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
+ let mut generated_fields = Vec::new(); // Every field's (name, Option<clone_fn>) except this_arg, used in Clone generation
for item in t.items.iter() {
match item {
&syn::TraitItem::Method(ref m) => {
// 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));
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<extern \"C\" fn(&{})>,", m.sig.ident, trait_name).unwrap();
- generated_fields.push((format!("set_{}", m.sig.ident), true));
+ generated_fields.push((format!("set_{}", m.sig.ident), None));
// Note that cbindgen will now generate
// typedef struct Thing {..., set_thing: (const struct Thing*), ...} Thing;
// which does not compile since Thing is not defined before it is used.
}
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));
write_method_params(w, &m.sig, "c_void", types, Some(&meth_gen_types), true, false);
writeln!(w, ",").unwrap();
},
}
}
// 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<extern \"C\" fn (this_arg: *const c_void) -> *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<extern \"C\" fn (new_{}: &mut {})>,", trait_name, trait_name).unwrap();
+ generated_fields.push(("cloned".to_owned(), 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();
writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: &{}) -> bool,", trait_name).unwrap();
- generated_fields.push(("eq".to_owned(), true));
+ generated_fields.push(("eq".to_owned(), None));
},
("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();
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));
},
("Send", _) => {}, ("Sync", _) => {},
(s, i) => {
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) // 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 })
});
}
) );
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<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
- generated_fields.push(("free".to_owned(), true));
+ generated_fields.push(("free".to_owned(), None));
writeln!(w, "}}").unwrap();
macro_rules! impl_trait_for_c {
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", _) => {
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();
}
}
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", _) => {},
}
}
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);
}
_ => 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"]) {
projects / ldk-c-bindings / commitdiff