[bindings] Move to manual write-out for Vec, too
[rust-lightning] / c-bindings-gen / src / main.rs
index ffb70f92001e0b346b65bb97d2703e7d4b1854dd..d927d2ae71c816af9f92ee824861103715117d0f 100644 (file)
@@ -10,7 +10,7 @@
 //! It also generates relevant memory-management functions and free-standing functions with
 //! parameters mapped.
 
-use std::collections::HashMap;
+use std::collections::{HashMap, HashSet};
 use std::env;
 use std::fs::File;
 use std::io::{Read, Write};
@@ -38,7 +38,7 @@ fn convert_macro<W: std::io::Write>(w: &mut W, macro_path: &syn::Path, stream: &
                        if let Some(s) = types.maybe_resolve_ident(&struct_for) {
                                if !types.crate_types.opaques.get(&s).is_some() { return; }
                                writeln!(w, "#[no_mangle]").unwrap();
-                               writeln!(w, "pub extern \"C\" fn {}_write(obj: *const {}) -> crate::c_types::derived::CVec_u8Z {{", struct_for, struct_for).unwrap();
+                               writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", struct_for, struct_for).unwrap();
                                writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap();
                                writeln!(w, "}}").unwrap();
                                writeln!(w, "#[no_mangle]").unwrap();
@@ -65,7 +65,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                let full_obj_path;
                let mut has_inner = false;
                if let syn::Type::Path(ref p) = for_ty {
-                       if let Some(ident) = p.path.get_ident() {
+                       if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
                                for_obj = format!("{}", ident);
                                full_obj_path = for_obj.clone();
                                has_inner = types.c_type_has_inner_from_path(&types.resolve_path(&p.path, Some(generics)));
@@ -83,7 +83,7 @@ fn maybe_convert_trait_impl<W: std::io::Write>(w: &mut W, trait_path: &syn::Path
                match &t as &str {
                        "util::ser::Writeable" => {
                                writeln!(w, "#[no_mangle]").unwrap();
-                               writeln!(w, "pub extern \"C\" fn {}_write(obj: *const {}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, full_obj_path).unwrap();
+                               writeln!(w, "pub extern \"C\" fn {}_write(obj: &{}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, full_obj_path).unwrap();
 
                                let ref_type = syn::Type::Reference(syn::TypeReference {
                                        and_token: syn::Token!(&)(Span::call_site()), lifetime: None, mutability: None,
@@ -233,15 +233,20 @@ macro_rules! walk_supertraits { ($t: expr, $types: expr, ($( $pat: pat => $e: ex
                                        }
                                        // First try to resolve path to find in-crate traits, but if that doesn't work
                                        // assume its a prelude trait (eg Clone, etc) and just use the single ident.
-                                       if let Some(path) = $types.maybe_resolve_path(&supertrait.path, None) {
-                                               match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
-                                                       $( $pat => $e, )*
+                                       let types_opt: Option<&TypeResolver> = $types;
+                                       if let Some(types) = types_opt {
+                                               if let Some(path) = types.maybe_resolve_path(&supertrait.path, None) {
+                                                       match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
+                                                               $( $pat => $e, )*
+                                                       }
+                                                       continue;
                                                }
-                                       } else if let Some(ident) = supertrait.path.get_ident() {
+                                       }
+                                       if let Some(ident) = supertrait.path.get_ident() {
                                                match (&format!("{}", ident) as &str, &ident) {
                                                        $( $pat => $e, )*
                                                }
-                                       } else {
+                                       } else if types_opt.is_some() {
                                                panic!("Supertrait unresolvable and not single-ident");
                                        }
                                },
@@ -337,7 +342,7 @@ 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.
-       walk_supertraits!(t, types, (
+       walk_supertraits!(t, Some(&types), (
                ("Clone", _) => {
                        writeln!(w, "\tpub clone: Option<extern \"C\" fn (this_arg: *const c_void) -> *mut c_void>,").unwrap();
                        generated_fields.push("clone".to_owned());
@@ -368,7 +373,7 @@ fn writeln_trait<'a, 'b, W: std::io::Write>(w: &mut W, t: &'a syn::ItemTrait, ty
        generated_fields.push("free".to_owned());
        writeln!(w, "}}").unwrap();
        // Implement supertraits for the C-mapped struct.
-       walk_supertraits!(t, types, (
+       walk_supertraits!(t, Some(&types), (
                ("Send", _) => writeln!(w, "unsafe impl Send for {} {{}}", trait_name).unwrap(),
                ("Sync", _) => writeln!(w, "unsafe impl Sync for {} {{}}", trait_name).unwrap(),
                ("std::cmp::Eq", _) => {
@@ -550,40 +555,22 @@ fn writeln_opaque<W: std::io::Write>(w: &mut W, ident: &syn::Ident, struct_name:
        writeln!(w, "\t\tret").unwrap();
        writeln!(w, "\t}}\n}}").unwrap();
 
-       'attr_loop: for attr in attrs.iter() {
-               let tokens_clone = attr.tokens.clone();
-               let mut token_iter = tokens_clone.into_iter();
-               if let Some(token) = token_iter.next() {
-                       match token {
-                               TokenTree::Group(g) => {
-                                       if format!("{}", single_ident_generic_path_to_ident(&attr.path).unwrap()) == "derive" {
-                                               for id in g.stream().into_iter() {
-                                                       if let TokenTree::Ident(i) = id {
-                                                               if i == "Clone" {
-                                                                       writeln!(w, "impl Clone for {} {{", struct_name).unwrap();
-                                                                       writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
-                                                                       writeln!(w, "\t\tSelf {{").unwrap();
-                                                                       writeln!(w, "\t\t\tinner: Box::into_raw(Box::new(unsafe {{ &*self.inner }}.clone())),").unwrap();
-                                                                       writeln!(w, "\t\t\tis_owned: true,").unwrap();
-                                                                       writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
-                                                                       writeln!(w, "#[allow(unused)]").unwrap();
-                                                                       writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
-                                                                       writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", struct_name).unwrap();
-                                                                       writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", struct_name).unwrap();
-                                                                       writeln!(w, "}}").unwrap();
-                                                                       writeln!(w, "#[no_mangle]").unwrap();
-                                                                       writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", struct_name, struct_name, struct_name).unwrap();
-                                                                       writeln!(w, "\t{} {{ inner: Box::into_raw(Box::new(unsafe {{ &*orig.inner }}.clone())), is_owned: true }}", struct_name).unwrap();
-                                                                       writeln!(w, "}}").unwrap();
-                                                                       break 'attr_loop;
-                                                               }
-                                                       }
-                                               }
-                                       }
-                               },
-                               _ => {},
-                       }
-               }
+       if attrs_derives_clone(attrs) {
+               writeln!(w, "impl Clone for {} {{", struct_name).unwrap();
+               writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
+               writeln!(w, "\t\tSelf {{").unwrap();
+               writeln!(w, "\t\t\tinner: Box::into_raw(Box::new(unsafe {{ &*self.inner }}.clone())),").unwrap();
+               writeln!(w, "\t\t\tis_owned: true,").unwrap();
+               writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
+               writeln!(w, "#[allow(unused)]").unwrap();
+               writeln!(w, "/// Used only if an object of this type is returned as a trait impl by a method").unwrap();
+               writeln!(w, "pub(crate) extern \"C\" fn {}_clone_void(this_ptr: *const c_void) -> *mut c_void {{", struct_name).unwrap();
+               writeln!(w, "\tBox::into_raw(Box::new(unsafe {{ (*(this_ptr as *mut native{})).clone() }})) as *mut c_void", struct_name).unwrap();
+               writeln!(w, "}}").unwrap();
+               writeln!(w, "#[no_mangle]").unwrap();
+               writeln!(w, "pub extern \"C\" fn {}_clone(orig: &{}) -> {} {{", struct_name, struct_name, struct_name).unwrap();
+               writeln!(w, "\t{} {{ inner: Box::into_raw(Box::new(unsafe {{ &*orig.inner }}.clone())), is_owned: true }}", struct_name).unwrap();
+               writeln!(w, "}}").unwrap();
        }
 
        write_cpp_wrapper(cpp_headers, &format!("{}", ident), true);
@@ -706,6 +693,11 @@ fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct,
 ///
 /// A few non-crate Traits are hard-coded including Default.
 fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut TypeResolver) {
+       match export_status(&i.attrs) {
+               ExportStatus::Export => {},
+               ExportStatus::NoExport|ExportStatus::TestOnly => return,
+       }
+
        if let syn::Type::Tuple(_) = &*i.self_ty {
                if types.understood_c_type(&*i.self_ty, None) {
                        let mut gen_types = GenericTypes::new();
@@ -786,7 +778,7 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                writeln!(w, "\t\tret.free = Some({}_free_void);", ident).unwrap();
                                                writeln!(w, "\t\tret\n\t}}\n}}").unwrap();
 
-                                               write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: *const {}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
+                                               write!(w, "#[no_mangle]\npub extern \"C\" fn {}_as_{}(this_arg: &{}) -> crate::{} {{\n", ident, trait_obj.ident, ident, full_trait_path).unwrap();
                                                writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
                                                writeln!(w, "\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
                                                writeln!(w, "\t\tfree: None,").unwrap();
@@ -827,7 +819,7 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                                _ => {},
                                                        }
                                                }
-                                               walk_supertraits!(trait_obj, types, (
+                                               walk_supertraits!(trait_obj, Some(&types), (
                                                        ("Clone", _) => {
                                                                writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap();
                                                        },
@@ -925,7 +917,7 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                                _ => unimplemented!(),
                                                        }
                                                }
-                                               walk_supertraits!(trait_obj, types, (
+                                               walk_supertraits!(trait_obj, Some(&types), (
                                                        (s, t) => {
                                                                if let Some(supertrait_obj) = types.crate_types.traits.get(s).cloned() {
                                                                        writeln!(w, "use {}::{} as native{}Trait;", types.orig_crate, s, t).unwrap();
@@ -952,10 +944,9 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                        },
                                                        "PartialEq" => {},
                                                        // If we have no generics, try a manual implementation:
-                                                       _ if p.path.get_ident().is_some() => maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types),
-                                                       _ => {},
+                                                       _ => maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types),
                                                }
-                                       } else if p.path.get_ident().is_some() {
+                                       } else {
                                                // If we have no generics, try a manual implementation:
                                                maybe_convert_trait_impl(w, &trait_path.1, &*i.self_ty, types, &gen_types);
                                        }
@@ -1475,6 +1466,10 @@ fn walk_ast<'a>(in_dir: &str, path: &str, module: String, ast_storage: &'a FullL
                                                ExportStatus::NoExport|ExportStatus::TestOnly => continue,
                                        }
                                        let struct_path = format!("{}::{}", module, s.ident);
+                                       if attrs_derives_clone(&s.attrs) {
+                                               crate_types.clonable_types.insert("crate::".to_owned() + &struct_path);
+                                       }
+
                                        crate_types.opaques.insert(struct_path, &s.ident);
                                }
                        },
@@ -1485,6 +1480,12 @@ fn walk_ast<'a>(in_dir: &str, path: &str, module: String, ast_storage: &'a FullL
                                                ExportStatus::NoExport|ExportStatus::TestOnly => continue,
                                        }
                                        let trait_path = format!("{}::{}", module, t.ident);
+                                       walk_supertraits!(t, None, (
+                                               ("Clone", _) => {
+                                                       crate_types.clonable_types.insert("crate::".to_owned() + &trait_path);
+                                               },
+                                               (_, _) => {}
+                                       ) );
                                        crate_types.traits.insert(trait_path, &t);
                                }
                        },
@@ -1520,6 +1521,9 @@ fn walk_ast<'a>(in_dir: &str, path: &str, module: String, ast_storage: &'a FullL
                                                ExportStatus::NoExport|ExportStatus::TestOnly => continue,
                                        }
                                        let enum_path = format!("{}::{}", module, e.ident);
+                                       if attrs_derives_clone(&e.attrs) {
+                                               crate_types.clonable_types.insert("crate::".to_owned() + &enum_path);
+                                       }
                                        crate_types.opaques.insert(enum_path, &e.ident);
                                }
                        },
@@ -1530,6 +1534,9 @@ fn walk_ast<'a>(in_dir: &str, path: &str, module: String, ast_storage: &'a FullL
                                                ExportStatus::NoExport|ExportStatus::TestOnly => continue,
                                        }
                                        let enum_path = format!("{}::{}", module, e.ident);
+                                       if attrs_derives_clone(&e.attrs) {
+                                               crate_types.clonable_types.insert("crate::".to_owned() + &enum_path);
+                                       }
                                        crate_types.mirrored_enums.insert(enum_path, &e);
                                }
                        },
@@ -1552,10 +1559,18 @@ fn main() {
        let mut cpp_header_file = std::fs::OpenOptions::new().write(true).create(true).truncate(true)
                .open(&args[6]).expect("Unable to open new header file");
 
-       writeln!(header_file, "#if defined(__GNUC__)\n#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
-       writeln!(header_file, "#else\n#define MUST_USE_STRUCT\n#endif").unwrap();
-       writeln!(header_file, "#if defined(__GNUC__)\n#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
-       writeln!(header_file, "#else\n#define MUST_USE_RES\n#endif").unwrap();
+       writeln!(header_file, "#if defined(__GNUC__)").unwrap();
+       writeln!(header_file, "#define MUST_USE_STRUCT __attribute__((warn_unused))").unwrap();
+       writeln!(header_file, "#define MUST_USE_RES __attribute__((warn_unused_result))").unwrap();
+       writeln!(header_file, "#else").unwrap();
+       writeln!(header_file, "#define MUST_USE_STRUCT").unwrap();
+       writeln!(header_file, "#define MUST_USE_RES").unwrap();
+       writeln!(header_file, "#endif").unwrap();
+       writeln!(header_file, "#if defined(__clang__)").unwrap();
+       writeln!(header_file, "#define NONNULL_PTR _Nonnull").unwrap();
+       writeln!(header_file, "#else").unwrap();
+       writeln!(header_file, "#define NONNULL_PTR").unwrap();
+       writeln!(header_file, "#endif").unwrap();
        writeln!(cpp_header_file, "#include <string.h>\nnamespace LDK {{").unwrap();
 
        // First parse the full crate's ASTs, caching them so that we can hold references to the AST
@@ -1566,7 +1581,8 @@ fn main() {
        // ...then walk the ASTs tracking what types we will map, and how, so that we can resolve them
        // when parsing other file ASTs...
        let mut libtypes = CrateTypes { traits: HashMap::new(), opaques: HashMap::new(), mirrored_enums: HashMap::new(),
-               type_aliases: HashMap::new(), templates_defined: HashMap::default(), template_file: &mut derived_templates };
+               type_aliases: HashMap::new(), templates_defined: HashMap::default(), template_file: &mut derived_templates,
+               clonable_types: HashSet::new() };
        walk_ast(&args[1], "/lib.rs", "".to_string(), &libast, &mut libtypes);
 
        // ... finally, do the actual file conversion/mapping, writing out types as we go.