From: Matt Corallo <git@bluematt.me>
Date: Tue, 5 Jan 2021 00:26:12 +0000 (-0500)
Subject: [bindings] Move to manual write-out for Vec, too
X-Git-Tag: v0.0.13~32^2~6
X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=commitdiff_plain;h=7dd9d6f40cc5c7d251cc45820e350f669e3e1dfb;p=rust-lightning

[bindings] Move to manual write-out for Vec, too
---

diff --git a/c-bindings-gen/src/blocks.rs b/c-bindings-gen/src/blocks.rs
index 9ae0dab2..64cb163d 100644
--- a/c-bindings-gen/src/blocks.rs
+++ b/c-bindings-gen/src/blocks.rs
@@ -172,6 +172,55 @@ pub fn write_result_block<W: std::io::Write>(w: &mut W, mangled_container: &str,
 	}
 }
 
+/// Writes out a C-callable concrete Vec<A> struct and utility methods
+pub fn write_vec_block<W: std::io::Write>(w: &mut W, mangled_container: &str, inner_type: &str, clonable: bool) {
+	writeln!(w, "#[repr(C)]").unwrap();
+	writeln!(w, "pub struct {} {{", mangled_container).unwrap();
+	writeln!(w, "\tpub data: *mut {},", inner_type).unwrap();
+	writeln!(w, "\tpub datalen: usize").unwrap();
+	writeln!(w, "}}").unwrap();
+
+	writeln!(w, "impl {} {{", mangled_container).unwrap();
+	writeln!(w, "\t#[allow(unused)] pub(crate) fn into_rust(&mut self) -> Vec<{}> {{", inner_type).unwrap();
+	writeln!(w, "\t\tif self.datalen == 0 {{ return Vec::new(); }}").unwrap();
+	writeln!(w, "\t\tlet ret = unsafe {{ Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) }}.into();").unwrap();
+	writeln!(w, "\t\tself.data = std::ptr::null_mut();").unwrap();
+	writeln!(w, "\t\tself.datalen = 0;").unwrap();
+	writeln!(w, "\t\tret").unwrap();
+	writeln!(w, "\t}}").unwrap();
+	writeln!(w, "\t#[allow(unused)] pub(crate) fn as_slice(&self) -> &[{}] {{", inner_type).unwrap();
+	writeln!(w, "\t\tunsafe {{ std::slice::from_raw_parts_mut(self.data, self.datalen) }}").unwrap();
+	writeln!(w, "\t}}").unwrap();
+	writeln!(w, "}}").unwrap();
+
+	writeln!(w, "impl From<Vec<{}>> for {} {{", inner_type, mangled_container).unwrap();
+	writeln!(w, "\tfn from(v: Vec<{}>) -> Self {{", inner_type).unwrap();
+	writeln!(w, "\t\tlet datalen = v.len();").unwrap();
+	writeln!(w, "\t\tlet data = Box::into_raw(v.into_boxed_slice());").unwrap();
+	writeln!(w, "\t\tSelf {{ datalen, data: unsafe {{ (*data).as_mut_ptr() }} }}").unwrap();
+	writeln!(w, "\t}}").unwrap();
+	writeln!(w, "}}").unwrap();
+
+	writeln!(w, "#[no_mangle]").unwrap();
+	writeln!(w, "pub extern \"C\" fn {}_free(_res: {}) {{ }}", mangled_container, mangled_container).unwrap();
+	writeln!(w, "impl Drop for {} {{", mangled_container).unwrap();
+	writeln!(w, "\tfn drop(&mut self) {{").unwrap();
+	writeln!(w, "\t\tif self.datalen == 0 {{ return; }}").unwrap();
+	writeln!(w, "\t\tunsafe {{ Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) }};").unwrap();
+	writeln!(w, "\t}}").unwrap();
+	writeln!(w, "}}").unwrap();
+	if clonable {
+		writeln!(w, "impl Clone for {} {{", mangled_container).unwrap();
+		writeln!(w, "\tfn clone(&self) -> Self {{").unwrap();
+		writeln!(w, "\t\tlet mut res = Vec::new();").unwrap();
+		writeln!(w, "\t\tif self.datalen == 0 {{ return Self::from(res); }}").unwrap();
+		writeln!(w, "\t\tres.extend_from_slice(unsafe {{ std::slice::from_raw_parts_mut(self.data, self.datalen) }});").unwrap();
+		writeln!(w, "\t\tSelf::from(res)").unwrap();
+		writeln!(w, "\t}}").unwrap();
+		writeln!(w, "}}").unwrap();
+	}
+}
+
 /// Prints the docs from a given attribute list unless its tagged no export
 pub fn writeln_docs<W: std::io::Write>(w: &mut W, attrs: &[syn::Attribute], prefix: &str) {
 	for attr in attrs.iter() {
diff --git a/c-bindings-gen/src/types.rs b/c-bindings-gen/src/types.rs
index 7e781a03..ab85f7b4 100644
--- a/c-bindings-gen/src/types.rs
+++ b/c-bindings-gen/src/types.rs
@@ -1796,24 +1796,14 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> {
 					write!(w, "{}", resolved_generic).unwrap();
 				} else if let Some(c_type) = self.c_type_from_path(&resolved_generic, is_ref, false) {
 					if self.is_known_container(&resolved_generic, is_ref) {
-						if resolved_generic == "Result" {
-							let mut inner_args = Vec::new();
-							if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments {
-								for arg in args.args.iter() {
-									if let syn::GenericArgument::Type(t) = arg { inner_args.push(t) } else { unimplemented!() };
-								}
-							} else { unimplemented!(); }
-							self.write_c_mangled_container_path(w, inner_args, generics, &resolved_generic, is_ref, false, false);
-						} else {
-							write!(w, "{}::C{}Templ<", Self::container_templ_path(), single_ident_generic_path_to_ident(&p_arg.path).unwrap()).unwrap();
-							assert_eq!(p_arg.path.segments.len(), 1);
-							if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments {
-								self.write_template_generics(w, &mut args.args.iter().map(|gen|
-									if let syn::GenericArgument::Type(t) = gen { t } else { unimplemented!() }),
-									generics, is_ref, in_crate);
-							} else { unimplemented!(); }
-							write!(w, ">").unwrap();
-						}
+						assert!(resolved_generic == "Vec" || resolved_generic == "Result");
+						let mut inner_args = Vec::new();
+						if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments {
+							for arg in args.args.iter() {
+								if let syn::GenericArgument::Type(t) = arg { inner_args.push(t) } else { unimplemented!() };
+							}
+						} else { unimplemented!(); }
+						assert!(self.write_c_mangled_container_path(w, inner_args, generics, &resolved_generic, is_ref, false, false));
 					} else if resolved_generic == "Option" {
 						if let syn::PathArguments::AngleBracketed(args) = &p_arg.path.segments.iter().next().unwrap().arguments {
 							self.write_template_generics(w, &mut args.args.iter().map(|gen|
@@ -1897,6 +1887,15 @@ impl<'a, 'c: 'a> TypeResolver<'a, 'c> {
 				if is_clonable {
 					self.crate_types.clonable_types.insert(Self::generated_container_path().to_owned() + "::" + &mangled_container);
 				}
+			} else if container_type == "Vec" {
+				let mut a_ty: Vec<u8> = Vec::new();
+				self.write_template_generics(&mut a_ty, &mut args.iter().map(|t| *t), generics, is_ref, true);
+				let ty = String::from_utf8(a_ty).unwrap();
+				let is_clonable = self.is_clonable(&ty);
+				write_vec_block(&mut created_container, &mangled_container, &ty, is_clonable);
+				if is_clonable {
+					self.crate_types.clonable_types.insert(Self::generated_container_path().to_owned() + "::" + &mangled_container);
+				}
 			} else {
 				write!(&mut created_container, "pub type {} = ", mangled_container).unwrap();
 				write!(&mut created_container, "{}::C{}Templ<", Self::container_templ_path(), container_type).unwrap();
diff --git a/lightning-c-bindings/src/c_types/mod.rs b/lightning-c-bindings/src/c_types/mod.rs
index 5f8eb258..76807621 100644
--- a/lightning-c-bindings/src/c_types/mod.rs
+++ b/lightning-c-bindings/src/c_types/mod.rs
@@ -128,7 +128,7 @@ impl Transaction {
 impl Drop for Transaction {
 	fn drop(&mut self) {
 		if self.data_is_owned && self.datalen != 0 {
-			let _ = CVecTempl { data: self.data as *mut u8, datalen: self.datalen };
+			let _ = derived::CVec_u8Z { data: self.data as *mut u8, datalen: self.datalen };
 		}
 	}
 }
@@ -157,7 +157,7 @@ impl TxOut {
 	}
 	pub(crate) fn from_rust(txout: ::bitcoin::blockdata::transaction::TxOut) -> Self {
 		Self {
-			script_pubkey: CVecTempl::from(txout.script_pubkey.into_bytes()),
+			script_pubkey: derived::CVec_u8Z::from(txout.script_pubkey.into_bytes()),
 			value: txout.value
 		}
 	}
@@ -223,7 +223,7 @@ impl lightning::util::ser::Writer for VecWriter {
 pub(crate) fn serialize_obj<I: lightning::util::ser::Writeable>(i: &I) -> derived::CVec_u8Z {
 	let mut out = VecWriter(Vec::new());
 	i.write(&mut out).unwrap();
-	CVecTempl::from(out.0)
+	derived::CVec_u8Z::from(out.0)
 }
 pub(crate) fn deserialize_obj<I: lightning::util::ser::Readable>(s: u8slice) -> Result<I, lightning::ln::msgs::DecodeError> {
 	I::read(&mut s.to_slice())
@@ -298,46 +298,6 @@ impl<O, E> Drop for CResultTempl<O, E> {
 	}
 }
 
-#[repr(C)]
-pub struct CVecTempl<T> {
-	pub data: *mut T,
-	pub datalen: usize
-}
-impl<T> CVecTempl<T> {
-	pub(crate) fn into_rust(&mut self) -> Vec<T> {
-		if self.datalen == 0 { return Vec::new(); }
-		let ret = unsafe { Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) }.into();
-		self.data = std::ptr::null_mut();
-		self.datalen = 0;
-		ret
-	}
-	pub(crate) fn as_slice(&self) -> &[T] {
-		unsafe { std::slice::from_raw_parts_mut(self.data, self.datalen) }
-	}
-}
-impl<T> From<Vec<T>> for CVecTempl<T> {
-	fn from(v: Vec<T>) -> Self {
-		let datalen = v.len();
-		let data = Box::into_raw(v.into_boxed_slice());
-		CVecTempl { datalen, data: unsafe { (*data).as_mut_ptr() } }
-	}
-}
-pub extern "C" fn CVecTempl_free<T>(_res: CVecTempl<T>) { }
-impl<T> Drop for CVecTempl<T> {
-	fn drop(&mut self) {
-		if self.datalen == 0 { return; }
-		unsafe { Box::from_raw(std::slice::from_raw_parts_mut(self.data, self.datalen)) };
-	}
-}
-impl<T: Clone> Clone for CVecTempl<T> {
-	fn clone(&self) -> Self {
-		let mut res = Vec::new();
-		if self.datalen == 0 { return Self::from(res); }
-		res.extend_from_slice(unsafe { std::slice::from_raw_parts_mut(self.data, self.datalen) });
-		Self::from(res)
-	}
-}
-
 #[repr(C)]
 pub struct C2TupleTempl<A, B> {
 	pub a: A,