X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=c-bindings-gen%2Fsrc%2Fmain.rs;h=c8adf7df1b6e7238c0a907c8aa4662019dc3b70b;hb=75e8cf5acf256d8ecaf0c68e60997f6423e83c04;hp=8bbbdf03765579e5636c49aa3dfd9e937cee8768;hpb=d26e7c63d7321a7da2afd2efc52296e19ddd641b;p=ldk-c-bindings diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs index 8bbbdf0..c8adf7d 100644 --- a/c-bindings-gen/src/main.rs +++ b/c-bindings-gen/src/main.rs @@ -237,7 +237,9 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty writeln!(w, "\t/// An opaque pointer which is passed to your function implementations as an argument.").unwrap(); writeln!(w, "\t/// This has no meaning in the LDK, and can be NULL or any other value.").unwrap(); writeln!(w, "\tpub this_arg: *mut c_void,").unwrap(); - let mut generated_fields = Vec::new(); // Every field's (name, is_clonable) except this_arg, used in Clone generation + // We store every field's (name, Option, docs) except this_arg, used in Clone generation + // docs is only set if its a function which should be callable on the object itself in C++ + let mut generated_fields = Vec::new(); for item in t.items.iter() { match item { &syn::TraitItem::Method(ref m) => { @@ -271,19 +273,18 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty // happen) as well as provide an Option<>al function pointer which is // called when the trait method is called which allows updating on the fly. write!(w, "\tpub {}: ", m.sig.ident).unwrap(); - generated_fields.push((format!("{}", m.sig.ident), true)); + generated_fields.push((format!("{}", m.sig.ident), None, None)); types.write_c_type(w, &*r.elem, Some(&meth_gen_types), false); writeln!(w, ",").unwrap(); writeln!(w, "\t/// Fill in the {} field as a reference to it will be given to Rust after this returns", m.sig.ident).unwrap(); writeln!(w, "\t/// Note that this takes a pointer to this object, not the this_ptr like other methods do").unwrap(); writeln!(w, "\t/// This function pointer may be NULL if {} is filled in when this object is created and never needs updating.", m.sig.ident).unwrap(); writeln!(w, "\tpub set_{}: Option,", m.sig.ident, trait_name).unwrap(); - generated_fields.push((format!("set_{}", m.sig.ident), true)); + generated_fields.push((format!("set_{}", m.sig.ident), None, None)); // Note that cbindgen will now generate - // typedef struct Thing {..., set_thing: (const Thing*), ...} Thing; + // typedef struct Thing {..., set_thing: (const struct Thing*), ...} Thing; // which does not compile since Thing is not defined before it is used. writeln!(extra_headers, "struct LDK{};", trait_name).unwrap(); - writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap(); continue; } // Sadly, this currently doesn't do what we want, but it should be easy to get @@ -291,8 +292,12 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty writeln!(w, "\t#[must_use]").unwrap(); } + let mut cpp_docs = Vec::new(); + writeln_docs(&mut cpp_docs, &m.attrs, "\t * "); + let docs_string = "\t/**\n".to_owned() + &String::from_utf8(cpp_docs).unwrap().replace("///", "") + "\t */\n"; + write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap(); - generated_fields.push((format!("{}", m.sig.ident), true)); + generated_fields.push((format!("{}", m.sig.ident), None, Some(docs_string))); write_method_params(w, &m.sig, "c_void", types, Some(&meth_gen_types), true, false); writeln!(w, ",").unwrap(); }, @@ -301,56 +306,53 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty } } // Add functions which may be required for supertrait implementations. - let mut requires_clone = false; - walk_supertraits!(t, Some(&types), ( - ("Clone", _) => requires_clone = true, - (_, _) => {} - ) ); walk_supertraits!(t, Some(&types), ( ("Clone", _) => { - writeln!(w, "\t/// Creates a copy of the object pointed to by this_arg, for a copy of this {}.", trait_name).unwrap(); - writeln!(w, "\t/// Note that the ultimate copy of the {} will have all function pointers the same as the original.", trait_name).unwrap(); - writeln!(w, "\t/// May be NULL if no action needs to be taken, the this_arg pointer will be copied into the new {}.", trait_name).unwrap(); - writeln!(w, "\tpub clone: Option *mut c_void>,").unwrap(); - generated_fields.push(("clone".to_owned(), true)); + writeln!(w, "\t/// Called, if set, after this {} has been cloned into a duplicate object.", trait_name).unwrap(); + writeln!(w, "\t/// The new {} is provided, and should be mutated as needed to perform a", trait_name).unwrap(); + writeln!(w, "\t/// deep copy of the object pointed to by this_arg or avoid any double-freeing.").unwrap(); + writeln!(w, "\tpub cloned: Option,", trait_name, trait_name).unwrap(); + generated_fields.push(("cloned".to_owned(), None, None)); }, ("std::cmp::Eq", _)|("core::cmp::Eq", _) => { - writeln!(w, "\t/// Checks if two objects are equal given this object's this_arg pointer and another object.").unwrap(); + let eq_docs = "Checks if two objects are equal given this object's this_arg pointer and another object."; + writeln!(w, "\t/// {}", eq_docs).unwrap(); writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap(); - writeln!(extra_headers, "typedef struct LDK{} LDK{};", trait_name, trait_name).unwrap(); - generated_fields.push(("eq".to_owned(), true)); + generated_fields.push(("eq".to_owned(), None, Some(format!("\t/** {} */\n", eq_docs)))); }, ("std::hash::Hash", _)|("core::hash::Hash", _) => { - writeln!(w, "\t/// Calculate a succinct non-cryptographic hash for an object given its this_arg pointer.").unwrap(); - writeln!(w, "\t/// This is used, for example, for inclusion of this object in a hash map.").unwrap(); + let hash_docs_a = "Calculate a succinct non-cryptographic hash for an object given its this_arg pointer."; + let hash_docs_b = "This is used, for example, for inclusion of this object in a hash map."; + writeln!(w, "\t/// {}", hash_docs_a).unwrap(); + writeln!(w, "\t/// {}", hash_docs_b).unwrap(); writeln!(w, "\tpub hash: extern \"C\" fn (this_arg: *const c_void) -> u64,").unwrap(); - generated_fields.push(("hash".to_owned(), true)); + generated_fields.push(("hash".to_owned(), None, + Some(format!("\t/**\n\t * {}\n\t * {}\n\t */\n", hash_docs_a, hash_docs_b)))); }, ("Send", _) => {}, ("Sync", _) => {}, (s, i) => { + // TODO: Both of the below should expose supertrait methods in C++, but doing so is + // nontrivial. generated_fields.push(if types.crate_types.traits.get(s).is_none() { let (docs, name, ret) = convert_trait_impl_field(s); writeln!(w, "\t/// {}", docs).unwrap(); writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap(); - (name, true) // Assume clonable + (name, None, None) // Assume clonable } else { // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member. writeln!(w, "\t/// Implementation of {} for this object.", i).unwrap(); - writeln!(w, "\tpub {}: crate::{},", i, s).unwrap(); let is_clonable = types.is_clonable(s); - if !is_clonable && requires_clone { - writeln!(w, "\t/// Creates a copy of the {}, for a copy of this {}.", i, trait_name).unwrap(); - writeln!(w, "\t/// Because {} doesn't natively support copying itself, you have to provide a full copy implementation here.", i).unwrap(); - writeln!(w, "\tpub {}_clone: extern \"C\" fn (orig_{}: &{}) -> {},", i, i, i, i).unwrap(); - } - (format!("{}", i), is_clonable) + writeln!(w, "\tpub {}: crate::{},", i, s).unwrap(); + (format!("{}", i), if !is_clonable { + Some(format!("crate::{}_clone_fields", s)) + } else { None }, None) }); } ) ); writeln!(w, "\t/// Frees any resources associated with this object given its this_arg pointer.").unwrap(); 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(); writeln!(w, "\tpub free: Option,").unwrap(); - generated_fields.push(("free".to_owned(), true)); + generated_fields.push(("free".to_owned(), None, None)); writeln!(w, "}}").unwrap(); macro_rules! impl_trait_for_c { @@ -429,7 +431,9 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty } write_method_var_decl_body(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), true); write!(w, "(self{}.{})(", $impl_accessor, m.sig.ident).unwrap(); - write_method_call_params(w, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), "", true); + let mut args = Vec::new(); + write_method_call_params(&mut args, &m.sig, "\t", $type_resolver, Some(&meth_gen_types), "", true); + w.write_all(String::from_utf8(args).unwrap().replace("self", &format!("self{}", $impl_accessor)).as_bytes()).unwrap(); writeln!(w, "\n\t}}").unwrap(); }, @@ -453,6 +457,20 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(); writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(); + writeln!(w, "#[no_mangle]").unwrap(); + writeln!(w, "pub(crate) extern \"C\" fn {}_clone_fields(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap(); + writeln!(w, "\t{} {{", trait_name).unwrap(); + writeln!(w, "\t\tthis_arg: orig.this_arg,").unwrap(); + for (field, clone_fn, _) in generated_fields.iter() { + if let Some(f) = clone_fn { + // If the field isn't clonable, blindly assume its a trait and hope for the best. + writeln!(w, "\t\t{}: {}(&orig.{}),", field, f, field).unwrap(); + } else { + writeln!(w, "\t\t{}: Clone::clone(&orig.{}),", field, field).unwrap(); + } + } + writeln!(w, "\t}}\n}}").unwrap(); + // Implement supertraits for the C-mapped struct. walk_supertraits!(t, Some(&types), ( ("std::cmp::Eq", _)|("core::cmp::Eq", _) => { @@ -469,17 +487,9 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty writeln!(w, "#[no_mangle]").unwrap(); writeln!(w, "/// Creates a copy of a {}", trait_name).unwrap(); writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", trait_name, trait_name, trait_name).unwrap(); - writeln!(w, "\t{} {{", trait_name).unwrap(); - writeln!(w, "\t\tthis_arg: if let Some(f) = orig.clone {{ (f)(orig.this_arg) }} else {{ orig.this_arg }},").unwrap(); - for (field, clonable) in generated_fields.iter() { - if *clonable { - writeln!(w, "\t\t{}: Clone::clone(&orig.{}),", field, field).unwrap(); - } else { - writeln!(w, "\t\t{}: (orig.{}_clone)(&orig.{}),", field, field, field).unwrap(); - writeln!(w, "\t\t{}_clone: orig.{}_clone,", field, field).unwrap(); - } - } - writeln!(w, "\t}}\n}}").unwrap(); + writeln!(w, "\tlet mut res = {}_clone_fields(orig);", trait_name).unwrap(); + writeln!(w, "\tif let Some(f) = orig.cloned {{ (f)(&mut res) }};").unwrap(); + writeln!(w, "\tres\n}}").unwrap(); writeln!(w, "impl Clone for {} {{", trait_name).unwrap(); writeln!(w, "\tfn clone(&self) -> Self {{").unwrap(); writeln!(w, "\t\t{}_clone(self)", trait_name).unwrap(); @@ -524,7 +534,8 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty writeln!(w, "\t\t\tf(self.this_arg);").unwrap(); writeln!(w, "\t\t}}\n\t}}\n}}").unwrap(); - write_cpp_wrapper(cpp_headers, &trait_name, true); + write_cpp_wrapper(cpp_headers, &trait_name, true, Some(generated_fields.drain(..) + .filter_map(|(name, _, docs)| if let Some(docs) = docs { Some((name, docs)) } else { None }).collect())); } /// Write out a simple "opaque" type (eg structs) which contain a pointer to the native Rust type @@ -569,7 +580,7 @@ fn writeln_opaque(w: &mut W, ident: &syn::Ident, struct_name: writeln!(w, "\t\tret").unwrap(); writeln!(w, "\t}}\n}}").unwrap(); - write_cpp_wrapper(cpp_headers, &format!("{}", ident), true); + write_cpp_wrapper(cpp_headers, &format!("{}", ident), true, None); } /// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate @@ -805,13 +816,10 @@ fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut Typ } } let mut requires_clone = false; - walk_supertraits!(trait_obj, Some(&types), ( - ("Clone", _) => requires_clone = true, - (_, _) => {} - ) ); walk_supertraits!(trait_obj, Some(&types), ( ("Clone", _) => { - writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap(); + requires_clone = true; + writeln!(w, "\t\tcloned: Some({}_{}_cloned),", trait_obj.ident, ident).unwrap(); }, ("Sync", _) => {}, ("Send", _) => {}, ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {}, @@ -829,9 +837,6 @@ fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut Typ } } write!(w, "\t\t}},\n").unwrap(); - if !types.is_clonable(s) && requires_clone { - writeln!(w, "\t\t{}_clone: {}_{}_clone,", t, ident, t).unwrap(); - } } else { write_trait_impl_field_assign(w, s, ident); } @@ -916,27 +921,21 @@ fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut Typ _ => unimplemented!(), } } - walk_supertraits!(trait_obj, Some(&types), ( - (s, t) => { - if let Some(supertrait_obj) = types.crate_types.traits.get(s) { - if !types.is_clonable(s) && requires_clone { - writeln!(w, "extern \"C\" fn {}_{}_clone(orig: &crate::{}) -> crate::{} {{", ident, t, s, s).unwrap(); - writeln!(w, "\tcrate::{} {{", s).unwrap(); - writeln!(w, "\t\tthis_arg: orig.this_arg,").unwrap(); - writeln!(w, "\t\tfree: None,").unwrap(); - for item in supertrait_obj.items.iter() { - match item { - syn::TraitItem::Method(m) => { - write_meth!(m, supertrait_obj, ""); - }, - _ => {}, - } - } - write!(w, "\t}}\n}}\n").unwrap(); + if requires_clone { + writeln!(w, "extern \"C\" fn {}_{}_cloned(new_obj: &mut crate::{}) {{", trait_obj.ident, ident, full_trait_path).unwrap(); + writeln!(w, "\tnew_obj.this_arg = {}_clone_void(new_obj.this_arg);", ident).unwrap(); + writeln!(w, "\tnew_obj.free = Some({}_free_void);", ident).unwrap(); + walk_supertraits!(trait_obj, Some(&types), ( + (s, t) => { + if types.crate_types.traits.get(s).is_some() { + assert!(!types.is_clonable(s)); // We don't currently support cloning with a clonable supertrait + writeln!(w, "\tnew_obj.{}.this_arg = new_obj.this_arg;", t).unwrap(); + writeln!(w, "\tnew_obj.{}.free = None;", t).unwrap(); } } - } - ) ); + ) ); + writeln!(w, "}}").unwrap(); + } write!(w, "\n").unwrap(); } else if path_matches_nongeneric(&trait_path.1, &["From"]) { } else if path_matches_nongeneric(&trait_path.1, &["Default"]) { @@ -1374,7 +1373,7 @@ fn writeln_enum<'a, 'b, W: std::io::Write>(w: &mut W, e: &'a syn::ItemEnum, type writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", e.ident, e.ident, e.ident).unwrap(); writeln!(w, "\torig.clone()").unwrap(); writeln!(w, "}}").unwrap(); - write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free); + write_cpp_wrapper(cpp_headers, &format!("{}", e.ident), needs_free, None); } fn writeln_fn<'a, 'b, W: std::io::Write>(w: &mut W, f: &'a syn::ItemFn, types: &mut TypeResolver<'b, 'a>) { @@ -1758,7 +1757,7 @@ fn main() { // For container templates which we created while walking the crate, make sure we add C++ // mapped types so that C++ users can utilize the auto-destructors available. for (ty, has_destructor) in libtypes.templates_defined.borrow().iter() { - write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor); + write_cpp_wrapper(&mut cpp_header_file, ty, *has_destructor, None); } writeln!(cpp_header_file, "}}").unwrap();