Check if types are understood before we map an impl block for them

[ldk-c-bindings] / c-bindings-gen / src / main.rs

diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs
index d490a8901d363b53b7f83481de7c9844aeb6e20a..b88f37ffe9e306cc0ac83b5abfaa16d7118e0af1 100644 (file)
--- a/c-bindings-gen/src/main.rs
+++ b/c-bindings-gen/src/main.rs
@@ -592,7 +592,7 @@ fn writeln_opaque<W: std::io::Write>(w: &mut W, ident: &syn::Ident, struct_name:
        // If we directly read the original type by its original name, cbindgen hits
        // https://github.com/eqrion/cbindgen/issues/286 Thus, instead, we import it as a temporary
        // name and then reference it by that name, which works around the issue.
-       write!(w, "\nuse {}::{} as native{}Import;\ntype native{} = native{}Import", types.module_path, ident, ident, ident, ident).unwrap();
+       write!(w, "\nuse {}::{} as native{}Import;\npub(crate) type native{} = native{}Import", types.module_path, ident, ident, ident, ident).unwrap();
        maybe_write_generics(w, &generics, &types, true);
        writeln!(w, ";\n").unwrap();
        writeln!(extra_headers, "struct native{}Opaque;\ntypedef struct native{}Opaque LDKnative{};", ident, ident, ident).unwrap();
@@ -614,7 +614,7 @@ fn writeln_opaque<W: std::io::Write>(w: &mut W, ident: &syn::Ident, struct_name:
        writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_obj: {}) {{ }}", struct_name, struct_name).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, "extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
+       writeln!(w, "pub(crate) extern \"C\" fn {}_free_void(this_ptr: *mut c_void) {{", struct_name).unwrap();
        writeln!(w, "\tunsafe {{ let _ = Box::from_raw(this_ptr as *mut native{}); }}\n}}", struct_name).unwrap();
        writeln!(w, "#[allow(unused)]").unwrap();
        writeln!(w, "impl {} {{", struct_name).unwrap();
@@ -771,6 +771,11 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                if p.qself.is_some() { unimplemented!(); }
                if let Some(ident) = single_ident_generic_path_to_ident(&p.path) {
                        if let Some(resolved_path) = types.maybe_resolve_non_ignored_ident(&ident) {
+                               if !types.understood_c_path(&p.path) {
+                                       eprintln!("Not implementing anything for impl {} as the type is not understood (probably C-not exported)", ident);
+                                       return;
+                               }
+
                                let mut gen_types = GenericTypes::new(Some(resolved_path.clone()));
                                if !gen_types.learn_generics(&i.generics, types) {
                                        eprintln!("Not implementing anything for impl {} due to not understood generics", ident);
@@ -829,7 +834,13 @@ fn writeln_impl<W: std::io::Write>(w: &mut W, i: &syn::ItemImpl, types: &mut Typ
                                                // properly. This way we can call this method from deep in the
                                                // type-conversion logic without actually knowing the concrete native type.
                                                if !resolved_path.starts_with(types.module_path) {
-                                                       writeln!(w, "use {} as native{};", resolved_path, ident).unwrap();
+                                                       if !first_seg_is_stdlib(resolved_path.split("::").next().unwrap()) {
+                                                               writeln!(w, "use crate::{}::native{} as native{};", resolved_path.rsplitn(2, "::").skip(1).next().unwrap(), ident, ident).unwrap();
+                                                               writeln!(w, "use crate::{};", resolved_path).unwrap();
+                                                               writeln!(w, "use crate::{}_free_void;", resolved_path).unwrap();
+                                                       } else {
+                                                               writeln!(w, "use {} as native{};", resolved_path, ident).unwrap();
+                                                       }
                                                }
                                                writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
                                                writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();