From cb112c83bfa1291e43c0c260dbc5b78298699e69 Mon Sep 17 00:00:00 2001 From: Matt Corallo Date: Fri, 14 May 2021 17:00:10 +0000 Subject: [PATCH] Create mappings for std::hasher::Hash and std::cmp::Eq --- c-bindings-gen/src/main.rs | 46 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 46 insertions(+) diff --git a/c-bindings-gen/src/main.rs b/c-bindings-gen/src/main.rs index 4d0bf58..7f95ef8 100644 --- a/c-bindings-gen/src/main.rs +++ b/c-bindings-gen/src/main.rs @@ -949,6 +949,52 @@ fn writeln_impl(w: &mut W, i: &syn::ItemImpl, types: &mut Typ write!(w, "\t{} {{ inner: Box::into_raw(Box::new(Default::default())), is_owned: true }}\n", ident).unwrap(); write!(w, "}}\n").unwrap(); } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "PartialEq"]) { + } else if path_matches_nongeneric(&trait_path.1, &["core", "cmp", "Eq"]) { + writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap(); + writeln!(w, "/// This ignores pointers and is_owned flags and looks at the values in fields.").unwrap(); + if types.c_type_has_inner_from_path(&resolved_path) { + writeln!(w, "/// Two objects with NULL inner values will be considered \"equal\" here.").unwrap(); + } + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_eq(a: &{}, b: &{}) -> bool {{\n", ident, ident, ident).unwrap(); + if types.c_type_has_inner_from_path(&resolved_path) { + write!(w, "\tif a.inner == b.inner {{ return true; }}\n").unwrap(); + write!(w, "\tif a.inner.is_null() || b.inner.is_null() {{ return false; }}\n").unwrap(); + } + + let path = &p.path; + let ref_type: syn::Type = syn::parse_quote!(&#path); + 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"); + + write!(w, "\tif ").unwrap(); + types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types)); + write!(w, "a").unwrap(); + types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types)); + write!(w, " == ").unwrap(); + types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types)); + write!(w, "b").unwrap(); + types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types)); + + writeln!(w, " {{ true }} else {{ false }}\n}}").unwrap(); + } else if path_matches_nongeneric(&trait_path.1, &["core", "hash", "Hash"]) { + writeln!(w, "/// Checks if two {}s contain equal inner contents.", ident).unwrap(); + write!(w, "#[no_mangle]\npub extern \"C\" fn {}_hash(o: &{}) -> u64 {{\n", ident, ident).unwrap(); + if types.c_type_has_inner_from_path(&resolved_path) { + write!(w, "\tif o.inner.is_null() {{ return 0; }}\n").unwrap(); + } + + let path = &p.path; + let ref_type: syn::Type = syn::parse_quote!(&#path); + 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"); + + writeln!(w, "\t// Note that we'd love to use std::collections::hash_map::DefaultHasher but it's not in core").unwrap(); + writeln!(w, "\t#[allow(deprecated)]").unwrap(); + writeln!(w, "\tlet mut hasher = core::hash::SipHasher::new();").unwrap(); + write!(w, "\tstd::hash::Hash::hash(").unwrap(); + types.write_from_c_conversion_prefix(w, &ref_type, Some(&gen_types)); + write!(w, "o").unwrap(); + types.write_from_c_conversion_suffix(w, &ref_type, Some(&gen_types)); + writeln!(w, ", &mut hasher);").unwrap(); + writeln!(w, "\tstd::hash::Hasher::finish(&hasher)\n}}").unwrap(); } else if (path_matches_nongeneric(&trait_path.1, &["core", "clone", "Clone"]) || path_matches_nongeneric(&trait_path.1, &["Clone"])) && types.c_type_has_inner_from_path(&resolved_path) { writeln!(w, "impl Clone for {} {{", ident).unwrap(); -- 2.30.2