = crate::c_types::deserialize_obj_arg(ser, arg_conv);").unwrap();
132 } else if t == "lightning::util::ser::MaybeReadable" {
133 writeln!(w, " = crate::c_types::maybe_deserialize_obj(ser);").unwrap();
135 writeln!(w, " = crate::c_types::deserialize_obj(ser);").unwrap();
137 write!(w, "\t").unwrap();
138 if types.write_to_c_conversion_new_var(w, &format_ident!("res"), &res_ty, Some(generics), false) {
139 write!(w, "\n\t").unwrap();
141 types.write_to_c_conversion_inline_prefix(w, &res_ty, Some(generics), false);
142 write!(w, "res").unwrap();
143 types.write_to_c_conversion_inline_suffix(w, &res_ty, Some(generics), false);
144 writeln!(w, "\n}}").unwrap();
151 /// Convert "TraitA : TraitB" to a single function name and return type.
153 /// This is (obviously) somewhat over-specialized and only useful for TraitB's that only require a
154 /// single function (eg for serialization).
155 fn convert_trait_impl_field(trait_path: &str) -> (&'static str, String, &'static str) {
157 "lightning::util::ser::Writeable" => ("Serialize the object into a byte array", "write".to_owned(), "crate::c_types::derived::CVec_u8Z"),
158 _ => unimplemented!(),
162 /// Companion to convert_trait_impl_field, write an assignment for the function defined by it for
163 /// `for_obj` which implements the the trait at `trait_path`.
164 fn write_trait_impl_field_assign<W: std::io::Write>(w: &mut W, trait_path: &str, for_obj: &syn::Ident) {
166 "lightning::util::ser::Writeable" => {
167 writeln!(w, "\t\twrite: {}_write_void,", for_obj).unwrap();
169 _ => unimplemented!(),
173 /// Write out the impl block for a defined trait struct which has a supertrait
174 fn do_write_impl_trait<W: std::io::Write>(w: &mut W, trait_path: &str, _trait_name: &syn::Ident, for_obj: &str) {
176 "lightning::util::ser::Writeable" => {
177 writeln!(w, "impl {} for {} {{", trait_path, for_obj).unwrap();
178 writeln!(w, "\tfn write<W: lightning::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {{").unwrap();
179 writeln!(w, "\t\tlet vec = (self.write)(self.this_arg);").unwrap();
180 writeln!(w, "\t\tw.write_all(vec.as_slice())").unwrap();
181 writeln!(w, "\t}}\n}}").unwrap();
187 /// Returns true if an instance of the given type must never exist
188 fn is_type_unconstructable(path: &str) -> bool {
189 path == "core::convert::Infallible" || path == "crate::c_types::NotConstructable"
192 // *******************************
193 // *** Per-Type Printing Logic ***
194 // *******************************
196 macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $($pat: pat)|* => $e: expr),*) ) => { {
197 if $t.colon_token.is_some() {
198 for st in $t.supertraits.iter() {
200 syn::TypeParamBound::Trait(supertrait) => {
201 if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() {
204 // First try to resolve path to find in-crate traits, but if that doesn't work
205 // assume its a prelude trait (eg Clone, etc) and just use the single ident.
206 let types_opt: Option<&TypeResolver> = $types;
207 if let Some(types) = types_opt {
208 if let Some(path) = types.maybe_resolve_path(&supertrait.path, None) {
209 match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
210 $( $($pat)|* => $e, )*
215 if let Some(ident) = supertrait.path.get_ident() {
216 match (&format!("{}", ident) as &str, &ident) {
217 $( $($pat)|* => $e, )*
219 } else if types_opt.is_some() {
220 panic!("Supertrait unresolvable and not single-ident");
223 syn::TypeParamBound::Lifetime(_) => unimplemented!(),
229 macro_rules! get_module_type_resolver {
230 ($module: expr, $crate_libs: expr, $crate_types: expr) => { {
231 let module: &str = &$module;
232 let mut module_iter = module.rsplitn(2, "::");
233 module_iter.next().unwrap();
234 let module = module_iter.next().unwrap();
235 let imports = ImportResolver::new(module.splitn(2, "::").next().unwrap(), &$crate_types.lib_ast.dependencies,
236 module, &$crate_types.lib_ast.modules.get(module).unwrap().items);
237 TypeResolver::new(module, imports, $crate_types)
241 /// Prints a C-mapped trait object containing a void pointer and a jump table for each function in
242 /// the original trait.
243 /// Implements the native Rust trait and relevant parent traits for the new C-mapped trait.
245 /// Finally, implements Deref<MappedTrait> for MappedTrait which allows its use in types which need
246 /// a concrete Deref to the Rust trait.
247 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) {
248 let trait_name = format!("{}", t.ident);
250 match export_status(&t.attrs) {
251 ExportStatus::Export => { implementable = true; }
252 ExportStatus::NotImplementable => { implementable = false; },
253 ExportStatus::NoExport|ExportStatus::TestOnly => return,
255 writeln_docs(w, &t.attrs, "");
257 let mut gen_types = GenericTypes::new(None);
259 // Add functions which may be required for supertrait implementations.
260 // Due to borrow checker limitations, we only support one in-crate supertrait here.
262 let supertrait_resolver;
263 walk_supertraits!(t, Some(&types), (
265 if let Some(supertrait) = types.crate_types.traits.get(s) {
266 supertrait_name = s.to_string();
267 supertrait_resolver = get_module_type_resolver!(supertrait_name, types.crate_libs, types.crate_types);
268 gen_types.learn_associated_types(&supertrait, &supertrait_resolver);
274 assert!(gen_types.learn_generics(&t.generics, types));
275 gen_types.learn_associated_types(&t, types);
277 writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap();
278 writeln!(w, "\t/// An opaque pointer which is passed to your function implementations as an argument.").unwrap();
279 writeln!(w, "\t/// This has no meaning in the LDK, and can be NULL or any other value.").unwrap();
280 writeln!(w, "\tpub this_arg: *mut c_void,").unwrap();
281 // We store every field's (name, Option<clone_fn>, docs) except this_arg, used in Clone generation
282 // docs is only set if its a function which should be callable on the object itself in C++
283 let mut generated_fields = Vec::new();
284 for item in t.items.iter() {
286 &syn::TraitItem::Method(ref m) => {
287 match export_status(&m.attrs) {
288 ExportStatus::NoExport => {
289 // NoExport in this context means we'll hit an unimplemented!() at runtime,
293 ExportStatus::Export => {},
294 ExportStatus::TestOnly => continue,
295 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
297 if m.default.is_some() { unimplemented!(); }
299 let mut meth_gen_types = gen_types.push_ctx();
300 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
302 writeln_fn_docs(w, &m.attrs, "\t", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
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), None, None));
318 types.write_c_type(w, &*r.elem, Some(&meth_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), None, None));
325 // Note that cbindgen will now generate
326 // typedef struct Thing {..., set_thing: (const struct 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();
331 // Sadly, this currently doesn't do what we want, but it should be easy to get
332 // cbindgen to support it. See https://github.com/eqrion/cbindgen/issues/531
333 writeln!(w, "\t#[must_use]").unwrap();
336 let mut cpp_docs = Vec::new();
337 writeln_fn_docs(&mut cpp_docs, &m.attrs, "\t * ", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
338 let docs_string = "\t/**\n".to_owned() + &String::from_utf8(cpp_docs).unwrap().replace("///", "") + "\t */\n";
340 write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap();
341 generated_fields.push((format!("{}", m.sig.ident), None, Some(docs_string)));
342 write_method_params(w, &m.sig, "c_void", types, Some(&meth_gen_types), true, false);
343 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/// Called, if set, after this {} has been cloned into a duplicate object.", trait_name).unwrap();
353 writeln!(w, "\t/// The new {} is provided, and should be mutated as needed to perform a", trait_name).unwrap();
354 writeln!(w, "\t/// deep copy of the object pointed to by this_arg or avoid any double-freeing.").unwrap();
355 writeln!(w, "\tpub cloned: Option<extern \"C\" fn (new_{}: &mut {})>,", trait_name, trait_name).unwrap();
356 generated_fields.push(("cloned".to_owned(), None, None));
358 ("std::cmp::Eq", _)|("core::cmp::Eq", _) => {
359 let eq_docs = "Checks if two objects are equal given this object's this_arg pointer and another object.";
360 writeln!(w, "\t/// {}", eq_docs).unwrap();
361 writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap();
362 generated_fields.push(("eq".to_owned(), None, Some(format!("\t/** {} */\n", eq_docs))));
364 ("std::hash::Hash", _)|("core::hash::Hash", _) => {
365 let hash_docs_a = "Calculate a succinct non-cryptographic hash for an object given its this_arg pointer.";
366 let hash_docs_b = "This is used, for example, for inclusion of this object in a hash map.";
367 writeln!(w, "\t/// {}", hash_docs_a).unwrap();
368 writeln!(w, "\t/// {}", hash_docs_b).unwrap();
369 writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap();
370 generated_fields.push(("hash".to_owned(), None,
371 Some(format!("\t/**\n\t * {}\n\t * {}\n\t */\n", hash_docs_a, hash_docs_b))));
373 ("Send", _) => {}, ("Sync", _) => {},
374 ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
375 let debug_docs = "Return a human-readable \"debug\" string describing this object";
376 writeln!(w, "\t/// {}", debug_docs).unwrap();
377 writeln!(w, "\tpub debug_str: extern \"C\" fn (this_arg: *const c_void) -> crate::c_types::Str,").unwrap();
378 generated_fields.push(("debug_str".to_owned(), None,
379 Some(format!("\t/**\n\t * {}\n\t */\n", debug_docs))));
382 // TODO: Both of the below should expose supertrait methods in C++, but doing so is
384 generated_fields.push(if types.crate_types.traits.get(s).is_none() {
385 let (docs, name, ret) = convert_trait_impl_field(s);
386 writeln!(w, "\t/// {}", docs).unwrap();
387 writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap();
388 (name, None, None) // Assume clonable
390 // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
391 writeln!(w, "\t/// Implementation of {} for this object.", i).unwrap();
392 let is_clonable = types.is_clonable(s);
393 writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
394 (format!("{}", i), if !is_clonable {
395 Some(format!("crate::{}_clone_fields", s))
396 } else { None }, None)
400 writeln!(w, "\t/// Frees any resources associated with this object given its this_arg pointer.").unwrap();
401 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();
402 writeln!(w, "\tpub free: Option<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
403 generated_fields.push(("free".to_owned(), None, None));
404 writeln!(w, "}}").unwrap();
406 macro_rules! impl_trait_for_c {
407 ($t: expr, $impl_accessor: expr, $type_resolver: expr) => {
408 for item in $t.items.iter() {
410 syn::TraitItem::Method(m) => {
411 if let ExportStatus::TestOnly = export_status(&m.attrs) { continue; }
412 if m.default.is_some() { unimplemented!(); }
413 if m.sig.constness.is_some() || m.sig.asyncness.is_some() || m.sig.unsafety.is_some() ||
414 m.sig.abi.is_some() || m.sig.variadic.is_some() {
417 let mut meth_gen_types = gen_types.push_ctx();
418 assert!(meth_gen_types.learn_generics(&m.sig.generics, $type_resolver));
419 // Note that we do *not* use the method generics when printing "native"
420 // rust parts - if the method is generic, we need to print a generic
422 write!(w, "\tfn {}", m.sig.ident).unwrap();
423 $type_resolver.write_rust_generic_param(w, Some(&gen_types), m.sig.generics.params.iter());
424 write!(w, "(").unwrap();
425 for inp in m.sig.inputs.iter() {
427 syn::FnArg::Receiver(recv) => {
428 if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
429 write!(w, "&").unwrap();
430 if let Some(lft) = &recv.reference.as_ref().unwrap().1 {
431 write!(w, "'{} ", lft.ident).unwrap();
433 if recv.mutability.is_some() {
434 write!(w, "mut self").unwrap();
436 write!(w, "self").unwrap();
439 syn::FnArg::Typed(arg) => {
440 if !arg.attrs.is_empty() { unimplemented!(); }
442 syn::Pat::Ident(ident) => {
443 if !ident.attrs.is_empty() || ident.by_ref.is_some() ||
444 ident.mutability.is_some() || ident.subpat.is_some() {
447 write!(w, ", mut {}{}: ", if $type_resolver.skip_arg(&*arg.ty, Some(&meth_gen_types)) { "_" } else { "" }, ident.ident).unwrap();
449 _ => unimplemented!(),
451 $type_resolver.write_rust_type(w, Some(&gen_types), &*arg.ty);
455 write!(w, ")").unwrap();
456 match &m.sig.output {
457 syn::ReturnType::Type(_, rtype) => {
458 write!(w, " -> ").unwrap();
459 $type_resolver.write_rust_type(w, Some(&gen_types), &*rtype)
463 write!(w, " {{\n\t\t").unwrap();
464 match export_status(&m.attrs) {
465 ExportStatus::NoExport => {
470 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
471 if let syn::Type::Reference(r) = &**rtype {
472 assert_eq!(m.sig.inputs.len(), 1); // Must only take self!
473 writeln!(w, "if let Some(f) = self{}.set_{} {{", $impl_accessor, m.sig.ident).unwrap();
474 writeln!(w, "\t\t\t(f)(&self{});", $impl_accessor).unwrap();
475 write!(w, "\t\t}}\n\t\t").unwrap();
476 $type_resolver.write_from_c_conversion_to_ref_prefix(w, &*r.elem, Some(&meth_gen_types));
477 write!(w, "self{}.{}", $impl_accessor, m.sig.ident).unwrap();
478 $type_resolver.write_from_c_conversion_to_ref_suffix(w, &*r.elem, Some(&meth_gen_types));
479 writeln!(w, "\n\t}}").unwrap();
483 write_method_var_decl_body(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), true);
484 write!(w, "(self{}.{})(", $impl_accessor, m.sig.ident).unwrap();
485 let mut args = Vec::new();
486 write_method_call_params(&mut args, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), "", true);
487 w.write_all(String::from_utf8(args).unwrap().replace("self", &format!("self{}", $impl_accessor)).as_bytes()).unwrap();
489 writeln!(w, "\n\t}}").unwrap();
491 &syn::TraitItem::Type(ref t) => {
492 if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); }
493 let mut bounds_iter = t.bounds.iter();
495 match bounds_iter.next().unwrap() {
496 syn::TypeParamBound::Trait(tr) => {
497 writeln!(w, "\ttype {} = crate::{};", t.ident, $type_resolver.resolve_path(&tr.path, Some(&gen_types))).unwrap();
498 for bound in bounds_iter {
499 if let syn::TypeParamBound::Trait(_) = bound { unimplemented!(); }
503 syn::TypeParamBound::Lifetime(_) => {},
507 _ => unimplemented!(),
513 writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap();
514 writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap();
516 writeln!(w, "#[no_mangle]").unwrap();
517 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_fields(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
518 writeln!(w, "\t{} {{", trait_name).unwrap();
519 writeln!(w, "\t\tthis_arg: orig.this_arg,").unwrap();
520 for (field, clone_fn, _) in generated_fields.iter() {
521 if let Some(f) = clone_fn {
522 // If the field isn't clonable, blindly assume its a trait and hope for the best.
523 writeln!(w, "\t\t{}: {}(&orig.{}),", field, f, field).unwrap();
525 writeln!(w, "\t\t{}: Clone::clone(&orig.{}),", field, field).unwrap();
528 writeln!(w, "\t}}\n}}").unwrap();
530 // Implement supertraits for the C-mapped struct.
531 walk_supertraits!(t, Some(&types), (
532 ("std::cmp::Eq", _)|("core::cmp::Eq", _) => {
533 writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap();
534 writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap();
535 writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o) }}\n}}").unwrap();
537 ("std::hash::Hash", _)|("core::hash::Hash", _) => {
538 writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap();
539 writeln!(w, "\tfn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap();
541 ("Send", _) => {}, ("Sync", _) => {},
543 writeln!(w, "#[no_mangle]").unwrap();
544 writeln!(w, "/// Creates a copy of a {}", trait_name).unwrap();
545 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
546 writeln!(w, "\tlet mut res = {}_clone_fields(orig);", trait_name).unwrap();
547 writeln!(w, "\tif let Some(f) = orig.cloned {{ (f)(&mut res) }};").unwrap();
548 writeln!(w, "\tres\n}}").unwrap();
549 writeln!(w, "impl Clone for {} {{", trait_name).unwrap();
550 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
551 writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap();
552 writeln!(w, "\t}}\n}}").unwrap();
554 ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
555 writeln!(w, "impl core::fmt::Debug for {} {{", trait_name).unwrap();
556 writeln!(w, "\tfn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {{").unwrap();
557 writeln!(w, "\t\tf.write_str((self.debug_str)(self.this_arg).into_str())").unwrap();
558 writeln!(w, "\t}}").unwrap();
559 writeln!(w, "}}").unwrap();
562 if let Some(supertrait) = types.crate_types.traits.get(s) {
563 let resolver = get_module_type_resolver!(s, types.crate_libs, types.crate_types);
564 writeln!(w, "impl {} for {} {{", s, trait_name).unwrap();
565 impl_trait_for_c!(supertrait, format!(".{}", i), &resolver);
566 writeln!(w, "}}").unwrap();
568 do_write_impl_trait(w, s, i, &trait_name);
573 // Finally, implement the original Rust trait for the newly created mapped trait.
574 writeln!(w, "\nuse {}::{} as rust{};", types.module_path, t.ident, trait_name).unwrap();
576 write!(w, "impl").unwrap();
577 maybe_write_lifetime_generics(w, &t.generics, types);
578 write!(w, " rust{}", t.ident).unwrap();
579 maybe_write_generics(w, &t.generics, types, false);
580 writeln!(w, " for {} {{", trait_name).unwrap();
581 impl_trait_for_c!(t, "", types);
582 writeln!(w, "}}\n").unwrap();
583 writeln!(w, "// We're essentially a pointer already, or at least a set of pointers, so allow us to be used").unwrap();
584 writeln!(w, "// directly as a Deref trait in higher-level structs:").unwrap();
585 writeln!(w, "impl std::ops::Deref for {} {{\n\ttype Target = Self;", trait_name).unwrap();
586 writeln!(w, "\tfn deref(&self) -> &Self {{\n\t\tself\n\t}}\n}}").unwrap();
589 writeln!(w, "/// Calls the free function if one is set").unwrap();
590 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", trait_name, trait_name).unwrap();
591 writeln!(w, "impl Drop for {} {{", trait_name).unwrap();
592 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
593 writeln!(w, "\t\tif let Some(f) = self.free {{").unwrap();
594 writeln!(w, "\t\t\tf(self.this_arg);").unwrap();
595 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
597 write_cpp_wrapper(cpp_headers, &trait_name, true, Some(generated_fields.drain(..)
598 .filter_map(|(name, _, docs)| if let Some(docs) = docs { Some((name, docs)) } else { None }).collect()));
601 /// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type
602 /// and a flag to indicate whether Drop'ing the mapped struct drops the underlying Rust type.
604 /// Also writes out a _free function and a C++ wrapper which handles calling _free.
605 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) {
606 // If we directly read the original type by its original name, cbindgen hits
607 // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary
608 // name and then reference it by that name, which works around the issue.
609 write!(w, "\nuse {}::{} as native{}Import;\npub(crate) type native{} = native{}Import", types.module_path, ident, ident, ident, ident).unwrap();
610 maybe_write_generics(w, &generics, &types, true);
611 writeln!(w, ";\n").unwrap();
612 writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap();
613 writeln_docs(w, &attrs, "");
614 writeln!(w, "#[must_use]\n#[repr(C)]\npub struct {} {{", struct_name).unwrap();
615 writeln!(w, "\t/// A pointer to the opaque Rust object.\n").unwrap();
616 writeln!(w, "\t/// Nearly everywhere, inner must be non-null, however in places where").unwrap();
617 writeln!(w, "\t/// the Rust equivalent takes an Option, it may be set to null to indicate None.").unwrap();
618 writeln!(w, "\tpub inner: *mut native{},", ident).unwrap();
619 writeln!(w, "\t/// Indicates that this is the only struct which contains the same pointer.\n").unwrap();
620 writeln!(w, "\t/// Rust functions which take ownership of an object provided via an argument require").unwrap();
621 writeln!(w, "\t/// this to be true and invalidate the object pointed to by inner.").unwrap();
622 writeln!(w, "\tpub is_owned: bool,").unwrap();
623 writeln!(w, "}}\n").unwrap();
624 writeln!(w, "impl Drop for {} {{\n\tfn drop(&mut self) {{", struct_name).unwrap();
625 writeln!(w, "\t\tif self.is_owned && !<*mut native{}>::is_null(self.inner) {{", ident).unwrap();
626 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(ObjOps::untweak_ptr(self.inner)) }};\n\t\t}}\n\t}}\n}}").unwrap();
627 writeln!(w, "/// Frees any resources used by the {}, if is_owned is set and inner is non-NULL.", struct_name).unwrap();
628 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_obj: {}) {{ }}", struct_name, struct_name).unwrap();
629 writeln!(w, "#[allow(unused)]").unwrap();
630 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
631 writeln!(w, "pub(crate) extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
632 writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap();
633 writeln!(w, "#[allow(unused)]").unwrap();
634 writeln!(w, "impl {} {{", struct_name).unwrap();
635 writeln!(w, "\tpub(crate) fn get_native_ref(&self) -> &'static native{} {{", struct_name).unwrap();
636 writeln!(w, "\t\tunsafe {{ &*ObjOps::untweak_ptr(self.inner) }}").unwrap();
637 writeln!(w, "\t}}").unwrap();
638 writeln!(w, "\tpub(crate) fn get_native_mut_ref(&self) -> &'static mut native{} {{", struct_name).unwrap();
639 writeln!(w, "\t\tunsafe {{ &mut *ObjOps::untweak_ptr(self.inner) }}").unwrap();
640 writeln!(w, "\t}}").unwrap();
641 writeln!(w, "\t/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap();
642 writeln!(w, "\tpub(crate) fn take_inner(mut self) -> *mut native{} {{", struct_name).unwrap();
643 writeln!(w, "\t\tassert!(self.is_owned);").unwrap();
644 writeln!(w, "\t\tlet ret = ObjOps::untweak_ptr(self.inner);").unwrap();
645 writeln!(w, "\t\tself.inner = std::ptr::null_mut();").unwrap();
646 writeln!(w, "\t\tret").unwrap();
647 writeln!(w, "\t}}\n}}").unwrap();
649 write_cpp_wrapper(cpp_headers, &format!("{}", ident), true, None);
652 /// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
653 /// the struct itself, and then writing getters and setters for public, understood-type fields and
654 /// a constructor if every field is public.
655 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) {
656 if export_status(&s.attrs) != ExportStatus::Export { return; }
658 let struct_name = &format!("{}", s.ident);
659 writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers);
661 let mut self_path_segs = syn::punctuated::Punctuated::new();
662 self_path_segs.push(s.ident.clone().into());
663 let self_path = syn::Path { leading_colon: None, segments: self_path_segs};
664 let mut gen_types = GenericTypes::new(Some(types.resolve_path(&self_path, None)));
665 assert!(gen_types.learn_generics(&s.generics, types));
667 let mut all_fields_settable = true;
668 macro_rules! define_field {
669 ($new_name: expr, $real_name: expr, $field: expr) => {
670 if let syn::Visibility::Public(_) = $field.vis {
671 let export = export_status(&$field.attrs);
673 ExportStatus::Export => {},
674 ExportStatus::NoExport|ExportStatus::TestOnly => {
675 all_fields_settable = false;
678 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
681 if let Some(ref_type) = types.create_ownable_reference(&$field.ty, Some(&gen_types)) {
682 if types.understood_c_type(&ref_type, Some(&gen_types)) {
683 writeln_arg_docs(w, &$field.attrs, "", types, Some(&gen_types), vec![].drain(..), Some(&ref_type));
684 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, $new_name, struct_name).unwrap();
685 types.write_c_type(w, &ref_type, Some(&gen_types), true);
686 write!(w, " {{\n\tlet mut inner_val = &mut this_ptr.get_native_mut_ref().{};\n\t", $real_name).unwrap();
687 let local_var = types.write_to_c_conversion_from_ownable_ref_new_var(w, &format_ident!("inner_val"), &ref_type, Some(&gen_types));
688 if local_var { write!(w, "\n\t").unwrap(); }
689 types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true);
690 write!(w, "inner_val").unwrap();
691 types.write_to_c_conversion_inline_suffix(w, &ref_type, Some(&gen_types), true);
692 writeln!(w, "\n}}").unwrap();
696 if types.understood_c_type(&$field.ty, Some(&gen_types)) {
697 writeln_arg_docs(w, &$field.attrs, "", types, Some(&gen_types), vec![("val".to_owned(), &$field.ty)].drain(..), None);
698 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, $new_name, struct_name).unwrap();
699 types.write_c_type(w, &$field.ty, Some(&gen_types), false);
700 write!(w, ") {{\n\t").unwrap();
701 let local_var = types.write_from_c_conversion_new_var(w, &format_ident!("val"), &$field.ty, Some(&gen_types));
702 if local_var { write!(w, "\n\t").unwrap(); }
703 write!(w, "unsafe {{ &mut *ObjOps::untweak_ptr(this_ptr.inner) }}.{} = ", $real_name).unwrap();
704 types.write_from_c_conversion_prefix(w, &$field.ty, Some(&gen_types));
705 write!(w, "val").unwrap();
706 types.write_from_c_conversion_suffix(w, &$field.ty, Some(&gen_types));
707 writeln!(w, ";\n}}").unwrap();
708 } else { all_fields_settable = false; }
709 } else { all_fields_settable = false; }
714 syn::Fields::Named(fields) => {
715 for field in fields.named.iter() {
716 if let Some(ident) = &field.ident {
717 define_field!(ident, ident, field);
718 } else { all_fields_settable = false; }
721 syn::Fields::Unnamed(fields) => {
722 for (idx, field) in fields.unnamed.iter().enumerate() {
723 define_field!(('a' as u8 + idx as u8) as char, ('0' as u8 + idx as u8) as char, field);
726 _ => unimplemented!()
729 if all_fields_settable {
730 // Build a constructor!
731 writeln!(w, "/// Constructs a new {} given each field", struct_name).unwrap();
732 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_new(", struct_name).unwrap();
735 syn::Fields::Named(fields) => {
736 for (idx, field) in fields.named.iter().enumerate() {
737 if idx != 0 { write!(w, ", ").unwrap(); }
738 write!(w, "mut {}_arg: ", field.ident.as_ref().unwrap()).unwrap();
739 types.write_c_type(w, &field.ty, Some(&gen_types), false);
742 syn::Fields::Unnamed(fields) => {
743 for (idx, field) in fields.unnamed.iter().enumerate() {
744 if idx != 0 { write!(w, ", ").unwrap(); }
745 write!(w, "mut {}_arg: ", ('a' as u8 + idx as u8) as char).unwrap();
746 types.write_c_type(w, &field.ty, Some(&gen_types), false);
751 write!(w, ") -> {} {{\n\t", struct_name).unwrap();
753 syn::Fields::Named(fields) => {
754 for field in fields.named.iter() {
755 let field_ident = format_ident!("{}_arg", field.ident.as_ref().unwrap());
756 if types.write_from_c_conversion_new_var(w, &field_ident, &field.ty, Some(&gen_types)) {
757 write!(w, "\n\t").unwrap();
761 syn::Fields::Unnamed(fields) => {
762 for (idx, field) in fields.unnamed.iter().enumerate() {
763 let field_ident = format_ident!("{}_arg", ('a' as u8 + idx as u8) as char);
764 if types.write_from_c_conversion_new_var(w, &field_ident, &field.ty, Some(&gen_types)) {
765 write!(w, "\n\t").unwrap();
771 write!(w, "{} {{ inner: ObjOps::heap_alloc(", struct_name).unwrap();
773 syn::Fields::Named(fields) => {
774 writeln!(w, "native{} {{", s.ident).unwrap();
775 for field in fields.named.iter() {
776 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
777 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
778 write!(w, "{}_arg", field.ident.as_ref().unwrap()).unwrap();
779 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
780 writeln!(w, ",").unwrap();
782 write!(w, "\t}}").unwrap();
784 syn::Fields::Unnamed(fields) => {
785 assert!(s.generics.lt_token.is_none());
786 writeln!(w, "{} (", types.maybe_resolve_ident(&s.ident).unwrap()).unwrap();
787 for (idx, field) in fields.unnamed.iter().enumerate() {
788 write!(w, "\t\t").unwrap();
789 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
790 write!(w, "{}_arg", ('a' as u8 + idx as u8) as char).unwrap();
791 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
792 writeln!(w, ",").unwrap();
794 write!(w, "\t)").unwrap();
798 writeln!(w, "), is_owned: true }}\n}}").unwrap();
802 /// Prints a relevant conversion for impl *
804 /// For simple impl Struct {}s, this just outputs the wrapper functions as Struct_fn_name() { .. }.
806 /// For impl Trait for Struct{}s, this non-exported generates wrapper functions as
807 /// Trait_Struct_fn_name and a Struct_as_Trait(&struct) -> Trait function which returns a populated
808 /// Trait struct containing a pointer to the passed struct's inner field and the wrapper functions.
810 /// A few non-crate Traits are hard-coded including Default.
811 fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) {
812 match export_status(&i.attrs) {
813 ExportStatus::Export => {},
814 ExportStatus::NoExport|ExportStatus::TestOnly => return,
815 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
818 if let syn::Type::Tuple(_) = &*i.self_ty {
819 if types.understood_c_type(&*i.self_ty, None) {
820 let mut gen_types = GenericTypes::new(None);
821 if !gen_types.learn_generics(&i.generics, types) {
822 eprintln!("Not implementing anything for `impl (..)` due to not understood generics");
826 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
827 if let Some(trait_path) = i.trait_.as_ref() {
828 if trait_path.0.is_some() { unimplemented!(); }
829 if types.understood_c_path(&trait_path.1) {
830 eprintln!("Not implementing anything for `impl Trait for (..)` - we only support manual defines");
833 // Just do a manual implementation:
834 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
837 eprintln!("Not implementing anything for plain `impl (..)` block - we only support `impl Trait for (..)` blocks");
843 if let &syn::Type::Path(ref p) = &*i.self_ty {
844 if p.qself.is_some() { unimplemented!(); }
845 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
846 if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) {
847 if !types.understood_c_path(&p.path) {
848 eprintln!("Not implementing anything for impl {} as the type is not understood (probably C-not exported)", ident);
852 let mut gen_types = GenericTypes::new(Some(resolved_path.clone()));
853 if !gen_types.learn_generics(&i.generics, types) {
854 eprintln!("Not implementing anything for impl {} due to not understood generics", ident);
858 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
859 if let Some(trait_path) = i.trait_.as_ref() {
860 if trait_path.0.is_some() { unimplemented!(); }
861 if types.understood_c_path(&trait_path.1) {
862 let full_trait_path = types.resolve_path(&trait_path.1, None);
863 let trait_obj = *types.crate_types.traits.get(&full_trait_path).unwrap();
866 let supertrait_resolver;
867 walk_supertraits!(trait_obj, Some(&types), (
869 if let Some(supertrait) = types.crate_types.traits.get(s) {
870 supertrait_name = s.to_string();
871 supertrait_resolver = get_module_type_resolver!(supertrait_name, types.crate_libs, types.crate_types);
872 gen_types.learn_associated_types(&supertrait, &supertrait_resolver);
877 // We learn the associated types maping from the original trait object.
878 // That's great, except that they are unresolved idents, so if we learn
879 // mappings from a trai defined in a different file, we may mis-resolve or
880 // fail to resolve the mapped types. Thus, we have to construct a new
881 // resolver for the module that the trait was defined in here first.
882 let trait_resolver = get_module_type_resolver!(full_trait_path, types.crate_libs, types.crate_types);
883 gen_types.learn_associated_types(trait_obj, &trait_resolver);
884 let mut impl_associated_types = HashMap::new();
885 for item in i.items.iter() {
887 syn::ImplItem::Type(t) => {
888 if let syn::Type::Path(p) = &t.ty {
889 if let Some(id) = single_ident_generic_path_to_ident(&p.path) {
890 impl_associated_types.insert(&t.ident, id);
898 let export = export_status(&trait_obj.attrs);
900 ExportStatus::Export|ExportStatus::NotImplementable => {},
901 ExportStatus::NoExport|ExportStatus::TestOnly => return,
904 // For cases where we have a concrete native object which implements a
905 // trait and need to return the C-mapped version of the trait, provide a
906 // From<> implementation which does all the work to ensure free is handled
907 // properly. This way we can call this method from deep in the
908 // type-conversion logic without actually knowing the concrete native type.
909 if !resolved_path.starts_with(types.module_path) {
910 if !first_seg_is_stdlib(resolved_path.split("::").next().unwrap()) {
911 writeln!(w, "use crate::{}::native{} as native{};", resolved_path.rsplitn(2, "::").skip(1).next().unwrap(), ident, ident).unwrap();
912 writeln!(w, "use crate::{};", resolved_path).unwrap();
913 writeln!(w, "use crate::{}_free_void;", resolved_path).unwrap();
915 writeln!(w, "use {} as native{};", resolved_path, ident).unwrap();
918 writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
919 writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();
920 if is_type_unconstructable(&resolved_path) {
921 writeln!(w, "\t\tunreachable!();").unwrap();
923 writeln!(w, "\t\tlet mut rust_obj = {} {{ inner: ObjOps::heap_alloc(obj), is_owned: true }};", ident).unwrap();
924 writeln!(w, "\t\tlet mut ret = {}_as_{}(&rust_obj);", ident, trait_obj.ident).unwrap();
925 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();
926 writeln!(w, "\t\trust_obj.inner = std::ptr::null_mut();").unwrap();
927 writeln!(w, "\t\tret.free = Some({}_free_void);", ident).unwrap();
928 writeln!(w, "\t\tret").unwrap();
930 writeln!(w, "\t}}\n}}").unwrap();
931 if is_type_unconstructable(&resolved_path) {
932 // We don't bother with Struct_as_Trait conversion for types which must
933 // never be instantiated, so just return early.
937 writeln!(w, "/// Constructs a new {} which calls the relevant methods on this_arg.", trait_obj.ident).unwrap();
938 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();
939 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: &{}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
940 writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
941 writeln!(w, "\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},").unwrap();
942 writeln!(w, "\t\tfree: None,").unwrap();
944 macro_rules! write_meth {
945 ($m: expr, $trait: expr, $indent: expr) => {
946 let trait_method = $trait.items.iter().filter_map(|item| {
947 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
948 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
949 match export_status(&trait_method.attrs) {
950 ExportStatus::Export => {},
951 ExportStatus::NoExport => {
952 write!(w, "{}\t\t//XXX: Need to export {}\n", $indent, $m.sig.ident).unwrap();
955 ExportStatus::TestOnly => continue,
956 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
959 let mut printed = false;
960 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
961 if let syn::Type::Reference(r) = &**rtype {
962 write!(w, "\n\t\t{}{}: ", $indent, $m.sig.ident).unwrap();
963 types.write_empty_rust_val(Some(&gen_types), w, &*r.elem);
964 writeln!(w, ",\n{}\t\tset_{}: Some({}_{}_set_{}),", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
969 write!(w, "{}\t\t{}: {}_{}_{},\n", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
973 for item in trait_obj.items.iter() {
975 syn::TraitItem::Method(m) => {
976 write_meth!(m, trait_obj, "");
981 let mut requires_clone = false;
982 walk_supertraits!(trait_obj, Some(&types), (
984 requires_clone = true;
985 writeln!(w, "\t\tcloned: Some({}_{}_cloned),", trait_obj.ident, ident).unwrap();
987 ("Sync", _) => {}, ("Send", _) => {},
988 ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
989 ("core::fmt::Debug", _) => {},
991 if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
992 writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();
993 writeln!(w, "\t\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},").unwrap();
994 writeln!(w, "\t\t\tfree: None,").unwrap();
995 for item in supertrait_obj.items.iter() {
997 syn::TraitItem::Method(m) => {
998 write_meth!(m, supertrait_obj, "\t");
1003 write!(w, "\t\t}},\n").unwrap();
1005 write_trait_impl_field_assign(w, s, ident);
1009 writeln!(w, "\t}}\n}}\n").unwrap();
1011 macro_rules! impl_meth {
1012 ($m: expr, $trait_meth: expr, $trait_path: expr, $trait: expr, $indent: expr) => {
1013 let trait_method = $trait.items.iter().filter_map(|item| {
1014 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
1015 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
1016 match export_status(&trait_method.attrs) {
1017 ExportStatus::Export => {},
1018 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1019 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1022 if let syn::ReturnType::Type(_, _) = &$m.sig.output {
1023 writeln!(w, "#[must_use]").unwrap();
1025 write!(w, "extern \"C\" fn {}_{}_{}(", ident, $trait.ident, $m.sig.ident).unwrap();
1026 let mut meth_gen_types = gen_types.push_ctx();
1027 assert!(meth_gen_types.learn_generics(&$m.sig.generics, types));
1028 let mut uncallable_function = false;
1029 for inp in $m.sig.inputs.iter() {
1031 syn::FnArg::Typed(arg) => {
1032 if types.skip_arg(&*arg.ty, Some(&meth_gen_types)) { continue; }
1033 let mut c_type = Vec::new();
1034 types.write_c_type(&mut c_type, &*arg.ty, Some(&meth_gen_types), false);
1035 if is_type_unconstructable(&String::from_utf8(c_type).unwrap()) {
1036 uncallable_function = true;
1042 if uncallable_function {
1043 let mut trait_resolver = get_module_type_resolver!(full_trait_path, types.crate_libs, types.crate_types);
1044 write_method_params(w, &$trait_meth.sig, "c_void", &mut trait_resolver, Some(&meth_gen_types), true, true);
1046 write_method_params(w, &$m.sig, "c_void", types, Some(&meth_gen_types), true, true);
1048 write!(w, " {{\n\t").unwrap();
1049 if uncallable_function {
1050 write!(w, "unreachable!();").unwrap();
1052 write_method_var_decl_body(w, &$m.sig, "", types, Some(&meth_gen_types), false);
1053 let mut takes_self = false;
1054 for inp in $m.sig.inputs.iter() {
1055 if let syn::FnArg::Receiver(_) = inp {
1060 let mut t_gen_args = String::new();
1061 for (idx, _) in $trait.generics.params.iter().enumerate() {
1062 if idx != 0 { t_gen_args += ", " };
1066 write!(w, "<native{} as {}<{}>>::{}(unsafe {{ &mut *(this_arg as *mut native{}) }}, ", ident, $trait_path, t_gen_args, $m.sig.ident, ident).unwrap();
1068 write!(w, "<native{} as {}<{}>>::{}(", ident, $trait_path, t_gen_args, $m.sig.ident).unwrap();
1071 let mut real_type = "".to_string();
1072 match &$m.sig.output {
1073 syn::ReturnType::Type(_, rtype) => {
1074 if let Some(mut remaining_path) = first_seg_self(&*rtype) {
1075 if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
1076 real_type = format!("{}", impl_associated_types.get(associated_seg).unwrap());
1082 write_method_call_params(w, &$m.sig, "", types, Some(&meth_gen_types), &real_type, false);
1084 write!(w, "\n}}\n").unwrap();
1085 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
1086 if let syn::Type::Reference(r) = &**rtype {
1087 assert_eq!($m.sig.inputs.len(), 1); // Must only take self
1088 writeln!(w, "extern \"C\" fn {}_{}_set_{}(trait_self_arg: &{}) {{", ident, $trait.ident, $m.sig.ident, $trait.ident).unwrap();
1089 writeln!(w, "\t// This is a bit race-y in the general case, but for our specific use-cases today, we're safe").unwrap();
1090 writeln!(w, "\t// Specifically, we must ensure that the first time we're called it can never be in parallel").unwrap();
1091 write!(w, "\tif ").unwrap();
1092 types.write_empty_rust_val_check(Some(&meth_gen_types), w, &*r.elem, &format!("trait_self_arg.{}", $m.sig.ident));
1093 writeln!(w, " {{").unwrap();
1094 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();
1095 writeln!(w, "\t}}").unwrap();
1096 writeln!(w, "}}").unwrap();
1102 'impl_item_loop: for item in i.items.iter() {
1104 syn::ImplItem::Method(m) => {
1105 for trait_item in trait_obj.items.iter() {
1107 syn::TraitItem::Method(meth) => {
1108 if meth.sig.ident == m.sig.ident {
1109 impl_meth!(m, meth, full_trait_path, trait_obj, "");
1110 continue 'impl_item_loop;
1118 syn::ImplItem::Type(_) => {},
1119 _ => unimplemented!(),
1123 writeln!(w, "extern \"C\" fn {}_{}_cloned(new_obj: &mut crate::{}) {{", trait_obj.ident, ident, full_trait_path).unwrap();
1124 writeln!(w, "\tnew_obj.this_arg = {}_clone_void(new_obj.this_arg);", ident).unwrap();
1125 writeln!(w, "\tnew_obj.free = Some({}_free_void);", ident).unwrap();
1126 walk_supertraits!(trait_obj, Some(&types), (
1128 if types.crate_types.traits.get(s).is_some() {
1129 assert!(!types.is_clonable(s)); // We don't currently support cloning with a clonable supertrait
1130 writeln!(w, "\tnew_obj.{}.this_arg = new_obj.this_arg;", t).unwrap();
1131 writeln!(w, "\tnew_obj.{}.free = None;", t).unwrap();
1135 writeln!(w, "}}").unwrap();
1137 write!(w, "\n").unwrap();
1140 if is_type_unconstructable(&resolved_path) {
1141 // Don't bother exposing trait implementations for objects which cannot be
1145 if path_matches_nongeneric(&trait_path.1, &["From"]) {
1146 } else if path_matches_nongeneric(&trait_path.1, &["Default"]) {
1147 writeln!(w, "/// Creates a \"default\" {}. See struct and individual field documentaiton for details on which values are used.", ident).unwrap();
1148 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_default() -> {} {{\n", ident, ident).unwrap();
1149 write!(w, "\t{} {{ inner: ObjOps::heap_alloc(Default::default()), is_owned: true }}\n", ident).unwrap();
1150 write!(w, "}}\n").unwrap();
1151 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "PartialEq"]) {
1152 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "Eq"]) {
1153 writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap();
1154 writeln!(w, "/// This ignores pointers and is_owned flags and looks at the values in fields.").unwrap();
1155 if types.c_type_has_inner_from_path(&resolved_path) {
1156 writeln!(w, "/// Two objects with NULL inner values will be considered \"equal\" here.").unwrap();
1158 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_eq(a: &{}, b: &{}) -> bool {{\n", ident, ident, ident).unwrap();
1159 if types.c_type_has_inner_from_path(&resolved_path) {
1160 write!(w, "\tif a.inner == b.inner {{ return true; }}\n").unwrap();
1161 write!(w, "\tif a.inner.is_null() || b.inner.is_null() {{ return false; }}\n").unwrap();
1165 let ref_type: syn::Type = syn::parse_quote!(&#path);
1166 assert!(!types.write_to_c_conversion_new_var(w, &format_ident!("a"), &*i.self_ty, Some(&gen_types), false), "We don't support new var conversions when comparing equality");
1168 write!(w, "\tif ").unwrap();
1169 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1170 write!(w, "a").unwrap();
1171 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1172 write!(w, " == ").unwrap();
1173 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1174 write!(w, "b").unwrap();
1175 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1177 writeln!(w, " {{ true }} else {{ false }}\n}}").unwrap();
1178 } else if path_matches_nongeneric(&trait_path.1, &["core", "hash", "Hash"]) {
1179 writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap();
1180 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_hash(o: &{}) -> u64 {{\n", ident, ident).unwrap();
1181 if types.c_type_has_inner_from_path(&resolved_path) {
1182 write!(w, "\tif o.inner.is_null() {{ return 0; }}\n").unwrap();
1186 let ref_type: syn::Type = syn::parse_quote!(&#path);
1187 assert!(!types.write_to_c_conversion_new_var(w, &format_ident!("a"), &*i.self_ty, Some(&gen_types), false), "We don't support new var conversions when comparing equality");
1189 writeln!(w, "\t// Note that we'd love to use std::collections::hash_map::DefaultHasher but it's not in core").unwrap();
1190 writeln!(w, "\t#[allow(deprecated)]").unwrap();
1191 writeln!(w, "\tlet mut hasher = core::hash::SipHasher::new();").unwrap();
1192 write!(w, "\tstd::hash::Hash::hash(").unwrap();
1193 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1194 write!(w, "o").unwrap();
1195 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1196 writeln!(w, ", &mut hasher);").unwrap();
1197 writeln!(w, "\tstd::hash::Hasher::finish(&hasher)\n}}").unwrap();
1198 } else if (path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) || path_matches_nongeneric(&trait_path.1, &["Clone"])) &&
1199 types.c_type_has_inner_from_path(&resolved_path) {
1200 writeln!(w, "impl Clone for {} {{", ident).unwrap();
1201 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
1202 writeln!(w, "\t\tSelf {{").unwrap();
1203 writeln!(w, "\t\t\tinner: if <*mut native{}>::is_null(self.inner) {{ std::ptr::null_mut() }} else {{", ident).unwrap();
1204 writeln!(w, "\t\t\t\tObjOps::heap_alloc(unsafe {{ &*ObjOps::untweak_ptr(self.inner) }}.clone()) }},").unwrap();
1205 writeln!(w, "\t\t\tis_owned: true,").unwrap();
1206 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
1207 writeln!(w, "#[allow(unused)]").unwrap();
1208 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
1209 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", ident).unwrap();
1210 writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", ident).unwrap();
1211 writeln!(w, "}}").unwrap();
1212 writeln!(w, "#[no_mangle]").unwrap();
1213 writeln!(w, "/// Creates a copy of the {}", ident).unwrap();
1214 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", ident, ident, ident).unwrap();
1215 writeln!(w, "\torig.clone()").unwrap();
1216 writeln!(w, "}}").unwrap();
1217 } else if path_matches_nongeneric(&trait_path.1, &["FromStr"]) {
1218 if let Some(container) = types.get_c_mangled_container_type(
1219 vec![&*i.self_ty, &syn::Type::Tuple(syn::TypeTuple { paren_token: Default::default(), elems: syn::punctuated::Punctuated::new() })],
1220 Some(&gen_types), "Result") {
1221 writeln!(w, "#[no_mangle]").unwrap();
1222 writeln!(w, "/// Read a {} object from a string", ident).unwrap();
1223 writeln!(w, "pub extern \"C\" fn {}_from_str(s: crate::c_types::Str) -> {} {{", ident, container).unwrap();
1224 writeln!(w, "\tmatch {}::from_str(s.into_str()) {{", resolved_path).unwrap();
1225 writeln!(w, "\t\tOk(r) => {{").unwrap();
1226 let new_var = types.write_to_c_conversion_new_var(w, &format_ident!("r"), &*i.self_ty, Some(&gen_types), false);
1227 write!(w, "\t\t\tcrate::c_types::CResultTempl::ok(\n\t\t\t\t").unwrap();
1228 types.write_to_c_conversion_inline_prefix(w, &*i.self_ty, Some(&gen_types), false);
1229 write!(w, "{}r", if new_var { "local_" } else { "" }).unwrap();
1230 types.write_to_c_conversion_inline_suffix(w, &*i.self_ty, Some(&gen_types), false);
1231 writeln!(w, "\n\t\t\t)\n\t\t}},").unwrap();
1232 writeln!(w, "\t\tErr(e) => crate::c_types::CResultTempl::err(()),").unwrap();
1233 writeln!(w, "\t}}.into()\n}}").unwrap();
1235 } else if path_matches_nongeneric(&trait_path.1, &["Display"]) {
1236 writeln!(w, "#[no_mangle]").unwrap();
1237 writeln!(w, "/// Get the string representation of a {} object", ident).unwrap();
1238 writeln!(w, "pub extern \"C\" fn {}_to_str(o: &crate::{}) -> Str {{", ident, resolved_path).unwrap();
1240 let self_ty = &i.self_ty;
1241 let ref_type: syn::Type = syn::parse_quote!(&#self_ty);
1242 let new_var = types.write_from_c_conversion_new_var(w, &format_ident!("o"), &ref_type, Some(&gen_types));
1243 write!(w, "\tformat!(\"{{}}\", ").unwrap();
1244 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1245 write!(w, "{}o", if new_var { "local_" } else { "" }).unwrap();
1246 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1247 writeln!(w, ").into()").unwrap();
1249 writeln!(w, "}}").unwrap();
1251 //XXX: implement for other things like ToString
1252 // If we have no generics, try a manual implementation:
1253 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
1256 let declared_type = (*types.get_declared_type(&ident).unwrap()).clone();
1257 for item in i.items.iter() {
1259 syn::ImplItem::Method(m) => {
1260 if let syn::Visibility::Public(_) = m.vis {
1261 match export_status(&m.attrs) {
1262 ExportStatus::Export => {},
1263 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1264 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1266 let mut meth_gen_types = gen_types.push_ctx();
1267 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
1268 if m.defaultness.is_some() { unimplemented!(); }
1269 writeln_fn_docs(w, &m.attrs, "", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
1270 if let syn::ReturnType::Type(_, _) = &m.sig.output {
1271 writeln!(w, "#[must_use]").unwrap();
1273 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}(", ident, m.sig.ident).unwrap();
1274 let ret_type = match &declared_type {
1275 DeclType::MirroredEnum => format!("{}", ident),
1276 DeclType::StructImported {..} => format!("{}", ident),
1277 _ => unimplemented!(),
1279 write_method_params(w, &m.sig, &ret_type, types, Some(&meth_gen_types), false, true);
1280 write!(w, " {{\n\t").unwrap();
1281 write_method_var_decl_body(w, &m.sig, "", types, Some(&meth_gen_types), false);
1282 let mut takes_self = false;
1283 let mut takes_mut_self = false;
1284 let mut takes_owned_self = false;
1285 for inp in m.sig.inputs.iter() {
1286 if let syn::FnArg::Receiver(r) = inp {
1288 if r.mutability.is_some() { takes_mut_self = true; }
1289 if r.reference.is_none() { takes_owned_self = true; }
1292 if !takes_mut_self && !takes_self {
1293 write!(w, "{}::{}(", resolved_path, m.sig.ident).unwrap();
1295 match &declared_type {
1296 DeclType::MirroredEnum => write!(w, "this_arg.to_native().{}(", m.sig.ident).unwrap(),
1297 DeclType::StructImported {..} => {
1298 if takes_owned_self {
1299 write!(w, "(*unsafe {{ Box::from_raw(this_arg.take_inner()) }}).{}(", m.sig.ident).unwrap();
1300 } else if takes_mut_self {
1301 write!(w, "unsafe {{ &mut (*ObjOps::untweak_ptr(this_arg.inner as *mut native{})) }}.{}(", ident, m.sig.ident).unwrap();
1303 write!(w, "unsafe {{ &*ObjOps::untweak_ptr(this_arg.inner) }}.{}(", m.sig.ident).unwrap();
1306 _ => unimplemented!(),
1309 write_method_call_params(w, &m.sig, "", types, Some(&meth_gen_types), &ret_type, false);
1310 writeln!(w, "\n}}\n").unwrap();
1317 } else if let Some(resolved_path) = types.maybe_resolve_ident(&ident) {
1318 if let Some(aliases) = types.crate_types.reverse_alias_map.get(&resolved_path).cloned() {
1319 'alias_impls: for (alias, arguments) in aliases {
1320 let alias_resolved = types.resolve_path(&alias, None);
1321 for (idx, gen) in i.generics.params.iter().enumerate() {
1323 syn::GenericParam::Type(type_param) => {
1324 'bounds_check: for bound in type_param.bounds.iter() {
1325 if let syn::TypeParamBound::Trait(trait_bound) = bound {
1326 if let syn::PathArguments::AngleBracketed(ref t) = &arguments {
1327 assert!(idx < t.args.len());
1328 if let syn::GenericArgument::Type(syn::Type::Path(p)) = &t.args[idx] {
1329 let generic_arg = types.resolve_path(&p.path, None);
1330 let generic_bound = types.resolve_path(&trait_bound.path, None);
1331 if let Some(traits_impld) = types.crate_types.trait_impls.get(&generic_arg) {
1332 for trait_impld in traits_impld {
1333 if *trait_impld == generic_bound { continue 'bounds_check; }
1335 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1336 continue 'alias_impls;
1338 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1339 continue 'alias_impls;
1341 } else { unimplemented!(); }
1342 } else { unimplemented!(); }
1343 } else { unimplemented!(); }
1346 syn::GenericParam::Lifetime(_) => {},
1347 syn::GenericParam::Const(_) => unimplemented!(),
1350 let aliased_impl = syn::ItemImpl {
1351 attrs: i.attrs.clone(),
1352 brace_token: syn::token::Brace(Span::call_site()),
1354 generics: syn::Generics {
1356 params: syn::punctuated::Punctuated::new(),
1360 impl_token: syn::Token![impl](Span::call_site()),
1361 items: i.items.clone(),
1362 self_ty: Box::new(syn::Type::Path(syn::TypePath { qself: None, path: alias.clone() })),
1363 trait_: i.trait_.clone(),
1366 writeln_impl(w, &aliased_impl, types);
1369 eprintln!("Not implementing anything for {} due to it being marked not exported", ident);
1372 eprintln!("Not implementing anything for {} due to no-resolve (probably the type isn't pub)", ident);
1378 /// Replaces upper case charachters with underscore followed by lower case except the first
1379 /// charachter and repeated upper case characthers (which are only made lower case).
1380 fn camel_to_snake_case(camel: &str) -> String {
1381 let mut res = "".to_string();
1382 let mut last_upper = -1;
1383 for (idx, c) in camel.chars().enumerate() {
1384 if c.is_uppercase() {
1385 if last_upper != idx as isize - 1 { res.push('_'); }
1386 res.push(c.to_lowercase().next().unwrap());
1387 last_upper = idx as isize;
1396 /// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum
1397 /// is unitary), we generate an equivalent enum with all types replaced with their C mapped
1398 /// versions followed by conversion functions which map between the Rust version and the C mapped
1400 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) {
1401 match export_status(&e.attrs) {
1402 ExportStatus::Export => {},
1403 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1404 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1407 if is_enum_opaque(e) {
1408 eprintln!("Skipping enum {} as it contains non-unit fields", e.ident);
1409 writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers);
1412 writeln_docs(w, &e.attrs, "");
1414 let mut gen_types = GenericTypes::new(None);
1415 assert!(gen_types.learn_generics(&e.generics, types));
1417 let mut needs_free = false;
1418 let mut constr = Vec::new();
1420 writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap();
1421 for var in e.variants.iter() {
1422 assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum
1423 writeln_docs(w, &var.attrs, "\t");
1424 write!(w, "\t{}", var.ident).unwrap();
1425 writeln!(&mut constr, "#[no_mangle]\n/// Utility method to constructs a new {}-variant {}", var.ident, e.ident).unwrap();
1426 let constr_name = camel_to_snake_case(&format!("{}", var.ident));
1427 write!(&mut constr, "pub extern \"C\" fn {}_{}(", e.ident, constr_name).unwrap();
1428 let mut empty_tuple_variant = false;
1429 if let syn::Fields::Named(fields) = &var.fields {
1431 writeln!(w, " {{").unwrap();
1432 for (idx, field) in fields.named.iter().enumerate() {
1433 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1434 writeln_field_docs(w, &field.attrs, "\t\t", types, Some(&gen_types), &field.ty);
1435 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1436 write!(&mut constr, "{}{}: ", if idx != 0 { ", " } else { "" }, field.ident.as_ref().unwrap()).unwrap();
1437 types.write_c_type(w, &field.ty, Some(&gen_types), false);
1438 types.write_c_type(&mut constr, &field.ty, Some(&gen_types), false);
1439 writeln!(w, ",").unwrap();
1441 write!(w, "\t}}").unwrap();
1442 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1443 if fields.unnamed.len() == 1 {
1444 let mut empty_check = Vec::new();
1445 types.write_c_type(&mut empty_check, &fields.unnamed[0].ty, Some(&gen_types), false);
1446 if empty_check.is_empty() {
1447 empty_tuple_variant = true;
1450 if !empty_tuple_variant {
1452 write!(w, "(").unwrap();
1453 for (idx, field) in fields.unnamed.iter().enumerate() {
1454 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1455 write!(&mut constr, "{}: ", ('a' as u8 + idx as u8) as char).unwrap();
1456 types.write_c_type(w, &field.ty, Some(&gen_types), false);
1457 types.write_c_type(&mut constr, &field.ty, Some(&gen_types), false);
1458 if idx != fields.unnamed.len() - 1 {
1459 write!(w, ",").unwrap();
1460 write!(&mut constr, ",").unwrap();
1463 write!(w, ")").unwrap();
1466 if var.discriminant.is_some() { unimplemented!(); }
1467 write!(&mut constr, ") -> {} {{\n\t{}::{}", e.ident, e.ident, var.ident).unwrap();
1468 if let syn::Fields::Named(fields) = &var.fields {
1469 writeln!(&mut constr, " {{").unwrap();
1470 for field in fields.named.iter() {
1471 writeln!(&mut constr, "\t\t{},", field.ident.as_ref().unwrap()).unwrap();
1473 writeln!(&mut constr, "\t}}").unwrap();
1474 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1475 if !empty_tuple_variant {
1476 write!(&mut constr, "(").unwrap();
1477 for idx in 0..fields.unnamed.len() {
1478 write!(&mut constr, "{}, ", ('a' as u8 + idx as u8) as char).unwrap();
1480 writeln!(&mut constr, ")").unwrap();
1482 writeln!(&mut constr, "").unwrap();
1485 writeln!(&mut constr, "}}").unwrap();
1486 writeln!(w, ",").unwrap();
1488 writeln!(w, "}}\nuse {}::{} as native{};\nimpl {} {{", types.module_path, e.ident, e.ident, e.ident).unwrap();
1490 macro_rules! write_conv {
1491 ($fn_sig: expr, $to_c: expr, $ref: expr) => {
1492 writeln!(w, "\t#[allow(unused)]\n\tpub(crate) fn {} {{\n\t\tmatch {} {{", $fn_sig, if $to_c { "native" } else { "self" }).unwrap();
1493 for var in e.variants.iter() {
1494 write!(w, "\t\t\t{}{}::{} ", if $to_c { "native" } else { "" }, e.ident, var.ident).unwrap();
1495 let mut empty_tuple_variant = false;
1496 if let syn::Fields::Named(fields) = &var.fields {
1497 write!(w, "{{").unwrap();
1498 for field in fields.named.iter() {
1499 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1500 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, field.ident.as_ref().unwrap()).unwrap();
1502 write!(w, "}} ").unwrap();
1503 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1504 if fields.unnamed.len() == 1 {
1505 let mut empty_check = Vec::new();
1506 types.write_c_type(&mut empty_check, &fields.unnamed[0].ty, Some(&gen_types), false);
1507 if empty_check.is_empty() {
1508 empty_tuple_variant = true;
1511 if !empty_tuple_variant || $to_c {
1512 write!(w, "(").unwrap();
1513 for (idx, field) in fields.unnamed.iter().enumerate() {
1514 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1515 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, ('a' as u8 + idx as u8) as char).unwrap();
1517 write!(w, ") ").unwrap();
1520 write!(w, "=>").unwrap();
1522 macro_rules! handle_field_a {
1523 ($field: expr, $field_ident: expr) => { {
1524 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1525 let mut sink = ::std::io::sink();
1526 let mut out: &mut dyn std::io::Write = if $ref { &mut sink } else { w };
1527 let new_var = if $to_c {
1528 types.write_to_c_conversion_new_var(&mut out, $field_ident, &$field.ty, Some(&gen_types), false)
1530 types.write_from_c_conversion_new_var(&mut out, $field_ident, &$field.ty, Some(&gen_types))
1532 if $ref || new_var {
1534 write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", $field_ident, $field_ident).unwrap();
1536 let nonref_ident = format_ident!("{}_nonref", $field_ident);
1538 types.write_to_c_conversion_new_var(w, &nonref_ident, &$field.ty, Some(&gen_types), false);
1540 types.write_from_c_conversion_new_var(w, &nonref_ident, &$field.ty, Some(&gen_types));
1542 write!(w, "\n\t\t\t\t").unwrap();
1545 write!(w, "\n\t\t\t\t").unwrap();
1550 if let syn::Fields::Named(fields) = &var.fields {
1551 write!(w, " {{\n\t\t\t\t").unwrap();
1552 for field in fields.named.iter() {
1553 handle_field_a!(field, field.ident.as_ref().unwrap());
1555 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1556 write!(w, " {{\n\t\t\t\t").unwrap();
1557 for (idx, field) in fields.unnamed.iter().enumerate() {
1558 if !empty_tuple_variant {
1559 handle_field_a!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1562 } else { write!(w, " ").unwrap(); }
1564 write!(w, "{}{}::{}", if $to_c { "" } else { "native" }, e.ident, var.ident).unwrap();
1566 macro_rules! handle_field_b {
1567 ($field: expr, $field_ident: expr) => { {
1568 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1570 types.write_to_c_conversion_inline_prefix(w, &$field.ty, Some(&gen_types), false);
1572 types.write_from_c_conversion_prefix(w, &$field.ty, Some(&gen_types));
1574 write!(w, "{}{}", $field_ident,
1575 if $ref { "_nonref" } else { "" }).unwrap();
1577 types.write_to_c_conversion_inline_suffix(w, &$field.ty, Some(&gen_types), false);
1579 types.write_from_c_conversion_suffix(w, &$field.ty, Some(&gen_types));
1581 write!(w, ",").unwrap();
1585 if let syn::Fields::Named(fields) = &var.fields {
1586 write!(w, " {{").unwrap();
1587 for field in fields.named.iter() {
1588 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1589 write!(w, "\n\t\t\t\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1590 handle_field_b!(field, field.ident.as_ref().unwrap());
1592 writeln!(w, "\n\t\t\t\t}}").unwrap();
1593 write!(w, "\t\t\t}}").unwrap();
1594 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1595 if !empty_tuple_variant || !$to_c {
1596 write!(w, " (").unwrap();
1597 for (idx, field) in fields.unnamed.iter().enumerate() {
1598 write!(w, "\n\t\t\t\t\t").unwrap();
1599 handle_field_b!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1601 writeln!(w, "\n\t\t\t\t)").unwrap();
1603 write!(w, "\t\t\t}}").unwrap();
1605 writeln!(w, ",").unwrap();
1607 writeln!(w, "\t\t}}\n\t}}").unwrap();
1611 write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true);
1612 write_conv!(format!("into_native(self) -> native{}", e.ident), false, false);
1613 write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true);
1614 write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false);
1615 writeln!(w, "}}").unwrap();
1618 writeln!(w, "/// Frees any resources used by the {}", e.ident).unwrap();
1619 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap();
1621 writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap();
1622 writeln!(w, "#[no_mangle]").unwrap();
1623 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap();
1624 writeln!(w, "\torig.clone()").unwrap();
1625 writeln!(w, "}}").unwrap();
1626 w.write_all(&constr).unwrap();
1627 write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free, None);
1630 fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) {
1631 match export_status(&f.attrs) {
1632 ExportStatus::Export => {},
1633 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1634 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1636 let mut gen_types = GenericTypes::new(None);
1637 if !gen_types.learn_generics(&f.sig.generics, types) { return; }
1639 writeln_fn_docs(w, &f.attrs, "", types, Some(&gen_types), f.sig.inputs.iter(), &f.sig.output);
1641 write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap();
1642 write_method_params(w, &f.sig, "", types, Some(&gen_types), false, true);
1643 write!(w, " {{\n\t").unwrap();
1644 write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false);
1645 write!(w, "{}::{}(", types.module_path, f.sig.ident).unwrap();
1646 write_method_call_params(w, &f.sig, "", types, Some(&gen_types), "", false);
1647 writeln!(w, "\n}}\n").unwrap();
1650 // ********************************
1651 // *** File/Crate Walking Logic ***
1652 // ********************************
1654 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) {
1655 // We want to ignore all items declared in this module (as they are not pub), but we still need
1656 // to give the ImportResolver any use statements, so we copy them here.
1657 let mut use_items = Vec::new();
1658 for item in module.content.as_ref().unwrap().1.iter() {
1659 if let syn::Item::Use(_) = item {
1660 use_items.push(item);
1663 let import_resolver = ImportResolver::from_borrowed_items(mod_path.splitn(2, "::").next().unwrap(), &libast.dependencies, mod_path, &use_items);
1664 let mut types = TypeResolver::new(mod_path, import_resolver, crate_types);
1666 writeln!(w, "mod {} {{\n{}", module.ident, DEFAULT_IMPORTS).unwrap();
1667 for item in module.content.as_ref().unwrap().1.iter() {
1669 syn::Item::Mod(m) => convert_priv_mod(w, libast, crate_types, out_dir, &format!("{}::{}", mod_path, module.ident), m),
1670 syn::Item::Impl(i) => {
1671 if let &syn::Type::Path(ref p) = &*i.self_ty {
1672 if p.path.get_ident().is_some() {
1673 writeln_impl(w, i, &mut types);
1680 writeln!(w, "}}").unwrap();
1683 /// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at
1684 /// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST
1685 /// at `module` from C.
1686 fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>, out_dir: &str, header_file: &mut File, cpp_header_file: &mut File) {
1687 for (module, astmod) in libast.modules.iter() {
1688 let orig_crate = module.splitn(2, "::").next().unwrap();
1689 let ASTModule { ref attrs, ref items, ref submods } = astmod;
1690 assert_eq!(export_status(&attrs), ExportStatus::Export);
1692 let new_file_path = if submods.is_empty() {
1693 format!("{}/{}.rs", out_dir, module.replace("::", "/"))
1694 } else if module != "" {
1695 format!("{}/{}/mod.rs", out_dir, module.replace("::", "/"))
1697 format!("{}/lib.rs", out_dir)
1699 let _ = std::fs::create_dir((&new_file_path.as_ref() as &std::path::Path).parent().unwrap());
1700 let mut out = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1701 .open(new_file_path).expect("Unable to open new src file");
1703 writeln!(out, "// This file is Copyright its original authors, visible in version control").unwrap();
1704 writeln!(out, "// history and in the source files from which this was generated.").unwrap();
1705 writeln!(out, "//").unwrap();
1706 writeln!(out, "// This file is licensed under the license available in the LICENSE or LICENSE.md").unwrap();
1707 writeln!(out, "// file in the root of this repository or, if no such file exists, the same").unwrap();
1708 writeln!(out, "// license as that which applies to the original source files from which this").unwrap();
1709 writeln!(out, "// source was automatically generated.").unwrap();
1710 writeln!(out, "").unwrap();
1712 writeln_docs(&mut out, &attrs, "");
1715 // Special-case the top-level lib.rs with various lint allows and a pointer to the c_types
1716 // and bitcoin hand-written modules.
1717 writeln!(out, "//! C Bindings").unwrap();
1718 writeln!(out, "#![allow(unknown_lints)]").unwrap();
1719 writeln!(out, "#![allow(non_camel_case_types)]").unwrap();
1720 writeln!(out, "#![allow(non_snake_case)]").unwrap();
1721 writeln!(out, "#![allow(unused_imports)]").unwrap();
1722 writeln!(out, "#![allow(unused_variables)]").unwrap();
1723 writeln!(out, "#![allow(unused_mut)]").unwrap();
1724 writeln!(out, "#![allow(unused_parens)]").unwrap();
1725 writeln!(out, "#![allow(unused_unsafe)]").unwrap();
1726 writeln!(out, "#![allow(unused_braces)]").unwrap();
1727 // TODO: We need to map deny(missing_docs) in the source crate(s)
1728 //writeln!(out, "#![deny(missing_docs)]").unwrap();
1729 writeln!(out, "pub mod version;").unwrap();
1730 writeln!(out, "pub mod c_types;").unwrap();
1731 writeln!(out, "pub mod bitcoin;").unwrap();
1733 writeln!(out, "{}", DEFAULT_IMPORTS).unwrap();
1737 writeln!(out, "pub mod {};", m).unwrap();
1740 eprintln!("Converting {} entries...", module);
1742 let import_resolver = ImportResolver::new(orig_crate, &libast.dependencies, module, items);
1743 let mut type_resolver = TypeResolver::new(module, import_resolver, crate_types);
1745 for item in items.iter() {
1747 syn::Item::Use(_) => {}, // Handled above
1748 syn::Item::Static(_) => {},
1749 syn::Item::Enum(e) => {
1750 if let syn::Visibility::Public(_) = e.vis {
1751 writeln_enum(&mut out, &e, &mut type_resolver, header_file, cpp_header_file);
1754 syn::Item::Impl(i) => {
1755 writeln_impl(&mut out, &i, &mut type_resolver);
1757 syn::Item::Struct(s) => {
1758 if let syn::Visibility::Public(_) = s.vis {
1759 writeln_struct(&mut out, &s, &mut type_resolver, header_file, cpp_header_file);
1762 syn::Item::Trait(t) => {
1763 if let syn::Visibility::Public(_) = t.vis {
1764 writeln_trait(&mut out, &t, &mut type_resolver, header_file, cpp_header_file);
1767 syn::Item::Mod(m) => {
1768 convert_priv_mod(&mut out, libast, crate_types, out_dir, &format!("{}::{}", module, m.ident), m);
1770 syn::Item::Const(c) => {
1771 // Re-export any primitive-type constants.
1772 if let syn::Visibility::Public(_) = c.vis {
1773 if let syn::Type::Path(p) = &*c.ty {
1774 let resolved_path = type_resolver.resolve_path(&p.path, None);
1775 if type_resolver.is_primitive(&resolved_path) {
1776 writeln_field_docs(&mut out, &c.attrs, "", &mut type_resolver, None, &*c.ty);
1777 writeln!(out, "\n#[no_mangle]").unwrap();
1778 writeln!(out, "pub static {}: {} = {}::{};", c.ident, resolved_path, module, c.ident).unwrap();
1783 syn::Item::Type(t) => {
1784 if let syn::Visibility::Public(_) = t.vis {
1785 match export_status(&t.attrs) {
1786 ExportStatus::Export => {},
1787 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1788 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1791 let mut process_alias = true;
1792 for tok in t.generics.params.iter() {
1793 if let syn::GenericParam::Lifetime(_) = tok {}
1794 else { process_alias = false; }
1798 syn::Type::Path(_) =>
1799 writeln_opaque(&mut out, &t.ident, &format!("{}", t.ident), &t.generics, &t.attrs, &type_resolver, header_file, cpp_header_file),
1805 syn::Item::Fn(f) => {
1806 if let syn::Visibility::Public(_) = f.vis {
1807 writeln_fn(&mut out, &f, &mut type_resolver);
1810 syn::Item::Macro(_) => {},
1811 syn::Item::Verbatim(_) => {},
1812 syn::Item::ExternCrate(_) => {},
1813 _ => unimplemented!(),
1817 out.flush().unwrap();
1821 fn walk_private_mod<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, module: String, items: &'a syn::ItemMod, crate_types: &mut CrateTypes<'a>) {
1822 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, &module, &items.content.as_ref().unwrap().1);
1823 for item in items.content.as_ref().unwrap().1.iter() {
1825 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1826 syn::Item::Impl(i) => {
1827 if let &syn::Type::Path(ref p) = &*i.self_ty {
1828 if let Some(trait_path) = i.trait_.as_ref() {
1829 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1830 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1831 match crate_types.trait_impls.entry(sp) {
1832 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1833 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1845 /// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes.
1846 fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) {
1847 for (module, astmod) in ast_storage.modules.iter() {
1848 let ASTModule { ref attrs, ref items, submods: _ } = astmod;
1849 assert_eq!(export_status(&attrs), ExportStatus::Export);
1850 let orig_crate = module.splitn(2, "::").next().unwrap();
1851 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, module, items);
1853 for item in items.iter() {
1855 syn::Item::Struct(s) => {
1856 if let syn::Visibility::Public(_) = s.vis {
1857 match export_status(&s.attrs) {
1858 ExportStatus::Export => {},
1859 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1860 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1862 let struct_path = format!("{}::{}", module, s.ident);
1863 crate_types.opaques.insert(struct_path, (&s.ident, &s.generics));
1866 syn::Item::Trait(t) => {
1867 if let syn::Visibility::Public(_) = t.vis {
1868 match export_status(&t.attrs) {
1869 ExportStatus::Export|ExportStatus::NotImplementable => {},
1870 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1872 let trait_path = format!("{}::{}", module, t.ident);
1873 walk_supertraits!(t, None, (
1875 crate_types.set_clonable("crate::".to_owned() + &trait_path);
1879 crate_types.traits.insert(trait_path, &t);
1882 syn::Item::Type(t) => {
1883 if let syn::Visibility::Public(_) = t.vis {
1884 match export_status(&t.attrs) {
1885 ExportStatus::Export => {},
1886 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1887 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1889 let type_path = format!("{}::{}", module, t.ident);
1890 let mut process_alias = true;
1891 for tok in t.generics.params.iter() {
1892 if let syn::GenericParam::Lifetime(_) = tok {}
1893 else { process_alias = false; }
1897 syn::Type::Path(p) => {
1898 let t_ident = &t.ident;
1900 // If its a path with no generics, assume we don't map the aliased type and map it opaque
1901 let path_obj = parse_quote!(#t_ident);
1902 let args_obj = p.path.segments.last().unwrap().arguments.clone();
1903 match crate_types.reverse_alias_map.entry(import_resolver.maybe_resolve_path(&p.path, None).unwrap()) {
1904 hash_map::Entry::Occupied(mut e) => { e.get_mut().push((path_obj, args_obj)); },
1905 hash_map::Entry::Vacant(e) => { e.insert(vec![(path_obj, args_obj)]); },
1908 crate_types.opaques.insert(type_path, (t_ident, &t.generics));
1911 crate_types.type_aliases.insert(type_path, import_resolver.resolve_imported_refs((*t.ty).clone()));
1917 syn::Item::Enum(e) if is_enum_opaque(e) => {
1918 if let syn::Visibility::Public(_) = e.vis {
1919 match export_status(&e.attrs) {
1920 ExportStatus::Export => {},
1921 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1922 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1924 let enum_path = format!("{}::{}", module, e.ident);
1925 crate_types.opaques.insert(enum_path, (&e.ident, &e.generics));
1928 syn::Item::Enum(e) => {
1929 if let syn::Visibility::Public(_) = e.vis {
1930 match export_status(&e.attrs) {
1931 ExportStatus::Export => {},
1932 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1933 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1935 let enum_path = format!("{}::{}", module, e.ident);
1936 crate_types.mirrored_enums.insert(enum_path, &e);
1939 syn::Item::Impl(i) => {
1940 if let &syn::Type::Path(ref p) = &*i.self_ty {
1941 if let Some(trait_path) = i.trait_.as_ref() {
1942 if path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) ||
1943 path_matches_nongeneric(&trait_path.1, &["Clone"]) {
1944 if let Some(full_path) = import_resolver.maybe_resolve_path(&p.path, None) {
1945 crate_types.set_clonable("crate::".to_owned() + &full_path);
1948 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1949 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1950 match crate_types.trait_impls.entry(sp) {
1951 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1952 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1959 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1967 let args: Vec<String> = env::args().collect();
1968 if args.len() != 5 {
1969 eprintln!("Usage: target/dir derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
1973 let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1974 .open(&args[2]).expect("Unable to open new header file");
1975 let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1976 .open(&args[3]).expect("Unable to open new header file");
1977 let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1978 .open(&args[4]).expect("Unable to open new header file");
1980 writeln!(header_file, "#if defined(__GNUC__)").unwrap();
1981 writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
1982 writeln!(header_file, "#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
1983 writeln!(header_file, "#else").unwrap();
1984 writeln!(header_file, "#define MUST_USE_STRUCT").unwrap();
1985 writeln!(header_file, "#define MUST_USE_RES").unwrap();
1986 writeln!(header_file, "#endif").unwrap();
1987 writeln!(header_file, "#if defined(__clang__)").unwrap();
1988 writeln!(header_file, "#define NONNULL_PTR _Nonnull").unwrap();
1989 writeln!(header_file, "#else").unwrap();
1990 writeln!(header_file, "#define NONNULL_PTR").unwrap();
1991 writeln!(header_file, "#endif").unwrap();
1992 writeln!(cpp_header_file, "#include <string.h>\nnamespace LDK {{").unwrap();
1994 // Write a few manually-defined types into the C++ header file
1995 write_cpp_wrapper(&mut cpp_header_file, "Str", true, None);
1997 // First parse the full crate's ASTs, caching them so that we can hold references to the AST
1998 // objects in other datastructures:
1999 let mut lib_src = String::new();
2000 std::io::stdin().lock().read_to_string(&mut lib_src).unwrap();
2001 let lib_syntax = syn::parse_file(&lib_src).expect("Unable to parse file");
2002 let libast = FullLibraryAST::load_lib(lib_syntax);
2004 // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
2005 // when parsing other file ASTs...
2006 let mut libtypes = CrateTypes::new(&mut derived_templates, &libast);
2007 walk_ast(&libast, &mut libtypes);
2009 // ... finally, do the actual file conversion/mapping, writing out types as we go.
2010 convert_file(&libast, &libtypes, &args[1], &mut header_file, &mut cpp_header_file);
2012 // For container templates which we created while walking the crate, make sure we add C++
2013 // mapped types so that C++ users can utilize the auto-destructors available.
2014 for (ty, has_destructor) in libtypes.templates_defined.borrow().iter() {
2015 write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor, None);
2017 writeln!(cpp_header_file, "}}").unwrap();
2019 header_file.flush().unwrap();
2020 cpp_header_file.flush().unwrap();
2021 derived_templates.flush().unwrap();