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" => {
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) {
167 "lightning::util::ser::Writeable" => {
168 writeln!(w, "impl {} for {} {{", trait_path, for_obj).unwrap();
169 writeln!(w, "\tfn write<W: lightning::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {{").unwrap();
170 writeln!(w, "\t\tlet vec = (self.write)(self.this_arg);").unwrap();
171 writeln!(w, "\t\tw.write_all(vec.as_slice())").unwrap();
172 writeln!(w, "\t}}\n}}").unwrap();
178 /// Returns true if an instance of the given type must never exist
179 fn is_type_unconstructable(path: &str) -> bool {
180 path == "core::convert::Infallible" || path == "crate::c_types::NotConstructable"
183 // *******************************
184 // *** Per-Type Printing Logic ***
185 // *******************************
187 macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $($pat: pat)|* => $e: expr),*) ) => { {
188 if $t.colon_token.is_some() {
189 for st in $t.supertraits.iter() {
191 syn::TypeParamBound::Trait(supertrait) => {
192 if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() {
195 // First try to resolve path to find in-crate traits, but if that doesn't work
196 // assume its a prelude trait (eg Clone, etc) and just use the single ident.
197 let types_opt: Option<&TypeResolver> = $types;
198 if let Some(types) = types_opt {
199 if let Some(path) = types.maybe_resolve_path(&supertrait.path, None) {
200 match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
201 $( $($pat)|* => $e, )*
206 if let Some(ident) = supertrait.path.get_ident() {
207 match (&format!("{}", ident) as &str, &ident) {
208 $( $($pat)|* => $e, )*
210 } else if types_opt.is_some() {
211 panic!("Supertrait unresolvable and not single-ident");
214 syn::TypeParamBound::Lifetime(_) => unimplemented!(),
220 macro_rules! get_module_type_resolver {
221 ($module: expr, $crate_libs: expr, $crate_types: expr) => { {
222 let module: &str = &$module;
223 let mut module_iter = module.rsplitn(2, "::");
224 module_iter.next().unwrap();
225 let module = module_iter.next().unwrap();
226 let imports = ImportResolver::new(module.splitn(2, "::").next().unwrap(), &$crate_types.lib_ast.dependencies,
227 module, &$crate_types.lib_ast.modules.get(module).unwrap().items);
228 TypeResolver::new(module, imports, $crate_types)
232 /// Prints a C-mapped trait object containing a void pointer and a jump table for each function in
233 /// the original trait.
234 /// Implements the native Rust trait and relevant parent traits for the new C-mapped trait.
236 /// Finally, implements Deref<MappedTrait> for MappedTrait which allows its use in types which need
237 /// a concrete Deref to the Rust trait.
238 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) {
239 let trait_name = format!("{}", t.ident);
241 match export_status(&t.attrs) {
242 ExportStatus::Export => { implementable = true; }
243 ExportStatus::NotImplementable => { implementable = false; },
244 ExportStatus::NoExport|ExportStatus::TestOnly => return,
246 writeln_docs(w, &t.attrs, "");
248 let mut gen_types = GenericTypes::new(None);
250 // Add functions which may be required for supertrait implementations.
251 // Due to borrow checker limitations, we only support one in-crate supertrait here.
253 let supertrait_resolver;
254 walk_supertraits!(t, Some(&types), (
256 if let Some(supertrait) = types.crate_types.traits.get(s) {
257 supertrait_name = s.to_string();
258 supertrait_resolver = get_module_type_resolver!(supertrait_name, types.crate_libs, types.crate_types);
259 gen_types.learn_associated_types(&supertrait, &supertrait_resolver);
265 assert!(gen_types.learn_generics(&t.generics, types));
266 gen_types.learn_associated_types(&t, types);
268 writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap();
269 writeln!(w, "\t/// An opaque pointer which is passed to your function implementations as an argument.").unwrap();
270 writeln!(w, "\t/// This has no meaning in the LDK, and can be NULL or any other value.").unwrap();
271 writeln!(w, "\tpub this_arg: *mut c_void,").unwrap();
272 // We store every field's (name, Option<clone_fn>, docs) except this_arg, used in Clone generation
273 // docs is only set if its a function which should be callable on the object itself in C++
274 let mut generated_fields = Vec::new();
275 for item in t.items.iter() {
277 &syn::TraitItem::Method(ref m) => {
278 match export_status(&m.attrs) {
279 ExportStatus::NoExport => {
280 // NoExport in this context means we'll hit an unimplemented!() at runtime,
284 ExportStatus::Export => {},
285 ExportStatus::TestOnly => continue,
286 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
288 if m.default.is_some() { unimplemented!(); }
290 let mut meth_gen_types = gen_types.push_ctx();
291 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
293 writeln_fn_docs(w, &m.attrs, "\t", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
295 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
296 if let syn::Type::Reference(r) = &**rtype {
297 // We have to do quite a dance for trait functions which return references
298 // - they ultimately require us to have a native Rust object stored inside
299 // our concrete trait to return a reference to. However, users may wish to
300 // update the value to be returned each time the function is called (or, to
301 // make C copies of Rust impls equivalent, we have to be able to).
303 // Thus, we store a copy of the C-mapped type (which is just a pointer to
304 // the Rust type and a flag to indicate whether deallocation needs to
305 // happen) as well as provide an Option<>al function pointer which is
306 // called when the trait method is called which allows updating on the fly.
307 write!(w, "\tpub {}: ", m.sig.ident).unwrap();
308 generated_fields.push((format!("{}", m.sig.ident), None, None));
309 types.write_c_type(w, &*r.elem, Some(&meth_gen_types), false);
310 writeln!(w, ",").unwrap();
311 writeln!(w, "\t/// Fill in the {} field as a reference to it will be given to Rust after this returns", m.sig.ident).unwrap();
312 writeln!(w, "\t/// Note that this takes a pointer to this object, not the this_ptr like other methods do").unwrap();
313 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();
314 writeln!(w, "\tpub set_{}: Option<extern \"C\" fn(&{})>,", m.sig.ident, trait_name).unwrap();
315 generated_fields.push((format!("set_{}", m.sig.ident), None, None));
316 // Note that cbindgen will now generate
317 // typedef struct Thing {..., set_thing: (const struct Thing*), ...} Thing;
318 // which does not compile since Thing is not defined before it is used.
319 writeln!(extra_headers, "struct LDK{};", trait_name).unwrap();
322 // Sadly, this currently doesn't do what we want, but it should be easy to get
323 // cbindgen to support it. See https://github.com/eqrion/cbindgen/issues/531
324 writeln!(w, "\t#[must_use]").unwrap();
327 let mut cpp_docs = Vec::new();
328 writeln_fn_docs(&mut cpp_docs, &m.attrs, "\t * ", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
329 let docs_string = "\t/**\n".to_owned() + &String::from_utf8(cpp_docs).unwrap().replace("///", "") + "\t */\n";
331 write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap();
332 generated_fields.push((format!("{}", m.sig.ident), None, Some(docs_string)));
333 write_method_params(w, &m.sig, "c_void", types, Some(&meth_gen_types), true, false);
334 writeln!(w, ",").unwrap();
336 &syn::TraitItem::Type(_) => {},
337 _ => unimplemented!(),
340 // Add functions which may be required for supertrait implementations.
341 walk_supertraits!(t, Some(&types), (
343 writeln!(w, "\t/// Called, if set, after this {} has been cloned into a duplicate object.", trait_name).unwrap();
344 writeln!(w, "\t/// The new {} is provided, and should be mutated as needed to perform a", trait_name).unwrap();
345 writeln!(w, "\t/// deep copy of the object pointed to by this_arg or avoid any double-freeing.").unwrap();
346 writeln!(w, "\tpub cloned: Option<extern \"C\" fn (new_{}: &mut {})>,", trait_name, trait_name).unwrap();
347 generated_fields.push(("cloned".to_owned(), None, None));
349 ("std::cmp::Eq", _)|("core::cmp::Eq", _) => {
350 let eq_docs = "Checks if two objects are equal given this object's this_arg pointer and another object.";
351 writeln!(w, "\t/// {}", eq_docs).unwrap();
352 writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap();
353 generated_fields.push(("eq".to_owned(), None, Some(format!("\t/** {} */\n", eq_docs))));
355 ("std::hash::Hash", _)|("core::hash::Hash", _) => {
356 let hash_docs_a = "Calculate a succinct non-cryptographic hash for an object given its this_arg pointer.";
357 let hash_docs_b = "This is used, for example, for inclusion of this object in a hash map.";
358 writeln!(w, "\t/// {}", hash_docs_a).unwrap();
359 writeln!(w, "\t/// {}", hash_docs_b).unwrap();
360 writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap();
361 generated_fields.push(("hash".to_owned(), None,
362 Some(format!("\t/**\n\t * {}\n\t * {}\n\t */\n", hash_docs_a, hash_docs_b))));
364 ("Send", _) => {}, ("Sync", _) => {},
365 ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
366 let debug_docs = "Return a human-readable \"debug\" string describing this object";
367 writeln!(w, "\t/// {}", debug_docs).unwrap();
368 writeln!(w, "\tpub debug_str: extern \"C\" fn (this_arg: *const c_void) -> crate::c_types::Str,").unwrap();
369 generated_fields.push(("debug_str".to_owned(), None,
370 Some(format!("\t/**\n\t * {}\n\t */\n", debug_docs))));
373 // TODO: Both of the below should expose supertrait methods in C++, but doing so is
375 generated_fields.push(if types.crate_types.traits.get(s).is_none() {
376 let (docs, name, ret) = convert_trait_impl_field(s);
377 writeln!(w, "\t/// {}", docs).unwrap();
378 writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap();
379 (name, None, None) // Assume clonable
381 // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
382 writeln!(w, "\t/// Implementation of {} for this object.", i).unwrap();
383 let is_clonable = types.is_clonable(s);
384 writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
385 (format!("{}", i), if !is_clonable {
386 Some(format!("crate::{}_clone_fields", s))
387 } else { None }, None)
391 writeln!(w, "\t/// Frees any resources associated with this object given its this_arg pointer.").unwrap();
392 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();
393 writeln!(w, "\tpub free: Option<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
394 generated_fields.push(("free".to_owned(), None, None));
395 writeln!(w, "}}").unwrap();
397 macro_rules! impl_trait_for_c {
398 ($t: expr, $impl_accessor: expr, $type_resolver: expr) => {
399 for item in $t.items.iter() {
401 syn::TraitItem::Method(m) => {
402 if let ExportStatus::TestOnly = export_status(&m.attrs) { continue; }
403 if m.default.is_some() { unimplemented!(); }
404 if m.sig.constness.is_some() || m.sig.asyncness.is_some() || m.sig.unsafety.is_some() ||
405 m.sig.abi.is_some() || m.sig.variadic.is_some() {
408 let mut meth_gen_types = gen_types.push_ctx();
409 assert!(meth_gen_types.learn_generics(&m.sig.generics, $type_resolver));
410 // Note that we do *not* use the method generics when printing "native"
411 // rust parts - if the method is generic, we need to print a generic
413 write!(w, "\tfn {}", m.sig.ident).unwrap();
414 $type_resolver.write_rust_generic_param(w, Some(&gen_types), m.sig.generics.params.iter());
415 write!(w, "(").unwrap();
416 for inp in m.sig.inputs.iter() {
418 syn::FnArg::Receiver(recv) => {
419 if !recv.attrs.is_empty() || recv.reference.is_none() { unimplemented!(); }
420 write!(w, "&").unwrap();
421 if let Some(lft) = &recv.reference.as_ref().unwrap().1 {
422 write!(w, "'{} ", lft.ident).unwrap();
424 if recv.mutability.is_some() {
425 write!(w, "mut self").unwrap();
427 write!(w, "self").unwrap();
430 syn::FnArg::Typed(arg) => {
431 if !arg.attrs.is_empty() { unimplemented!(); }
433 syn::Pat::Ident(ident) => {
434 if !ident.attrs.is_empty() || ident.by_ref.is_some() ||
435 ident.mutability.is_some() || ident.subpat.is_some() {
438 write!(w, ", mut {}{}: ", if $type_resolver.skip_arg(&*arg.ty, Some(&meth_gen_types)) { "_" } else { "" }, ident.ident).unwrap();
440 _ => unimplemented!(),
442 $type_resolver.write_rust_type(w, Some(&gen_types), &*arg.ty);
446 write!(w, ")").unwrap();
447 match &m.sig.output {
448 syn::ReturnType::Type(_, rtype) => {
449 write!(w, " -> ").unwrap();
450 $type_resolver.write_rust_type(w, Some(&gen_types), &*rtype)
454 write!(w, " {{\n\t\t").unwrap();
455 match export_status(&m.attrs) {
456 ExportStatus::NoExport => {
461 if let syn::ReturnType::Type(_, rtype) = &m.sig.output {
462 if let syn::Type::Reference(r) = &**rtype {
463 assert_eq!(m.sig.inputs.len(), 1); // Must only take self!
464 writeln!(w, "if let Some(f) = self{}.set_{} {{", $impl_accessor, m.sig.ident).unwrap();
465 writeln!(w, "\t\t\t(f)(&self{});", $impl_accessor).unwrap();
466 write!(w, "\t\t}}\n\t\t").unwrap();
467 $type_resolver.write_from_c_conversion_to_ref_prefix(w, &*r.elem, Some(&meth_gen_types));
468 write!(w, "self{}.{}", $impl_accessor, m.sig.ident).unwrap();
469 $type_resolver.write_from_c_conversion_to_ref_suffix(w, &*r.elem, Some(&meth_gen_types));
470 writeln!(w, "\n\t}}").unwrap();
474 write_method_var_decl_body(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), true);
475 write!(w, "(self{}.{})(", $impl_accessor, m.sig.ident).unwrap();
476 let mut args = Vec::new();
477 write_method_call_params(&mut args, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), "", true);
478 w.write_all(String::from_utf8(args).unwrap().replace("self", &format!("self{}", $impl_accessor)).as_bytes()).unwrap();
480 writeln!(w, "\n\t}}").unwrap();
482 &syn::TraitItem::Type(ref t) => {
483 if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); }
484 let mut bounds_iter = t.bounds.iter();
485 match bounds_iter.next().unwrap() {
486 syn::TypeParamBound::Trait(tr) => {
487 writeln!(w, "\ttype {} = crate::{};", t.ident, $type_resolver.resolve_path(&tr.path, Some(&gen_types))).unwrap();
489 _ => unimplemented!(),
491 if bounds_iter.next().is_some() { unimplemented!(); }
493 _ => unimplemented!(),
499 writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap();
500 writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap();
502 writeln!(w, "#[no_mangle]").unwrap();
503 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_fields(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
504 writeln!(w, "\t{} {{", trait_name).unwrap();
505 writeln!(w, "\t\tthis_arg: orig.this_arg,").unwrap();
506 for (field, clone_fn, _) in generated_fields.iter() {
507 if let Some(f) = clone_fn {
508 // If the field isn't clonable, blindly assume its a trait and hope for the best.
509 writeln!(w, "\t\t{}: {}(&orig.{}),", field, f, field).unwrap();
511 writeln!(w, "\t\t{}: Clone::clone(&orig.{}),", field, field).unwrap();
514 writeln!(w, "\t}}\n}}").unwrap();
516 // Implement supertraits for the C-mapped struct.
517 walk_supertraits!(t, Some(&types), (
518 ("std::cmp::Eq", _)|("core::cmp::Eq", _) => {
519 writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap();
520 writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap();
521 writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o) }}\n}}").unwrap();
523 ("std::hash::Hash", _)|("core::hash::Hash", _) => {
524 writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap();
525 writeln!(w, "\tfn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap();
527 ("Send", _) => {}, ("Sync", _) => {},
529 writeln!(w, "#[no_mangle]").unwrap();
530 writeln!(w, "/// Creates a copy of a {}", trait_name).unwrap();
531 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap();
532 writeln!(w, "\tlet mut res = {}_clone_fields(orig);", trait_name).unwrap();
533 writeln!(w, "\tif let Some(f) = orig.cloned {{ (f)(&mut res) }};").unwrap();
534 writeln!(w, "\tres\n}}").unwrap();
535 writeln!(w, "impl Clone for {} {{", trait_name).unwrap();
536 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
537 writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap();
538 writeln!(w, "\t}}\n}}").unwrap();
540 ("std::fmt::Debug", _)|("core::fmt::Debug", _) => {
541 writeln!(w, "impl core::fmt::Debug for {} {{", trait_name).unwrap();
542 writeln!(w, "\tfn fmt(&self, f: &mut core::fmt::Formatter) -> Result<(), core::fmt::Error> {{").unwrap();
543 writeln!(w, "\t\tf.write_str((self.debug_str)(self.this_arg).into_str())").unwrap();
544 writeln!(w, "\t}}").unwrap();
545 writeln!(w, "}}").unwrap();
548 if let Some(supertrait) = types.crate_types.traits.get(s) {
549 let resolver = get_module_type_resolver!(s, types.crate_libs, types.crate_types);
550 writeln!(w, "impl {} for {} {{", s, trait_name).unwrap();
551 impl_trait_for_c!(supertrait, format!(".{}", i), &resolver);
552 writeln!(w, "}}").unwrap();
554 do_write_impl_trait(w, s, i, &trait_name);
559 // Finally, implement the original Rust trait for the newly created mapped trait.
560 writeln!(w, "\nuse {}::{} as rust{};", types.module_path, t.ident, trait_name).unwrap();
562 write!(w, "impl").unwrap();
563 maybe_write_lifetime_generics(w, &t.generics, types);
564 write!(w, " rust{}", t.ident).unwrap();
565 maybe_write_generics(w, &t.generics, types, false);
566 writeln!(w, " for {} {{", trait_name).unwrap();
567 impl_trait_for_c!(t, "", types);
568 writeln!(w, "}}\n").unwrap();
569 writeln!(w, "// We're essentially a pointer already, or at least a set of pointers, so allow us to be used").unwrap();
570 writeln!(w, "// directly as a Deref trait in higher-level structs:").unwrap();
571 writeln!(w, "impl std::ops::Deref for {} {{\n\ttype Target = Self;", trait_name).unwrap();
572 writeln!(w, "\tfn deref(&self) -> &Self {{\n\t\tself\n\t}}\n}}").unwrap();
575 writeln!(w, "/// Calls the free function if one is set").unwrap();
576 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", trait_name, trait_name).unwrap();
577 writeln!(w, "impl Drop for {} {{", trait_name).unwrap();
578 writeln!(w, "\tfn drop(&mut self) {{").unwrap();
579 writeln!(w, "\t\tif let Some(f) = self.free {{").unwrap();
580 writeln!(w, "\t\t\tf(self.this_arg);").unwrap();
581 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
583 write_cpp_wrapper(cpp_headers, &trait_name, true, Some(generated_fields.drain(..)
584 .filter_map(|(name, _, docs)| if let Some(docs) = docs { Some((name, docs)) } else { None }).collect()));
587 /// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type
588 /// and a flag to indicate whether Drop'ing the mapped struct drops the underlying Rust type.
590 /// Also writes out a _free function and a C++ wrapper which handles calling _free.
591 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) {
592 // If we directly read the original type by its original name, cbindgen hits
593 // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary
594 // name and then reference it by that name, which works around the issue.
595 write!(w, "\nuse {}::{} as native{}Import;\npub(crate) type native{} = native{}Import", types.module_path, ident, ident, ident, ident).unwrap();
596 maybe_write_generics(w, &generics, &types, true);
597 writeln!(w, ";\n").unwrap();
598 writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap();
599 writeln_docs(w, &attrs, "");
600 writeln!(w, "#[must_use]\n#[repr(C)]\npub struct {} {{", struct_name).unwrap();
601 writeln!(w, "\t/// A pointer to the opaque Rust object.\n").unwrap();
602 writeln!(w, "\t/// Nearly everywhere, inner must be non-null, however in places where").unwrap();
603 writeln!(w, "\t/// the Rust equivalent takes an Option, it may be set to null to indicate None.").unwrap();
604 writeln!(w, "\tpub inner: *mut native{},", ident).unwrap();
605 writeln!(w, "\t/// Indicates that this is the only struct which contains the same pointer.\n").unwrap();
606 writeln!(w, "\t/// Rust functions which take ownership of an object provided via an argument require").unwrap();
607 writeln!(w, "\t/// this to be true and invalidate the object pointed to by inner.").unwrap();
608 writeln!(w, "\tpub is_owned: bool,").unwrap();
609 writeln!(w, "}}\n").unwrap();
610 writeln!(w, "impl Drop for {} {{\n\tfn drop(&mut self) {{", struct_name).unwrap();
611 writeln!(w, "\t\tif self.is_owned && !<*mut native{}>::is_null(self.inner) {{", ident).unwrap();
612 writeln!(w, "\t\t\tlet _ = unsafe {{ Box::from_raw(ObjOps::untweak_ptr(self.inner)) }};\n\t\t}}\n\t}}\n}}").unwrap();
613 writeln!(w, "/// Frees any resources used by the {}, if is_owned is set and inner is non-NULL.", struct_name).unwrap();
614 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_obj: {}) {{ }}", struct_name, struct_name).unwrap();
615 writeln!(w, "#[allow(unused)]").unwrap();
616 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
617 writeln!(w, "pub(crate) extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
618 writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap();
619 writeln!(w, "#[allow(unused)]").unwrap();
620 writeln!(w, "impl {} {{", struct_name).unwrap();
621 writeln!(w, "\tpub(crate) fn get_native_ref(&self) -> &'static native{} {{", struct_name).unwrap();
622 writeln!(w, "\t\tunsafe {{ &*ObjOps::untweak_ptr(self.inner) }}").unwrap();
623 writeln!(w, "\t}}").unwrap();
624 writeln!(w, "\tpub(crate) fn get_native_mut_ref(&self) -> &'static mut native{} {{", struct_name).unwrap();
625 writeln!(w, "\t\tunsafe {{ &mut *ObjOps::untweak_ptr(self.inner) }}").unwrap();
626 writeln!(w, "\t}}").unwrap();
627 writeln!(w, "\t/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap();
628 writeln!(w, "\tpub(crate) fn take_inner(mut self) -> *mut native{} {{", struct_name).unwrap();
629 writeln!(w, "\t\tassert!(self.is_owned);").unwrap();
630 writeln!(w, "\t\tlet ret = ObjOps::untweak_ptr(self.inner);").unwrap();
631 writeln!(w, "\t\tself.inner = std::ptr::null_mut();").unwrap();
632 writeln!(w, "\t\tret").unwrap();
633 writeln!(w, "\t}}\n}}").unwrap();
635 write_cpp_wrapper(cpp_headers, &format!("{}", ident), true, None);
638 /// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
639 /// the struct itself, and then writing getters and setters for public, understood-type fields and
640 /// a constructor if every field is public.
641 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) {
642 if export_status(&s.attrs) != ExportStatus::Export { return; }
644 let struct_name = &format!("{}", s.ident);
645 writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers);
647 if let syn::Fields::Named(fields) = &s.fields {
648 let mut self_path_segs = syn::punctuated::Punctuated::new();
649 self_path_segs.push(s.ident.clone().into());
650 let self_path = syn::Path { leading_colon: None, segments: self_path_segs};
651 let mut gen_types = GenericTypes::new(Some(types.resolve_path(&self_path, None)));
652 assert!(gen_types.learn_generics(&s.generics, types));
654 let mut all_fields_settable = true;
655 for field in fields.named.iter() {
656 if let syn::Visibility::Public(_) = field.vis {
657 let export = export_status(&field.attrs);
659 ExportStatus::Export => {},
660 ExportStatus::NoExport|ExportStatus::TestOnly => {
661 all_fields_settable = false;
664 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
667 if let Some(ident) = &field.ident {
668 if let Some(ref_type) = types.create_ownable_reference(&field.ty, Some(&gen_types)) {
669 if types.understood_c_type(&ref_type, Some(&gen_types)) {
670 writeln_arg_docs(w, &field.attrs, "", types, Some(&gen_types), vec![].drain(..), Some(&ref_type));
671 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_get_{}(this_ptr: &{}) -> ", struct_name, ident, struct_name).unwrap();
672 types.write_c_type(w, &ref_type, Some(&gen_types), true);
673 write!(w, " {{\n\tlet mut inner_val = &mut this_ptr.get_native_mut_ref().{};\n\t", ident).unwrap();
674 let local_var = types.write_to_c_conversion_new_var(w, &format_ident!("inner_val"), &ref_type, Some(&gen_types), true);
675 if local_var { write!(w, "\n\t").unwrap(); }
676 types.write_to_c_conversion_inline_prefix(w, &ref_type, Some(&gen_types), true);
677 write!(w, "inner_val").unwrap();
678 types.write_to_c_conversion_inline_suffix(w, &ref_type, Some(&gen_types), true);
679 writeln!(w, "\n}}").unwrap();
683 if types.understood_c_type(&field.ty, Some(&gen_types)) {
684 writeln_arg_docs(w, &field.attrs, "", types, Some(&gen_types), vec![("val".to_owned(), &field.ty)].drain(..), None);
685 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_set_{}(this_ptr: &mut {}, mut val: ", struct_name, ident, struct_name).unwrap();
686 types.write_c_type(w, &field.ty, Some(&gen_types), false);
687 write!(w, ") {{\n\t").unwrap();
688 let local_var = types.write_from_c_conversion_new_var(w, &format_ident!("val"), &field.ty, Some(&gen_types));
689 if local_var { write!(w, "\n\t").unwrap(); }
690 write!(w, "unsafe {{ &mut *ObjOps::untweak_ptr(this_ptr.inner) }}.{} = ", ident).unwrap();
691 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
692 write!(w, "val").unwrap();
693 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
694 writeln!(w, ";\n}}").unwrap();
695 } else { all_fields_settable = false; }
696 } else { all_fields_settable = false; }
697 } else { all_fields_settable = false; }
700 if all_fields_settable {
701 // Build a constructor!
702 writeln!(w, "/// Constructs a new {} given each field", struct_name).unwrap();
703 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_new(", struct_name).unwrap();
704 for (idx, field) in fields.named.iter().enumerate() {
705 if idx != 0 { write!(w, ", ").unwrap(); }
706 write!(w, "mut {}_arg: ", field.ident.as_ref().unwrap()).unwrap();
707 types.write_c_type(w, &field.ty, Some(&gen_types), false);
709 write!(w, ") -> {} {{\n\t", struct_name).unwrap();
710 for field in fields.named.iter() {
711 let field_ident = format_ident!("{}_arg", field.ident.as_ref().unwrap());
712 if types.write_from_c_conversion_new_var(w, &field_ident, &field.ty, Some(&gen_types)) {
713 write!(w, "\n\t").unwrap();
716 writeln!(w, "{} {{ inner: ObjOps::heap_alloc(native{} {{", struct_name, s.ident).unwrap();
717 for field in fields.named.iter() {
718 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
719 types.write_from_c_conversion_prefix(w, &field.ty, Some(&gen_types));
720 write!(w, "{}_arg", field.ident.as_ref().unwrap()).unwrap();
721 types.write_from_c_conversion_suffix(w, &field.ty, Some(&gen_types));
722 writeln!(w, ",").unwrap();
724 writeln!(w, "\t}}), is_owned: true }}\n}}").unwrap();
729 /// Prints a relevant conversion for impl *
731 /// For simple impl Struct {}s, this just outputs the wrapper functions as Struct_fn_name() { .. }.
733 /// For impl Trait for Struct{}s, this non-exported generates wrapper functions as
734 /// Trait_Struct_fn_name and a Struct_as_Trait(&struct) -> Trait function which returns a populated
735 /// Trait struct containing a pointer to the passed struct's inner field and the wrapper functions.
737 /// A few non-crate Traits are hard-coded including Default.
738 fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) {
739 match export_status(&i.attrs) {
740 ExportStatus::Export => {},
741 ExportStatus::NoExport|ExportStatus::TestOnly => return,
742 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
745 if let syn::Type::Tuple(_) = &*i.self_ty {
746 if types.understood_c_type(&*i.self_ty, None) {
747 let mut gen_types = GenericTypes::new(None);
748 if !gen_types.learn_generics(&i.generics, types) {
749 eprintln!("Not implementing anything for `impl (..)` due to not understood generics");
753 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
754 if let Some(trait_path) = i.trait_.as_ref() {
755 if trait_path.0.is_some() { unimplemented!(); }
756 if types.understood_c_path(&trait_path.1) {
757 eprintln!("Not implementing anything for `impl Trait for (..)` - we only support manual defines");
760 // Just do a manual implementation:
761 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
764 eprintln!("Not implementing anything for plain `impl (..)` block - we only support `impl Trait for (..)` blocks");
770 if let &syn::Type::Path(ref p) = &*i.self_ty {
771 if p.qself.is_some() { unimplemented!(); }
772 if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
773 if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) {
774 let mut gen_types = GenericTypes::new(Some(resolved_path.clone()));
775 if !gen_types.learn_generics(&i.generics, types) {
776 eprintln!("Not implementing anything for impl {} due to not understood generics", ident);
780 if i.defaultness.is_some() || i.unsafety.is_some() { unimplemented!(); }
781 if let Some(trait_path) = i.trait_.as_ref() {
782 if trait_path.0.is_some() { unimplemented!(); }
783 if types.understood_c_path(&trait_path.1) {
784 let full_trait_path = types.resolve_path(&trait_path.1, None);
785 let trait_obj = *types.crate_types.traits.get(&full_trait_path).unwrap();
788 let supertrait_resolver;
789 walk_supertraits!(trait_obj, Some(&types), (
791 if let Some(supertrait) = types.crate_types.traits.get(s) {
792 supertrait_name = s.to_string();
793 supertrait_resolver = get_module_type_resolver!(supertrait_name, types.crate_libs, types.crate_types);
794 gen_types.learn_associated_types(&supertrait, &supertrait_resolver);
799 // We learn the associated types maping from the original trait object.
800 // That's great, except that they are unresolved idents, so if we learn
801 // mappings from a trai defined in a different file, we may mis-resolve or
802 // fail to resolve the mapped types. Thus, we have to construct a new
803 // resolver for the module that the trait was defined in here first.
804 let trait_resolver = get_module_type_resolver!(full_trait_path, types.crate_libs, types.crate_types);
805 gen_types.learn_associated_types(trait_obj, &trait_resolver);
806 let mut impl_associated_types = HashMap::new();
807 for item in i.items.iter() {
809 syn::ImplItem::Type(t) => {
810 if let syn::Type::Path(p) = &t.ty {
811 if let Some(id) = single_ident_generic_path_to_ident(&p.path) {
812 impl_associated_types.insert(&t.ident, id);
820 let export = export_status(&trait_obj.attrs);
822 ExportStatus::Export|ExportStatus::NotImplementable => {},
823 ExportStatus::NoExport|ExportStatus::TestOnly => return,
826 // For cases where we have a concrete native object which implements a
827 // trait and need to return the C-mapped version of the trait, provide a
828 // From<> implementation which does all the work to ensure free is handled
829 // properly. This way we can call this method from deep in the
830 // type-conversion logic without actually knowing the concrete native type.
831 if !resolved_path.starts_with(types.module_path) {
832 if !first_seg_is_stdlib(resolved_path.split("::").next().unwrap()) {
833 writeln!(w, "use crate::{}::native{} as native{};", resolved_path.rsplitn(2, "::").skip(1).next().unwrap(), ident, ident).unwrap();
834 writeln!(w, "use crate::{};", resolved_path).unwrap();
835 writeln!(w, "use crate::{}_free_void;", resolved_path).unwrap();
837 writeln!(w, "use {} as native{};", resolved_path, ident).unwrap();
840 writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
841 writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();
842 if is_type_unconstructable(&resolved_path) {
843 writeln!(w, "\t\tunreachable!();").unwrap();
845 writeln!(w, "\t\tlet mut rust_obj = {} {{ inner: ObjOps::heap_alloc(obj), is_owned: true }};", ident).unwrap();
846 writeln!(w, "\t\tlet mut ret = {}_as_{}(&rust_obj);", ident, trait_obj.ident).unwrap();
847 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();
848 writeln!(w, "\t\trust_obj.inner = std::ptr::null_mut();").unwrap();
849 writeln!(w, "\t\tret.free = Some({}_free_void);", ident).unwrap();
850 writeln!(w, "\t\tret").unwrap();
852 writeln!(w, "\t}}\n}}").unwrap();
853 if is_type_unconstructable(&resolved_path) {
854 // We don't bother with Struct_as_Trait conversion for types which must
855 // never be instantiated, so just return early.
859 writeln!(w, "/// Constructs a new {} which calls the relevant methods on this_arg.", trait_obj.ident).unwrap();
860 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();
861 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: &{}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
862 writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
863 writeln!(w, "\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},").unwrap();
864 writeln!(w, "\t\tfree: None,").unwrap();
866 macro_rules! write_meth {
867 ($m: expr, $trait: expr, $indent: expr) => {
868 let trait_method = $trait.items.iter().filter_map(|item| {
869 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
870 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
871 match export_status(&trait_method.attrs) {
872 ExportStatus::Export => {},
873 ExportStatus::NoExport => {
874 write!(w, "{}\t\t//XXX: Need to export {}\n", $indent, $m.sig.ident).unwrap();
877 ExportStatus::TestOnly => continue,
878 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
881 let mut printed = false;
882 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
883 if let syn::Type::Reference(r) = &**rtype {
884 write!(w, "\n\t\t{}{}: ", $indent, $m.sig.ident).unwrap();
885 types.write_empty_rust_val(Some(&gen_types), w, &*r.elem);
886 writeln!(w, ",\n{}\t\tset_{}: Some({}_{}_set_{}),", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
891 write!(w, "{}\t\t{}: {}_{}_{},\n", $indent, $m.sig.ident, ident, $trait.ident, $m.sig.ident).unwrap();
895 for item in trait_obj.items.iter() {
897 syn::TraitItem::Method(m) => {
898 write_meth!(m, trait_obj, "");
903 let mut requires_clone = false;
904 walk_supertraits!(trait_obj, Some(&types), (
906 requires_clone = true;
907 writeln!(w, "\t\tcloned: Some({}_{}_cloned),", trait_obj.ident, ident).unwrap();
909 ("Sync", _) => {}, ("Send", _) => {},
910 ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
911 ("core::fmt::Debug", _) => {},
913 if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
914 writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();
915 writeln!(w, "\t\t\tthis_arg: unsafe {{ ObjOps::untweak_ptr((*this_arg).inner) as *mut c_void }},").unwrap();
916 writeln!(w, "\t\t\tfree: None,").unwrap();
917 for item in supertrait_obj.items.iter() {
919 syn::TraitItem::Method(m) => {
920 write_meth!(m, supertrait_obj, "\t");
925 write!(w, "\t\t}},\n").unwrap();
927 write_trait_impl_field_assign(w, s, ident);
931 writeln!(w, "\t}}\n}}\n").unwrap();
933 macro_rules! impl_meth {
934 ($m: expr, $trait_meth: expr, $trait_path: expr, $trait: expr, $indent: expr) => {
935 let trait_method = $trait.items.iter().filter_map(|item| {
936 if let syn::TraitItem::Method(t_m) = item { Some(t_m) } else { None }
937 }).find(|trait_meth| trait_meth.sig.ident == $m.sig.ident).unwrap();
938 match export_status(&trait_method.attrs) {
939 ExportStatus::Export => {},
940 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
941 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
944 if let syn::ReturnType::Type(_, _) = &$m.sig.output {
945 writeln!(w, "#[must_use]").unwrap();
947 write!(w, "extern \"C\" fn {}_{}_{}(", ident, $trait.ident, $m.sig.ident).unwrap();
948 let mut meth_gen_types = gen_types.push_ctx();
949 assert!(meth_gen_types.learn_generics(&$m.sig.generics, types));
950 let mut uncallable_function = false;
951 for inp in $m.sig.inputs.iter() {
953 syn::FnArg::Typed(arg) => {
954 if types.skip_arg(&*arg.ty, Some(&meth_gen_types)) { continue; }
955 let mut c_type = Vec::new();
956 types.write_c_type(&mut c_type, &*arg.ty, Some(&meth_gen_types), false);
957 if is_type_unconstructable(&String::from_utf8(c_type).unwrap()) {
958 uncallable_function = true;
964 if uncallable_function {
965 let mut trait_resolver = get_module_type_resolver!(full_trait_path, types.crate_libs, types.crate_types);
966 write_method_params(w, &$trait_meth.sig, "c_void", &mut trait_resolver, Some(&meth_gen_types), true, true);
968 write_method_params(w, &$m.sig, "c_void", types, Some(&meth_gen_types), true, true);
970 write!(w, " {{\n\t").unwrap();
971 if uncallable_function {
972 write!(w, "unreachable!();").unwrap();
974 write_method_var_decl_body(w, &$m.sig, "", types, Some(&meth_gen_types), false);
975 let mut takes_self = false;
976 for inp in $m.sig.inputs.iter() {
977 if let syn::FnArg::Receiver(_) = inp {
982 let mut t_gen_args = String::new();
983 for (idx, _) in $trait.generics.params.iter().enumerate() {
984 if idx != 0 { t_gen_args += ", " };
988 write!(w, "<native{} as {}<{}>>::{}(unsafe {{ &mut *(this_arg as *mut native{}) }}, ", ident, $trait_path, t_gen_args, $m.sig.ident, ident).unwrap();
990 write!(w, "<native{} as {}<{}>>::{}(", ident, $trait_path, t_gen_args, $m.sig.ident).unwrap();
993 let mut real_type = "".to_string();
994 match &$m.sig.output {
995 syn::ReturnType::Type(_, rtype) => {
996 if let Some(mut remaining_path) = first_seg_self(&*rtype) {
997 if let Some(associated_seg) = get_single_remaining_path_seg(&mut remaining_path) {
998 real_type = format!("{}", impl_associated_types.get(associated_seg).unwrap());
1004 write_method_call_params(w, &$m.sig, "", types, Some(&meth_gen_types), &real_type, false);
1006 write!(w, "\n}}\n").unwrap();
1007 if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
1008 if let syn::Type::Reference(r) = &**rtype {
1009 assert_eq!($m.sig.inputs.len(), 1); // Must only take self
1010 writeln!(w, "extern \"C\" fn {}_{}_set_{}(trait_self_arg: &{}) {{", ident, $trait.ident, $m.sig.ident, $trait.ident).unwrap();
1011 writeln!(w, "\t// This is a bit race-y in the general case, but for our specific use-cases today, we're safe").unwrap();
1012 writeln!(w, "\t// Specifically, we must ensure that the first time we're called it can never be in parallel").unwrap();
1013 write!(w, "\tif ").unwrap();
1014 types.write_empty_rust_val_check(Some(&meth_gen_types), w, &*r.elem, &format!("trait_self_arg.{}", $m.sig.ident));
1015 writeln!(w, " {{").unwrap();
1016 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();
1017 writeln!(w, "\t}}").unwrap();
1018 writeln!(w, "}}").unwrap();
1024 'impl_item_loop: for item in i.items.iter() {
1026 syn::ImplItem::Method(m) => {
1027 for trait_item in trait_obj.items.iter() {
1029 syn::TraitItem::Method(meth) => {
1030 if meth.sig.ident == m.sig.ident {
1031 impl_meth!(m, meth, full_trait_path, trait_obj, "");
1032 continue 'impl_item_loop;
1040 syn::ImplItem::Type(_) => {},
1041 _ => unimplemented!(),
1045 writeln!(w, "extern \"C\" fn {}_{}_cloned(new_obj: &mut crate::{}) {{", trait_obj.ident, ident, full_trait_path).unwrap();
1046 writeln!(w, "\tnew_obj.this_arg = {}_clone_void(new_obj.this_arg);", ident).unwrap();
1047 writeln!(w, "\tnew_obj.free = Some({}_free_void);", ident).unwrap();
1048 walk_supertraits!(trait_obj, Some(&types), (
1050 if types.crate_types.traits.get(s).is_some() {
1051 assert!(!types.is_clonable(s)); // We don't currently support cloning with a clonable supertrait
1052 writeln!(w, "\tnew_obj.{}.this_arg = new_obj.this_arg;", t).unwrap();
1053 writeln!(w, "\tnew_obj.{}.free = None;", t).unwrap();
1057 writeln!(w, "}}").unwrap();
1059 write!(w, "\n").unwrap();
1062 if is_type_unconstructable(&resolved_path) {
1063 // Don't bother exposing trait implementations for objects which cannot be
1067 if path_matches_nongeneric(&trait_path.1, &["From"]) {
1068 } else if path_matches_nongeneric(&trait_path.1, &["Default"]) {
1069 writeln!(w, "/// Creates a \"default\" {}. See struct and individual field documentaiton for details on which values are used.", ident).unwrap();
1070 write!(w, "#[must_use]\n#[no_mangle]\npub extern \"C\" fn {}_default() -> {} {{\n", ident, ident).unwrap();
1071 write!(w, "\t{} {{ inner: ObjOps::heap_alloc(Default::default()), is_owned: true }}\n", ident).unwrap();
1072 write!(w, "}}\n").unwrap();
1073 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "PartialEq"]) {
1074 } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "Eq"]) {
1075 writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap();
1076 writeln!(w, "/// This ignores pointers and is_owned flags and looks at the values in fields.").unwrap();
1077 if types.c_type_has_inner_from_path(&resolved_path) {
1078 writeln!(w, "/// Two objects with NULL inner values will be considered \"equal\" here.").unwrap();
1080 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_eq(a: &{}, b: &{}) -> bool {{\n", ident, ident, ident).unwrap();
1081 if types.c_type_has_inner_from_path(&resolved_path) {
1082 write!(w, "\tif a.inner == b.inner {{ return true; }}\n").unwrap();
1083 write!(w, "\tif a.inner.is_null() || b.inner.is_null() {{ return false; }}\n").unwrap();
1087 let ref_type: syn::Type = syn::parse_quote!(&#path);
1088 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");
1090 write!(w, "\tif ").unwrap();
1091 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1092 write!(w, "a").unwrap();
1093 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1094 write!(w, " == ").unwrap();
1095 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1096 write!(w, "b").unwrap();
1097 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1099 writeln!(w, " {{ true }} else {{ false }}\n}}").unwrap();
1100 } else if path_matches_nongeneric(&trait_path.1, &["core", "hash", "Hash"]) {
1101 writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap();
1102 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_hash(o: &{}) -> u64 {{\n", ident, ident).unwrap();
1103 if types.c_type_has_inner_from_path(&resolved_path) {
1104 write!(w, "\tif o.inner.is_null() {{ return 0; }}\n").unwrap();
1108 let ref_type: syn::Type = syn::parse_quote!(&#path);
1109 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");
1111 writeln!(w, "\t// Note that we'd love to use std::collections::hash_map::DefaultHasher but it's not in core").unwrap();
1112 writeln!(w, "\t#[allow(deprecated)]").unwrap();
1113 writeln!(w, "\tlet mut hasher = core::hash::SipHasher::new();").unwrap();
1114 write!(w, "\tstd::hash::Hash::hash(").unwrap();
1115 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1116 write!(w, "o").unwrap();
1117 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1118 writeln!(w, ", &mut hasher);").unwrap();
1119 writeln!(w, "\tstd::hash::Hasher::finish(&hasher)\n}}").unwrap();
1120 } else if (path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) || path_matches_nongeneric(&trait_path.1, &["Clone"])) &&
1121 types.c_type_has_inner_from_path(&resolved_path) {
1122 writeln!(w, "impl Clone for {} {{", ident).unwrap();
1123 writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
1124 writeln!(w, "\t\tSelf {{").unwrap();
1125 writeln!(w, "\t\t\tinner: if <*mut native{}>::is_null(self.inner) {{ std::ptr::null_mut() }} else {{", ident).unwrap();
1126 writeln!(w, "\t\t\t\tObjOps::heap_alloc(unsafe {{ &*ObjOps::untweak_ptr(self.inner) }}.clone()) }},").unwrap();
1127 writeln!(w, "\t\t\tis_owned: true,").unwrap();
1128 writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
1129 writeln!(w, "#[allow(unused)]").unwrap();
1130 writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
1131 writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", ident).unwrap();
1132 writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", ident).unwrap();
1133 writeln!(w, "}}").unwrap();
1134 writeln!(w, "#[no_mangle]").unwrap();
1135 writeln!(w, "/// Creates a copy of the {}", ident).unwrap();
1136 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", ident, ident, ident).unwrap();
1137 writeln!(w, "\torig.clone()").unwrap();
1138 writeln!(w, "}}").unwrap();
1139 } else if path_matches_nongeneric(&trait_path.1, &["FromStr"]) {
1140 if let Some(container) = types.get_c_mangled_container_type(
1141 vec![&*i.self_ty, &syn::Type::Tuple(syn::TypeTuple { paren_token: Default::default(), elems: syn::punctuated::Punctuated::new() })],
1142 Some(&gen_types), "Result") {
1143 writeln!(w, "#[no_mangle]").unwrap();
1144 writeln!(w, "/// Read a {} object from a string", ident).unwrap();
1145 writeln!(w, "pub extern \"C\" fn {}_from_str(s: crate::c_types::Str) -> {} {{", ident, container).unwrap();
1146 writeln!(w, "\tmatch {}::from_str(s.into_str()) {{", resolved_path).unwrap();
1147 writeln!(w, "\t\tOk(r) => {{").unwrap();
1148 let new_var = types.write_to_c_conversion_new_var(w, &format_ident!("r"), &*i.self_ty, Some(&gen_types), false);
1149 write!(w, "\t\t\tcrate::c_types::CResultTempl::ok(\n\t\t\t\t").unwrap();
1150 types.write_to_c_conversion_inline_prefix(w, &*i.self_ty, Some(&gen_types), false);
1151 write!(w, "{}r", if new_var { "local_" } else { "" }).unwrap();
1152 types.write_to_c_conversion_inline_suffix(w, &*i.self_ty, Some(&gen_types), false);
1153 writeln!(w, "\n\t\t\t)\n\t\t}},").unwrap();
1154 writeln!(w, "\t\tErr(e) => crate::c_types::CResultTempl::err(()),").unwrap();
1155 writeln!(w, "\t}}.into()\n}}").unwrap();
1157 } else if path_matches_nongeneric(&trait_path.1, &["Display"]) {
1158 writeln!(w, "#[no_mangle]").unwrap();
1159 writeln!(w, "/// Get the string representation of a {} object", ident).unwrap();
1160 writeln!(w, "pub extern \"C\" fn {}_to_str(o: &crate::{}) -> Str {{", ident, resolved_path).unwrap();
1162 let self_ty = &i.self_ty;
1163 let ref_type: syn::Type = syn::parse_quote!(&#self_ty);
1164 let new_var = types.write_from_c_conversion_new_var(w, &format_ident!("o"), &ref_type, Some(&gen_types));
1165 write!(w, "\tformat!(\"{{}}\", ").unwrap();
1166 types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types));
1167 write!(w, "{}o", if new_var { "local_" } else { "" }).unwrap();
1168 types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types));
1169 writeln!(w, ").into()").unwrap();
1171 writeln!(w, "}}").unwrap();
1173 //XXX: implement for other things like ToString
1174 // If we have no generics, try a manual implementation:
1175 maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
1178 let declared_type = (*types.get_declared_type(&ident).unwrap()).clone();
1179 for item in i.items.iter() {
1181 syn::ImplItem::Method(m) => {
1182 if let syn::Visibility::Public(_) = m.vis {
1183 match export_status(&m.attrs) {
1184 ExportStatus::Export => {},
1185 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1186 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1188 let mut meth_gen_types = gen_types.push_ctx();
1189 assert!(meth_gen_types.learn_generics(&m.sig.generics, types));
1190 if m.defaultness.is_some() { unimplemented!(); }
1191 writeln_fn_docs(w, &m.attrs, "", types, Some(&meth_gen_types), m.sig.inputs.iter(), &m.sig.output);
1192 if let syn::ReturnType::Type(_, _) = &m.sig.output {
1193 writeln!(w, "#[must_use]").unwrap();
1195 write!(w, "#[no_mangle]\npub extern \"C\" fn {}_{}(", ident, m.sig.ident).unwrap();
1196 let ret_type = match &declared_type {
1197 DeclType::MirroredEnum => format!("{}", ident),
1198 DeclType::StructImported => format!("{}", ident),
1199 _ => unimplemented!(),
1201 write_method_params(w, &m.sig, &ret_type, types, Some(&meth_gen_types), false, true);
1202 write!(w, " {{\n\t").unwrap();
1203 write_method_var_decl_body(w, &m.sig, "", types, Some(&meth_gen_types), false);
1204 let mut takes_self = false;
1205 let mut takes_mut_self = false;
1206 let mut takes_owned_self = false;
1207 for inp in m.sig.inputs.iter() {
1208 if let syn::FnArg::Receiver(r) = inp {
1210 if r.mutability.is_some() { takes_mut_self = true; }
1211 if r.reference.is_none() { takes_owned_self = true; }
1214 if !takes_mut_self && !takes_self {
1215 write!(w, "{}::{}(", resolved_path, m.sig.ident).unwrap();
1217 match &declared_type {
1218 DeclType::MirroredEnum => write!(w, "this_arg.to_native().{}(", m.sig.ident).unwrap(),
1219 DeclType::StructImported => {
1220 if takes_owned_self {
1221 write!(w, "(*unsafe {{ Box::from_raw(this_arg.take_inner()) }}).{}(", m.sig.ident).unwrap();
1222 } else if takes_mut_self {
1223 write!(w, "unsafe {{ &mut (*ObjOps::untweak_ptr(this_arg.inner as *mut native{})) }}.{}(", ident, m.sig.ident).unwrap();
1225 write!(w, "unsafe {{ &*ObjOps::untweak_ptr(this_arg.inner) }}.{}(", m.sig.ident).unwrap();
1228 _ => unimplemented!(),
1231 write_method_call_params(w, &m.sig, "", types, Some(&meth_gen_types), &ret_type, false);
1232 writeln!(w, "\n}}\n").unwrap();
1239 } else if let Some(resolved_path) = types.maybe_resolve_ident(&ident) {
1240 if let Some(aliases) = types.crate_types.reverse_alias_map.get(&resolved_path).cloned() {
1241 'alias_impls: for (alias, arguments) in aliases {
1242 let alias_resolved = types.resolve_path(&alias, None);
1243 for (idx, gen) in i.generics.params.iter().enumerate() {
1245 syn::GenericParam::Type(type_param) => {
1246 'bounds_check: for bound in type_param.bounds.iter() {
1247 if let syn::TypeParamBound::Trait(trait_bound) = bound {
1248 if let syn::PathArguments::AngleBracketed(ref t) = &arguments {
1249 assert!(idx < t.args.len());
1250 if let syn::GenericArgument::Type(syn::Type::Path(p)) = &t.args[idx] {
1251 let generic_arg = types.resolve_path(&p.path, None);
1252 let generic_bound = types.resolve_path(&trait_bound.path, None);
1253 if let Some(traits_impld) = types.crate_types.trait_impls.get(&generic_arg) {
1254 for trait_impld in traits_impld {
1255 if *trait_impld == generic_bound { continue 'bounds_check; }
1257 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1258 continue 'alias_impls;
1260 eprintln!("struct {}'s generic arg {} didn't match bound {}", alias_resolved, generic_arg, generic_bound);
1261 continue 'alias_impls;
1263 } else { unimplemented!(); }
1264 } else { unimplemented!(); }
1265 } else { unimplemented!(); }
1268 syn::GenericParam::Lifetime(_) => {},
1269 syn::GenericParam::Const(_) => unimplemented!(),
1272 let aliased_impl = syn::ItemImpl {
1273 attrs: i.attrs.clone(),
1274 brace_token: syn::token::Brace(Span::call_site()),
1276 generics: syn::Generics {
1278 params: syn::punctuated::Punctuated::new(),
1282 impl_token: syn::Token![impl](Span::call_site()),
1283 items: i.items.clone(),
1284 self_ty: Box::new(syn::Type::Path(syn::TypePath { qself: None, path: alias.clone() })),
1285 trait_: i.trait_.clone(),
1288 writeln_impl(w, &aliased_impl, types);
1291 eprintln!("Not implementing anything for {} due to it being marked not exported", ident);
1294 eprintln!("Not implementing anything for {} due to no-resolve (probably the type isn't pub)", ident);
1300 /// Replaces upper case charachters with underscore followed by lower case except the first
1301 /// charachter and repeated upper case characthers (which are only made lower case).
1302 fn camel_to_snake_case(camel: &str) -> String {
1303 let mut res = "".to_string();
1304 let mut last_upper = -1;
1305 for (idx, c) in camel.chars().enumerate() {
1306 if c.is_uppercase() {
1307 if last_upper != idx as isize - 1 { res.push('_'); }
1308 res.push(c.to_lowercase().next().unwrap());
1309 last_upper = idx as isize;
1318 /// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum
1319 /// is unitary), we generate an equivalent enum with all types replaced with their C mapped
1320 /// versions followed by conversion functions which map between the Rust version and the C mapped
1322 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) {
1323 match export_status(&e.attrs) {
1324 ExportStatus::Export => {},
1325 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1326 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1329 if is_enum_opaque(e) {
1330 eprintln!("Skipping enum {} as it contains non-unit fields", e.ident);
1331 writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers);
1334 writeln_docs(w, &e.attrs, "");
1336 let mut gen_types = GenericTypes::new(None);
1337 assert!(gen_types.learn_generics(&e.generics, types));
1339 let mut needs_free = false;
1340 let mut constr = Vec::new();
1342 writeln!(w, "#[must_use]\n#[derive(Clone)]\n#[repr(C)]\npub enum {} {{", e.ident).unwrap();
1343 for var in e.variants.iter() {
1344 assert_eq!(export_status(&var.attrs), ExportStatus::Export); // We can't partially-export a mirrored enum
1345 writeln_docs(w, &var.attrs, "\t");
1346 write!(w, "\t{}", var.ident).unwrap();
1347 writeln!(&mut constr, "#[no_mangle]\n/// Utility method to constructs a new {}-variant {}", var.ident, e.ident).unwrap();
1348 let constr_name = camel_to_snake_case(&format!("{}", var.ident));
1349 write!(&mut constr, "pub extern \"C\" fn {}_{}(", e.ident, constr_name).unwrap();
1350 let mut empty_tuple_variant = false;
1351 if let syn::Fields::Named(fields) = &var.fields {
1353 writeln!(w, " {{").unwrap();
1354 for (idx, field) in fields.named.iter().enumerate() {
1355 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1356 writeln_field_docs(w, &field.attrs, "\t\t", types, Some(&gen_types), &field.ty);
1357 write!(w, "\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1358 write!(&mut constr, "{}{}: ", if idx != 0 { ", " } else { "" }, field.ident.as_ref().unwrap()).unwrap();
1359 types.write_c_type(w, &field.ty, Some(&gen_types), false);
1360 types.write_c_type(&mut constr, &field.ty, Some(&gen_types), false);
1361 writeln!(w, ",").unwrap();
1363 write!(w, "\t}}").unwrap();
1364 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1365 if fields.unnamed.len() == 1 {
1366 let mut empty_check = Vec::new();
1367 types.write_c_type(&mut empty_check, &fields.unnamed[0].ty, Some(&gen_types), false);
1368 if empty_check.is_empty() {
1369 empty_tuple_variant = true;
1372 if !empty_tuple_variant {
1374 write!(w, "(").unwrap();
1375 for (idx, field) in fields.unnamed.iter().enumerate() {
1376 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1377 write!(&mut constr, "{}: ", ('a' as u8 + idx as u8) as char).unwrap();
1378 types.write_c_type(w, &field.ty, Some(&gen_types), false);
1379 types.write_c_type(&mut constr, &field.ty, Some(&gen_types), false);
1380 if idx != fields.unnamed.len() - 1 {
1381 write!(w, ",").unwrap();
1382 write!(&mut constr, ",").unwrap();
1385 write!(w, ")").unwrap();
1388 if var.discriminant.is_some() { unimplemented!(); }
1389 write!(&mut constr, ") -> {} {{\n\t{}::{}", e.ident, e.ident, var.ident).unwrap();
1390 if let syn::Fields::Named(fields) = &var.fields {
1391 writeln!(&mut constr, " {{").unwrap();
1392 for field in fields.named.iter() {
1393 writeln!(&mut constr, "\t\t{},", field.ident.as_ref().unwrap()).unwrap();
1395 writeln!(&mut constr, "\t}}").unwrap();
1396 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1397 if !empty_tuple_variant {
1398 write!(&mut constr, "(").unwrap();
1399 for idx in 0..fields.unnamed.len() {
1400 write!(&mut constr, "{}, ", ('a' as u8 + idx as u8) as char).unwrap();
1402 writeln!(&mut constr, ")").unwrap();
1404 writeln!(&mut constr, "").unwrap();
1407 writeln!(&mut constr, "}}").unwrap();
1408 writeln!(w, ",").unwrap();
1410 writeln!(w, "}}\nuse {}::{} as native{};\nimpl {} {{", types.module_path, e.ident, e.ident, e.ident).unwrap();
1412 macro_rules! write_conv {
1413 ($fn_sig: expr, $to_c: expr, $ref: expr) => {
1414 writeln!(w, "\t#[allow(unused)]\n\tpub(crate) fn {} {{\n\t\tmatch {} {{", $fn_sig, if $to_c { "native" } else { "self" }).unwrap();
1415 for var in e.variants.iter() {
1416 write!(w, "\t\t\t{}{}::{} ", if $to_c { "native" } else { "" }, e.ident, var.ident).unwrap();
1417 let mut empty_tuple_variant = false;
1418 if let syn::Fields::Named(fields) = &var.fields {
1419 write!(w, "{{").unwrap();
1420 for field in fields.named.iter() {
1421 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1422 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, field.ident.as_ref().unwrap()).unwrap();
1424 write!(w, "}} ").unwrap();
1425 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1426 if fields.unnamed.len() == 1 {
1427 let mut empty_check = Vec::new();
1428 types.write_c_type(&mut empty_check, &fields.unnamed[0].ty, Some(&gen_types), false);
1429 if empty_check.is_empty() {
1430 empty_tuple_variant = true;
1433 if !empty_tuple_variant || $to_c {
1434 write!(w, "(").unwrap();
1435 for (idx, field) in fields.unnamed.iter().enumerate() {
1436 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1437 write!(w, "{}{}, ", if $ref { "ref " } else { "mut " }, ('a' as u8 + idx as u8) as char).unwrap();
1439 write!(w, ") ").unwrap();
1442 write!(w, "=>").unwrap();
1444 macro_rules! handle_field_a {
1445 ($field: expr, $field_ident: expr) => { {
1446 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1447 let mut sink = ::std::io::sink();
1448 let mut out: &mut dyn std::io::Write = if $ref { &mut sink } else { w };
1449 let new_var = if $to_c {
1450 types.write_to_c_conversion_new_var(&mut out, $field_ident, &$field.ty, Some(&gen_types), false)
1452 types.write_from_c_conversion_new_var(&mut out, $field_ident, &$field.ty, Some(&gen_types))
1454 if $ref || new_var {
1456 write!(w, "let mut {}_nonref = (*{}).clone();\n\t\t\t\t", $field_ident, $field_ident).unwrap();
1458 let nonref_ident = format_ident!("{}_nonref", $field_ident);
1460 types.write_to_c_conversion_new_var(w, &nonref_ident, &$field.ty, Some(&gen_types), false);
1462 types.write_from_c_conversion_new_var(w, &nonref_ident, &$field.ty, Some(&gen_types));
1464 write!(w, "\n\t\t\t\t").unwrap();
1467 write!(w, "\n\t\t\t\t").unwrap();
1472 if let syn::Fields::Named(fields) = &var.fields {
1473 write!(w, " {{\n\t\t\t\t").unwrap();
1474 for field in fields.named.iter() {
1475 handle_field_a!(field, field.ident.as_ref().unwrap());
1477 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1478 write!(w, " {{\n\t\t\t\t").unwrap();
1479 for (idx, field) in fields.unnamed.iter().enumerate() {
1480 if !empty_tuple_variant {
1481 handle_field_a!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1484 } else { write!(w, " ").unwrap(); }
1486 write!(w, "{}{}::{}", if $to_c { "" } else { "native" }, e.ident, var.ident).unwrap();
1488 macro_rules! handle_field_b {
1489 ($field: expr, $field_ident: expr) => { {
1490 if export_status(&$field.attrs) == ExportStatus::TestOnly { continue; }
1492 types.write_to_c_conversion_inline_prefix(w, &$field.ty, Some(&gen_types), false);
1494 types.write_from_c_conversion_prefix(w, &$field.ty, Some(&gen_types));
1496 write!(w, "{}{}", $field_ident,
1497 if $ref { "_nonref" } else { "" }).unwrap();
1499 types.write_to_c_conversion_inline_suffix(w, &$field.ty, Some(&gen_types), false);
1501 types.write_from_c_conversion_suffix(w, &$field.ty, Some(&gen_types));
1503 write!(w, ",").unwrap();
1507 if let syn::Fields::Named(fields) = &var.fields {
1508 write!(w, " {{").unwrap();
1509 for field in fields.named.iter() {
1510 if export_status(&field.attrs) == ExportStatus::TestOnly { continue; }
1511 write!(w, "\n\t\t\t\t\t{}: ", field.ident.as_ref().unwrap()).unwrap();
1512 handle_field_b!(field, field.ident.as_ref().unwrap());
1514 writeln!(w, "\n\t\t\t\t}}").unwrap();
1515 write!(w, "\t\t\t}}").unwrap();
1516 } else if let syn::Fields::Unnamed(fields) = &var.fields {
1517 if !empty_tuple_variant || !$to_c {
1518 write!(w, " (").unwrap();
1519 for (idx, field) in fields.unnamed.iter().enumerate() {
1520 write!(w, "\n\t\t\t\t\t").unwrap();
1521 handle_field_b!(field, &format_ident!("{}", ('a' as u8 + idx as u8) as char));
1523 writeln!(w, "\n\t\t\t\t)").unwrap();
1525 write!(w, "\t\t\t}}").unwrap();
1527 writeln!(w, ",").unwrap();
1529 writeln!(w, "\t\t}}\n\t}}").unwrap();
1533 write_conv!(format!("to_native(&self) -> native{}", e.ident), false, true);
1534 write_conv!(format!("into_native(self) -> native{}", e.ident), false, false);
1535 write_conv!(format!("from_native(native: &native{}) -> Self", e.ident), true, true);
1536 write_conv!(format!("native_into(native: native{}) -> Self", e.ident), true, false);
1537 writeln!(w, "}}").unwrap();
1540 writeln!(w, "/// Frees any resources used by the {}", e.ident).unwrap();
1541 writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap();
1543 writeln!(w, "/// Creates a copy of the {}", e.ident).unwrap();
1544 writeln!(w, "#[no_mangle]").unwrap();
1545 writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap();
1546 writeln!(w, "\torig.clone()").unwrap();
1547 writeln!(w, "}}").unwrap();
1548 w.write_all(&constr).unwrap();
1549 write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free, None);
1552 fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) {
1553 match export_status(&f.attrs) {
1554 ExportStatus::Export => {},
1555 ExportStatus::NoExport|ExportStatus::TestOnly => return,
1556 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1558 let mut gen_types = GenericTypes::new(None);
1559 if !gen_types.learn_generics(&f.sig.generics, types) { return; }
1561 writeln_fn_docs(w, &f.attrs, "", types, Some(&gen_types), f.sig.inputs.iter(), &f.sig.output);
1563 write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap();
1564 write_method_params(w, &f.sig, "", types, Some(&gen_types), false, true);
1565 write!(w, " {{\n\t").unwrap();
1566 write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false);
1567 write!(w, "{}::{}(", types.module_path, f.sig.ident).unwrap();
1568 write_method_call_params(w, &f.sig, "", types, Some(&gen_types), "", false);
1569 writeln!(w, "\n}}\n").unwrap();
1572 // ********************************
1573 // *** File/Crate Walking Logic ***
1574 // ********************************
1576 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) {
1577 // We want to ignore all items declared in this module (as they are not pub), but we still need
1578 // to give the ImportResolver any use statements, so we copy them here.
1579 let mut use_items = Vec::new();
1580 for item in module.content.as_ref().unwrap().1.iter() {
1581 if let syn::Item::Use(_) = item {
1582 use_items.push(item);
1585 let import_resolver = ImportResolver::from_borrowed_items(mod_path.splitn(2, "::").next().unwrap(), &libast.dependencies, mod_path, &use_items);
1586 let mut types = TypeResolver::new(mod_path, import_resolver, crate_types);
1588 writeln!(w, "mod {} {{\n{}", module.ident, DEFAULT_IMPORTS).unwrap();
1589 for item in module.content.as_ref().unwrap().1.iter() {
1591 syn::Item::Mod(m) => convert_priv_mod(w, libast, crate_types, out_dir, &format!("{}::{}", mod_path, module.ident), m),
1592 syn::Item::Impl(i) => {
1593 if let &syn::Type::Path(ref p) = &*i.self_ty {
1594 if p.path.get_ident().is_some() {
1595 writeln_impl(w, i, &mut types);
1602 writeln!(w, "}}").unwrap();
1605 /// Do the Real Work of mapping an original file to C-callable wrappers. Creates a new file at
1606 /// `out_path` and fills it with wrapper structs/functions to allow calling the things in the AST
1607 /// at `module` from C.
1608 fn convert_file<'a, 'b>(libast: &'a FullLibraryAST, crate_types: &CrateTypes<'a>, out_dir: &str, header_file: &mut File, cpp_header_file: &mut File) {
1609 for (module, astmod) in libast.modules.iter() {
1610 let orig_crate = module.splitn(2, "::").next().unwrap();
1611 let ASTModule { ref attrs, ref items, ref submods } = astmod;
1612 assert_eq!(export_status(&attrs), ExportStatus::Export);
1614 let new_file_path = if submods.is_empty() {
1615 format!("{}/{}.rs", out_dir, module.replace("::", "/"))
1616 } else if module != "" {
1617 format!("{}/{}/mod.rs", out_dir, module.replace("::", "/"))
1619 format!("{}/lib.rs", out_dir)
1621 let _ = std::fs::create_dir((&new_file_path.as_ref() as &std::path::Path).parent().unwrap());
1622 let mut out = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1623 .open(new_file_path).expect("Unable to open new src file");
1625 writeln!(out, "// This file is Copyright its original authors, visible in version control").unwrap();
1626 writeln!(out, "// history and in the source files from which this was generated.").unwrap();
1627 writeln!(out, "//").unwrap();
1628 writeln!(out, "// This file is licensed under the license available in the LICENSE or LICENSE.md").unwrap();
1629 writeln!(out, "// file in the root of this repository or, if no such file exists, the same").unwrap();
1630 writeln!(out, "// license as that which applies to the original source files from which this").unwrap();
1631 writeln!(out, "// source was automatically generated.").unwrap();
1632 writeln!(out, "").unwrap();
1634 writeln_docs(&mut out, &attrs, "");
1637 // Special-case the top-level lib.rs with various lint allows and a pointer to the c_types
1638 // and bitcoin hand-written modules.
1639 writeln!(out, "//! C Bindings").unwrap();
1640 writeln!(out, "#![allow(unknown_lints)]").unwrap();
1641 writeln!(out, "#![allow(non_camel_case_types)]").unwrap();
1642 writeln!(out, "#![allow(non_snake_case)]").unwrap();
1643 writeln!(out, "#![allow(unused_imports)]").unwrap();
1644 writeln!(out, "#![allow(unused_variables)]").unwrap();
1645 writeln!(out, "#![allow(unused_mut)]").unwrap();
1646 writeln!(out, "#![allow(unused_parens)]").unwrap();
1647 writeln!(out, "#![allow(unused_unsafe)]").unwrap();
1648 writeln!(out, "#![allow(unused_braces)]").unwrap();
1649 // TODO: We need to map deny(missing_docs) in the source crate(s)
1650 //writeln!(out, "#![deny(missing_docs)]").unwrap();
1651 writeln!(out, "pub mod version;").unwrap();
1652 writeln!(out, "pub mod c_types;").unwrap();
1653 writeln!(out, "pub mod bitcoin;").unwrap();
1655 writeln!(out, "{}", DEFAULT_IMPORTS).unwrap();
1659 writeln!(out, "pub mod {};", m).unwrap();
1662 eprintln!("Converting {} entries...", module);
1664 let import_resolver = ImportResolver::new(orig_crate, &libast.dependencies, module, items);
1665 let mut type_resolver = TypeResolver::new(module, import_resolver, crate_types);
1667 for item in items.iter() {
1669 syn::Item::Use(_) => {}, // Handled above
1670 syn::Item::Static(_) => {},
1671 syn::Item::Enum(e) => {
1672 if let syn::Visibility::Public(_) = e.vis {
1673 writeln_enum(&mut out, &e, &mut type_resolver, header_file, cpp_header_file);
1676 syn::Item::Impl(i) => {
1677 writeln_impl(&mut out, &i, &mut type_resolver);
1679 syn::Item::Struct(s) => {
1680 if let syn::Visibility::Public(_) = s.vis {
1681 writeln_struct(&mut out, &s, &mut type_resolver, header_file, cpp_header_file);
1684 syn::Item::Trait(t) => {
1685 if let syn::Visibility::Public(_) = t.vis {
1686 writeln_trait(&mut out, &t, &mut type_resolver, header_file, cpp_header_file);
1689 syn::Item::Mod(m) => {
1690 convert_priv_mod(&mut out, libast, crate_types, out_dir, &format!("{}::{}", module, m.ident), m);
1692 syn::Item::Const(c) => {
1693 // Re-export any primitive-type constants.
1694 if let syn::Visibility::Public(_) = c.vis {
1695 if let syn::Type::Path(p) = &*c.ty {
1696 let resolved_path = type_resolver.resolve_path(&p.path, None);
1697 if type_resolver.is_primitive(&resolved_path) {
1698 writeln_field_docs(&mut out, &c.attrs, "", &mut type_resolver, None, &*c.ty);
1699 writeln!(out, "\n#[no_mangle]").unwrap();
1700 writeln!(out, "pub static {}: {} = {}::{};", c.ident, resolved_path, module, c.ident).unwrap();
1705 syn::Item::Type(t) => {
1706 if let syn::Visibility::Public(_) = t.vis {
1707 match export_status(&t.attrs) {
1708 ExportStatus::Export => {},
1709 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1710 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1713 let mut process_alias = true;
1714 for tok in t.generics.params.iter() {
1715 if let syn::GenericParam::Lifetime(_) = tok {}
1716 else { process_alias = false; }
1720 syn::Type::Path(_) =>
1721 writeln_opaque(&mut out, &t.ident, &format!("{}", t.ident), &t.generics, &t.attrs, &type_resolver, header_file, cpp_header_file),
1727 syn::Item::Fn(f) => {
1728 if let syn::Visibility::Public(_) = f.vis {
1729 writeln_fn(&mut out, &f, &mut type_resolver);
1732 syn::Item::Macro(_) => {},
1733 syn::Item::Verbatim(_) => {},
1734 syn::Item::ExternCrate(_) => {},
1735 _ => unimplemented!(),
1739 out.flush().unwrap();
1743 fn walk_private_mod<'a>(ast_storage: &'a FullLibraryAST, orig_crate: &str, module: String, items: &'a syn::ItemMod, crate_types: &mut CrateTypes<'a>) {
1744 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, &module, &items.content.as_ref().unwrap().1);
1745 for item in items.content.as_ref().unwrap().1.iter() {
1747 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1748 syn::Item::Impl(i) => {
1749 if let &syn::Type::Path(ref p) = &*i.self_ty {
1750 if let Some(trait_path) = i.trait_.as_ref() {
1751 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1752 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1753 match crate_types.trait_impls.entry(sp) {
1754 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1755 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1767 /// Walk the FullLibraryAST, deciding how things will be mapped and adding tracking to CrateTypes.
1768 fn walk_ast<'a>(ast_storage: &'a FullLibraryAST, crate_types: &mut CrateTypes<'a>) {
1769 for (module, astmod) in ast_storage.modules.iter() {
1770 let ASTModule { ref attrs, ref items, submods: _ } = astmod;
1771 assert_eq!(export_status(&attrs), ExportStatus::Export);
1772 let orig_crate = module.splitn(2, "::").next().unwrap();
1773 let import_resolver = ImportResolver::new(orig_crate, &ast_storage.dependencies, module, items);
1775 for item in items.iter() {
1777 syn::Item::Struct(s) => {
1778 if let syn::Visibility::Public(_) = s.vis {
1779 match export_status(&s.attrs) {
1780 ExportStatus::Export => {},
1781 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1782 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1784 let struct_path = format!("{}::{}", module, s.ident);
1785 crate_types.opaques.insert(struct_path, &s.ident);
1788 syn::Item::Trait(t) => {
1789 if let syn::Visibility::Public(_) = t.vis {
1790 match export_status(&t.attrs) {
1791 ExportStatus::Export|ExportStatus::NotImplementable => {},
1792 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1794 let trait_path = format!("{}::{}", module, t.ident);
1795 walk_supertraits!(t, None, (
1797 crate_types.set_clonable("crate::".to_owned() + &trait_path);
1801 crate_types.traits.insert(trait_path, &t);
1804 syn::Item::Type(t) => {
1805 if let syn::Visibility::Public(_) = t.vis {
1806 match export_status(&t.attrs) {
1807 ExportStatus::Export => {},
1808 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1809 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1811 let type_path = format!("{}::{}", module, t.ident);
1812 let mut process_alias = true;
1813 for tok in t.generics.params.iter() {
1814 if let syn::GenericParam::Lifetime(_) = tok {}
1815 else { process_alias = false; }
1819 syn::Type::Path(p) => {
1820 let t_ident = &t.ident;
1822 // If its a path with no generics, assume we don't map the aliased type and map it opaque
1823 let path_obj = parse_quote!(#t_ident);
1824 let args_obj = p.path.segments.last().unwrap().arguments.clone();
1825 match crate_types.reverse_alias_map.entry(import_resolver.maybe_resolve_path(&p.path, None).unwrap()) {
1826 hash_map::Entry::Occupied(mut e) => { e.get_mut().push((path_obj, args_obj)); },
1827 hash_map::Entry::Vacant(e) => { e.insert(vec![(path_obj, args_obj)]); },
1830 crate_types.opaques.insert(type_path, t_ident);
1833 crate_types.type_aliases.insert(type_path, import_resolver.resolve_imported_refs((*t.ty).clone()));
1839 syn::Item::Enum(e) if is_enum_opaque(e) => {
1840 if let syn::Visibility::Public(_) = e.vis {
1841 match export_status(&e.attrs) {
1842 ExportStatus::Export => {},
1843 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1844 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1846 let enum_path = format!("{}::{}", module, e.ident);
1847 crate_types.opaques.insert(enum_path, &e.ident);
1850 syn::Item::Enum(e) => {
1851 if let syn::Visibility::Public(_) = e.vis {
1852 match export_status(&e.attrs) {
1853 ExportStatus::Export => {},
1854 ExportStatus::NoExport|ExportStatus::TestOnly => continue,
1855 ExportStatus::NotImplementable => panic!("(C-not implementable) must only appear on traits"),
1857 let enum_path = format!("{}::{}", module, e.ident);
1858 crate_types.mirrored_enums.insert(enum_path, &e);
1861 syn::Item::Impl(i) => {
1862 if let &syn::Type::Path(ref p) = &*i.self_ty {
1863 if let Some(trait_path) = i.trait_.as_ref() {
1864 if path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) ||
1865 path_matches_nongeneric(&trait_path.1, &["Clone"]) {
1866 if let Some(full_path) = import_resolver.maybe_resolve_path(&p.path, None) {
1867 crate_types.set_clonable("crate::".to_owned() + &full_path);
1870 if let Some(tp) = import_resolver.maybe_resolve_path(&trait_path.1, None) {
1871 if let Some(sp) = import_resolver.maybe_resolve_path(&p.path, None) {
1872 match crate_types.trait_impls.entry(sp) {
1873 hash_map::Entry::Occupied(mut e) => { e.get_mut().push(tp); },
1874 hash_map::Entry::Vacant(e) => { e.insert(vec![tp]); },
1881 syn::Item::Mod(m) => walk_private_mod(ast_storage, orig_crate, format!("{}::{}", module, m.ident), m, crate_types),
1889 let args: Vec<String> = env::args().collect();
1890 if args.len() != 5 {
1891 eprintln!("Usage: target/dir derived_templates.rs extra/includes.h extra/cpp/includes.hpp");
1895 let mut derived_templates = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1896 .open(&args[2]).expect("Unable to open new header file");
1897 let mut header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1898 .open(&args[3]).expect("Unable to open new header file");
1899 let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
1900 .open(&args[4]).expect("Unable to open new header file");
1902 writeln!(header_file, "#if defined(__GNUC__)").unwrap();
1903 writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
1904 writeln!(header_file, "#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
1905 writeln!(header_file, "#else").unwrap();
1906 writeln!(header_file, "#define MUST_USE_STRUCT").unwrap();
1907 writeln!(header_file, "#define MUST_USE_RES").unwrap();
1908 writeln!(header_file, "#endif").unwrap();
1909 writeln!(header_file, "#if defined(__clang__)").unwrap();
1910 writeln!(header_file, "#define NONNULL_PTR _Nonnull").unwrap();
1911 writeln!(header_file, "#else").unwrap();
1912 writeln!(header_file, "#define NONNULL_PTR").unwrap();
1913 writeln!(header_file, "#endif").unwrap();
1914 writeln!(cpp_header_file, "#include <string.h>\nnamespace LDK {{").unwrap();
1916 // Write a few manually-defined types into the C++ header file
1917 write_cpp_wrapper(&mut cpp_header_file, "Str", true, None);
1919 // First parse the full crate's ASTs, caching them so that we can hold references to the AST
1920 // objects in other datastructures:
1921 let mut lib_src = String::new();
1922 std::io::stdin().lock().read_to_string(&mut lib_src).unwrap();
1923 let lib_syntax = syn::parse_file(&lib_src).expect("Unable to parse file");
1924 let libast = FullLibraryAST::load_lib(lib_syntax);
1926 // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
1927 // when parsing other file ASTs...
1928 let mut libtypes = CrateTypes::new(&mut derived_templates, &libast);
1929 walk_ast(&libast, &mut libtypes);
1931 // ... finally, do the actual file conversion/mapping, writing out types as we go.
1932 convert_file(&libast, &libtypes, &args[1], &mut header_file, &mut cpp_header_file);
1934 // For container templates which we created while walking the crate, make sure we add C++
1935 // mapped types so that C++ users can utilize the auto-destructors available.
1936 for (ty, has_destructor) in libtypes.templates_defined.borrow().iter() {
1937 write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor, None);
1939 writeln!(cpp_header_file, "}}").unwrap();
1941 header_file.flush().unwrap();
1942 cpp_header_file.flush().unwrap();
1943 derived_templates.flush().unwrap();