writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap();
writeln!(w, "}}").unwrap();
writeln!(w, "#[no_mangle]").unwrap();
+ writeln!(w, "pub(crate) extern \"C\" fn {}_write_void(obj: *const c_void) -> crate::c_types::derived::CVec_u8Z {{", struct_for).unwrap();
+ writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &*(obj as *const native{}) }})", struct_for).unwrap();
+ writeln!(w, "}}").unwrap();
+ writeln!(w, "#[no_mangle]").unwrap();
writeln!(w, "pub extern \"C\" fn {}_read(ser: crate::c_types::u8slice) -> {} {{", struct_for, struct_for).unwrap();
writeln!(w, "\tif let Ok(res) = crate::c_types::deserialize_obj(ser) {{").unwrap();
writeln!(w, "\t\t{} {{ inner: Box::into_raw(Box::new(res)), is_owned: true }}", struct_for).unwrap();
writeln!(w, "pub extern \"C\" fn {}_write(obj: *const {}) -> crate::c_types::derived::CVec_u8Z {{", for_obj, for_obj).unwrap();
writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &(*(*obj).inner) }})").unwrap();
writeln!(w, "}}").unwrap();
+ writeln!(w, "#[no_mangle]").unwrap();
+ writeln!(w, "pub(crate) extern \"C\" fn {}_write_void(obj: *const c_void) -> crate::c_types::derived::CVec_u8Z {{", for_obj).unwrap();
+ writeln!(w, "\tcrate::c_types::serialize_obj(unsafe {{ &*(obj as *const native{}) }})", for_obj).unwrap();
+ writeln!(w, "}}").unwrap();
},
"util::ser::Readable" => {
writeln!(w, "#[no_mangle]").unwrap();
}
}
+/// Convert "TraitA : TraitB" to a single function name and return type.
+///
+/// This is (obviously) somewhat over-specialized and only useful for TraitB's that only require a
+/// single function (eg for serialization).
+fn convert_trait_impl_field(trait_path: &str) -> (String, &'static str) {
+ match trait_path {
+ "util::ser::Writeable" => ("write".to_owned(), "crate::c_types::derived::CVec_u8Z"),
+ _ => unimplemented!(),
+ }
+}
+
+/// Companion to convert_trait_impl_field, write an assignment for the function defined by it for
+/// `for_obj` which implements the the trait at `trait_path`.
+fn write_trait_impl_field_assign<W: std::io::Write>(w: &mut W, trait_path: &str, for_obj: &syn::Ident) {
+ match trait_path {
+ "util::ser::Writeable" => {
+ writeln!(w, "\t\twrite: {}_write_void,", for_obj).unwrap();
+ },
+ _ => unimplemented!(),
+ }
+}
+
+/// Write out the impl block for a defined trait struct which has a supertrait
+fn do_write_impl_trait<W: std::io::Write>(w: &mut W, trait_path: &str, trait_name: &syn::Ident, for_obj: &str) {
+ match trait_path {
+ "util::events::MessageSendEventsProvider" => {
+ writeln!(w, "impl lightning::{} for {} {{", trait_path, for_obj).unwrap();
+ writeln!(w, "\tfn get_and_clear_pending_msg_events(&self) -> Vec<lightning::util::events::MessageSendEvent> {{").unwrap();
+ writeln!(w, "\t\t<crate::{} as lightning::{}>::get_and_clear_pending_msg_events(&self.{})", trait_path, trait_path, trait_name).unwrap();
+ writeln!(w, "\t}}\n}}").unwrap();
+ },
+ "util::ser::Writeable" => {
+ writeln!(w, "impl lightning::{} for {} {{", trait_path, for_obj).unwrap();
+ writeln!(w, "\tfn write<W: lightning::util::ser::Writer>(&self, w: &mut W) -> Result<(), ::std::io::Error> {{").unwrap();
+ writeln!(w, "\t\tlet vec = (self.write)(self.this_arg);").unwrap();
+ writeln!(w, "\t\tw.write_all(vec.as_slice())").unwrap();
+ writeln!(w, "\t}}\n}}").unwrap();
+ },
+ _ => panic!(),
+ }
+}
+
// *******************************
// *** Per-Type Printing Logic ***
// *******************************
if supertrait.paren_token.is_some() || supertrait.lifetimes.is_some() {
unimplemented!();
}
- if let Some(ident) = supertrait.path.get_ident() {
- match (&format!("{}", ident) as &str, &ident) {
+ // 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, )*
}
- } else {
- let path = $types.resolve_path(&supertrait.path, None);
- match (&path as &str, &supertrait.path.segments.iter().last().unwrap().ident) {
+ } else if let Some(ident) = supertrait.path.get_ident() {
+ match (&format!("{}", ident) as &str, &ident) {
$( $pat => $e, )*
}
+ } else {
+ panic!("Supertrait unresolvable and not single-ident");
}
},
syn::TypeParamBound::Lifetime(_) => unimplemented!(),
}
} } }
-/// Gets a HashMap from name idents to the bounding trait for associated types.
-/// eg if a native trait has a "type T = TraitA", this will return a HashMap containing a mapping
-/// from "T" to "TraitA".
-fn learn_associated_types<'a>(t: &'a syn::ItemTrait) -> HashMap<&'a syn::Ident, &'a syn::Ident> {
- let mut associated_types = HashMap::new();
- for item in t.items.iter() {
- match item {
- &syn::TraitItem::Type(ref t) => {
- if t.default.is_some() || t.generics.lt_token.is_some() { unimplemented!(); }
- let mut bounds_iter = t.bounds.iter();
- match bounds_iter.next().unwrap() {
- syn::TypeParamBound::Trait(tr) => {
- assert_simple_bound(&tr);
- associated_types.insert(&t.ident, assert_single_path_seg(&tr.path));
- },
- _ => unimplemented!(),
- }
- if bounds_iter.next().is_some() { unimplemented!(); }
- },
- _ => {},
- }
- }
- associated_types
-}
-
/// Prints a C-mapped trait object containing a void pointer and a jump table for each function in
/// the original trait.
/// Implements the native Rust trait and relevant parent traits for the new C-mapped trait.
let mut gen_types = GenericTypes::new();
assert!(gen_types.learn_generics(&t.generics, types));
+ gen_types.learn_associated_types(&t, types);
writeln!(w, "#[repr(C)]\npub struct {} {{", trait_name).unwrap();
writeln!(w, "\tpub this_arg: *mut c_void,").unwrap();
- let associated_types = learn_associated_types(t);
let mut generated_fields = Vec::new(); // Every field's name except this_arg, used in Clone generation
for item in t.items.iter() {
match item {
write!(w, "\tpub {}: extern \"C\" fn (", m.sig.ident).unwrap();
generated_fields.push(format!("{}", m.sig.ident));
- write_method_params(w, &m.sig, &associated_types, "c_void", types, Some(&gen_types), true, false);
+ write_method_params(w, &m.sig, "c_void", types, Some(&gen_types), true, false);
writeln!(w, ",").unwrap();
gen_types.pop_ctx();
generated_fields.push("clone".to_owned());
},
("std::cmp::Eq", _) => {
- writeln!(w, "\tpub eq: extern \"C\" fn (this_arg: *const c_void, other_arg: *const c_void) -> bool,").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());
},
("std::hash::Hash", _) => {
},
("Send", _) => {}, ("Sync", _) => {},
(s, i) => {
- // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
- if types.crate_types.traits.get(s).is_none() { unimplemented!(); }
- writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
- generated_fields.push(format!("{}", i));
+ generated_fields.push(if types.crate_types.traits.get(s).is_none() {
+ let (name, ret) = convert_trait_impl_field(s);
+ writeln!(w, "\tpub {}: extern \"C\" fn (this_arg: *const c_void) -> {},", name, ret).unwrap();
+ name
+ } else {
+ // For in-crate supertraits, just store a C-mapped copy of the supertrait as a member.
+ writeln!(w, "\tpub {}: crate::{},", i, s).unwrap();
+ format!("{}", i)
+ });
}
) );
writeln!(w, "\tpub free: Option<extern \"C\" fn(this_arg: *mut c_void)>,").unwrap();
("std::cmp::Eq", _) => {
writeln!(w, "impl std::cmp::Eq for {} {{}}", trait_name).unwrap();
writeln!(w, "impl std::cmp::PartialEq for {} {{", trait_name).unwrap();
- writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o.this_arg) }}\n}}").unwrap();
+ writeln!(w, "\tfn eq(&self, o: &Self) -> bool {{ (self.eq)(self.this_arg, o) }}\n}}").unwrap();
},
("std::hash::Hash", _) => {
writeln!(w, "impl std::hash::Hash for {} {{", trait_name).unwrap();
writeln!(w, "\tfn hash<H: std::hash::Hasher>(&self, hasher: &mut H) {{ hasher.write_u64((self.hash)(self.this_arg)) }}\n}}").unwrap();
},
("Clone", _) => {
- writeln!(w, "impl Clone for {} {{", trait_name).unwrap();
- writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
- writeln!(w, "\t\tSelf {{").unwrap();
- writeln!(w, "\t\tthis_arg: if let Some(f) = self.clone {{ (f)(self.this_arg) }} else {{ self.this_arg }},").unwrap();
+ writeln!(w, "#[no_mangle]").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 in generated_fields.iter() {
- writeln!(w, "\t\t\t{}: self.{}.clone(),", field, field).unwrap();
+ writeln!(w, "\t\t{}: orig.{}.clone(),", field, field).unwrap();
}
- writeln!(w, "\t\t}}\n\t}}\n}}").unwrap();
+ writeln!(w, "\t}}\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();
+ writeln!(w, "\t}}\n}}").unwrap();
},
(s, i) => {
- if s != "util::events::MessageSendEventsProvider" { unimplemented!(); }
- // XXX: We straight-up cheat here - instead of bothering to get the trait object we
- // just print what we need since this is only used in one place.
- writeln!(w, "impl lightning::{} for {} {{", s, trait_name).unwrap();
- writeln!(w, "\tfn get_and_clear_pending_msg_events(&self) -> Vec<lightning::util::events::MessageSendEvent> {{").unwrap();
- writeln!(w, "\t\t<crate::{} as lightning::{}>::get_and_clear_pending_msg_events(&self.{})", s, s, i).unwrap();
- writeln!(w, "\t}}\n}}").unwrap();
+ do_write_impl_trait(w, s, i, &trait_name);
}
) );
}
write_method_var_decl_body(w, &m.sig, "\t", types, Some(&gen_types), true);
write!(w, "(self.{})(", m.sig.ident).unwrap();
- write_method_call_params(w, &m.sig, &associated_types, "\t", types, Some(&gen_types), "", true);
+ write_method_call_params(w, &m.sig, "\t", types, Some(&gen_types), "", true);
writeln!(w, "\n\t}}").unwrap();
gen_types.pop_ctx();
writeln!(w, "#[allow(unused)]").unwrap();
writeln!(w, "/// When moving out of the pointer, we have to ensure we aren't a reference, this makes that easy").unwrap();
writeln!(w, "impl {} {{", struct_name).unwrap();
- writeln!(w, "\tpub(crate) fn take_ptr(mut self) -> *mut native{} {{", struct_name).unwrap();
+ writeln!(w, "\tpub(crate) fn take_inner(mut self) -> *mut native{} {{", struct_name).unwrap();
writeln!(w, "\t\tassert!(self.is_owned);").unwrap();
writeln!(w, "\t\tlet ret = self.inner;").unwrap();
writeln!(w, "\t\tself.inner = std::ptr::null_mut();").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;
}
}
write_cpp_wrapper(cpp_headers, &format!("{}", ident), true);
}
-/// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
-/// the struct itself, and then writing getters and setters for public, understood-type fields and
-/// a constructor if every field is public.
-fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct, types: &mut TypeResolver<'b, 'a>, extra_headers: &mut File, cpp_headers: &mut File) {
- let struct_name = &format!("{}", s.ident);
+fn declare_struct<'a, 'b>(s: &'a syn::ItemStruct, types: &mut TypeResolver<'b, 'a>) -> bool {
let export = export_status(&s.attrs);
match export {
ExportStatus::Export => {},
- ExportStatus::TestOnly => return,
+ ExportStatus::TestOnly => return false,
ExportStatus::NoExport => {
types.struct_ignored(&s.ident);
- return;
+ return false;
}
}
+ types.struct_imported(&s.ident, format!("{}", s.ident));
+ true
+}
+
+/// Writes out all the relevant mappings for a Rust struct, deferring to writeln_opaque to generate
+/// the struct itself, and then writing getters and setters for public, understood-type fields and
+/// a constructor if every field is public.
+fn writeln_struct<'a, 'b, W: std::io::Write>(w: &mut W, s: &'a syn::ItemStruct, types: &mut TypeResolver<'b, 'a>, extra_headers: &mut File, cpp_headers: &mut File) {
+ if !declare_struct(s, types) { return; }
+
+ let struct_name = &format!("{}", s.ident);
writeln_opaque(w, &s.ident, struct_name, &s.generics, &s.attrs, types, extra_headers, cpp_headers);
eprintln!("exporting fields for {}", struct_name);
writeln!(w, "\t}})), is_owned: true }}\n}}").unwrap();
}
}
-
- types.struct_imported(&s.ident, struct_name.clone());
}
/// Prints a relevant conversion for impl *
// That's great, except that they are unresolved idents, so if we learn
// mappings from a trai defined in a different file, we may mis-resolve or
// fail to resolve the mapped types.
- let trait_associated_types = learn_associated_types(trait_obj);
+ gen_types.learn_associated_types(trait_obj, types);
let mut impl_associated_types = HashMap::new();
for item in i.items.iter() {
match item {
ExportStatus::Export => {},
ExportStatus::NoExport|ExportStatus::TestOnly => return,
}
+
+ // For cases where we have a concrete native object which implements a
+ // trait and need to return the C-mapped version of the trait, provide a
+ // From<> implementation which does all the work to ensure free is handled
+ // properly. This way we can call this method from deep in the
+ // type-conversion logic without actually knowing the concrete native type.
+ writeln!(w, "impl From<native{}> for crate::{} {{", ident, full_trait_path).unwrap();
+ writeln!(w, "\tfn from(obj: native{}) -> Self {{", ident).unwrap();
+ writeln!(w, "\t\tlet mut rust_obj = {} {{ inner: Box::into_raw(Box::new(obj)), is_owned: true }};", ident).unwrap();
+ writeln!(w, "\t\tlet mut ret = {}_as_{}(&rust_obj);", ident, trait_obj.ident).unwrap();
+ writeln!(w, "\t\t// We want to free rust_obj when ret gets drop()'d, not rust_obj, so wipe rust_obj's pointer and set ret's free() fn").unwrap();
+ writeln!(w, "\t\trust_obj.inner = std::ptr::null_mut();").unwrap();
+ 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();
writeln!(w, "\tcrate::{} {{", full_trait_path).unwrap();
writeln!(w, "\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
("Clone", _) => {
writeln!(w, "\t\tclone: Some({}_clone_void),", ident).unwrap();
},
+ ("Sync", _) => {}, ("Send", _) => {},
+ ("std::marker::Sync", _) => {}, ("std::marker::Send", _) => {},
(s, t) => {
- if s.starts_with("util::") {
- let supertrait_obj = types.crate_types.traits.get(s).unwrap();
+ if let Some(supertrait_obj) = types.crate_types.traits.get(s) {
writeln!(w, "\t\t{}: crate::{} {{", t, s).unwrap();
writeln!(w, "\t\t\tthis_arg: unsafe {{ (*this_arg).inner as *mut c_void }},").unwrap();
writeln!(w, "\t\t\tfree: None,").unwrap();
}
}
write!(w, "\t\t}},\n").unwrap();
+ } else {
+ write_trait_impl_field_assign(w, s, ident);
}
}
) );
write!(w, "extern \"C\" fn {}_{}_{}(", ident, trait_obj.ident, $m.sig.ident).unwrap();
gen_types.push_ctx();
assert!(gen_types.learn_generics(&$m.sig.generics, types));
- write_method_params(w, &$m.sig, &trait_associated_types, "c_void", types, Some(&gen_types), true, true);
+ write_method_params(w, &$m.sig, "c_void", types, Some(&gen_types), true, true);
write!(w, " {{\n\t").unwrap();
write_method_var_decl_body(w, &$m.sig, "", types, Some(&gen_types), false);
let mut takes_self = false;
},
_ => {},
}
- write_method_call_params(w, &$m.sig, &trait_associated_types, "", types, Some(&gen_types), &real_type, false);
+ write_method_call_params(w, &$m.sig, "", types, Some(&gen_types), &real_type, false);
gen_types.pop_ctx();
write!(w, "\n}}\n").unwrap();
if let syn::ReturnType::Type(_, rtype) = &$m.sig.output {
}
walk_supertraits!(trait_obj, types, (
(s, t) => {
- if s.starts_with("util::") {
+ if let Some(supertrait_obj) = types.crate_types.traits.get(s).cloned() {
writeln!(w, "use {}::{} as native{}Trait;", types.orig_crate, s, t).unwrap();
- let supertrait_obj = *types.crate_types.traits.get(s).unwrap();
for item in supertrait_obj.items.iter() {
match item {
syn::TraitItem::Method(m) => {
};
gen_types.push_ctx();
assert!(gen_types.learn_generics(&m.sig.generics, types));
- write_method_params(w, &m.sig, &HashMap::new(), &ret_type, types, Some(&gen_types), false, true);
+ write_method_params(w, &m.sig, &ret_type, types, Some(&gen_types), false, true);
write!(w, " {{\n\t").unwrap();
write_method_var_decl_body(w, &m.sig, "", types, Some(&gen_types), false);
let mut takes_self = false;
} else {
write!(w, "{}::{}::{}(", types.orig_crate, resolved_path, m.sig.ident).unwrap();
}
- write_method_call_params(w, &m.sig, &HashMap::new(), "", types, Some(&gen_types), &ret_type, false);
+ write_method_call_params(w, &m.sig, "", types, Some(&gen_types), &ret_type, false);
gen_types.pop_ctx();
writeln!(w, "\n}}\n").unwrap();
}
false
}
+fn declare_enum<'a, 'b>(e: &'a syn::ItemEnum, types: &mut TypeResolver<'b, 'a>) {
+ match export_status(&e.attrs) {
+ ExportStatus::Export => {},
+ ExportStatus::NoExport|ExportStatus::TestOnly => return,
+ }
+
+ if is_enum_opaque(e) {
+ types.enum_ignored(&e.ident);
+ } else {
+ types.mirrored_enum_declared(&e.ident);
+ }
+}
+
/// Print a mapping of an enum. If all of the enum's fields are C-mapped in some form (or the enum
/// is unitary), we generate an equivalent enum with all types replaced with their C mapped
/// versions followed by conversion functions which map between the Rust version and the C mapped
if is_enum_opaque(e) {
eprintln!("Skipping enum {} as it contains non-unit fields", e.ident);
writeln_opaque(w, &e.ident, &format!("{}", e.ident), &e.generics, &e.attrs, types, extra_headers, cpp_headers);
- types.enum_ignored(&e.ident);
return;
}
writeln_docs(w, &e.attrs, "");
if e.generics.lt_token.is_some() {
unimplemented!();
}
- types.mirrored_enum_declared(&e.ident);
let mut needs_free = false;
if needs_free {
writeln!(w, "#[no_mangle]\npub extern \"C\" fn {}_free(this_ptr: {}) {{ }}", e.ident, e.ident).unwrap();
}
+ writeln!(w, "#[no_mangle]").unwrap();
+ 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);
}
if !gen_types.learn_generics(&f.sig.generics, types) { return; }
write!(w, "#[no_mangle]\npub extern \"C\" fn {}(", f.sig.ident).unwrap();
- write_method_params(w, &f.sig, &HashMap::new(), "", types, Some(&gen_types), false, true);
+ write_method_params(w, &f.sig, "", types, Some(&gen_types), false, true);
write!(w, " {{\n\t").unwrap();
write_method_var_decl_body(w, &f.sig, "", types, Some(&gen_types), false);
write!(w, "{}::{}::{}(", types.orig_crate, types.module_path, f.sig.ident).unwrap();
- write_method_call_params(w, &f.sig, &HashMap::new(), "", types, Some(&gen_types), "", false);
+ write_method_call_params(w, &f.sig, "", types, Some(&gen_types), "", false);
writeln!(w, "\n}}\n").unwrap();
}
let mut type_resolver = TypeResolver::new(orig_crate, module, crate_types);
+ // First pass over the items and fill in imports and file-declared objects in the type resolver
for item in syntax.items.iter() {
match item {
syn::Item::Use(u) => type_resolver.process_use(&mut out, &u),
+ syn::Item::Struct(s) => {
+ if let syn::Visibility::Public(_) = s.vis {
+ declare_struct(&s, &mut type_resolver);
+ }
+ },
+ syn::Item::Enum(e) => {
+ if let syn::Visibility::Public(_) = e.vis {
+ declare_enum(&e, &mut type_resolver);
+ }
+ },
+ _ => {},
+ }
+ }
+
+ for item in syntax.items.iter() {
+ match item {
+ syn::Item::Use(_) => {}, // Handled above
syn::Item::Static(_) => {},
syn::Item::Enum(e) => {
if let syn::Visibility::Public(_) = e.vis {
projects / rust-lightning / blobdiff