X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Futil%2Fser_macros.rs;h=247fdf60074dc4ff0bad148bef3c89ae374f26d6;hb=2e33acbd9c5ebd605829859a982822df6e0f1723;hp=92a43b3fde5282fb4420d4981c1e23b3d9bd0e81;hpb=54f8895096ea0babf5116c86df31d51ac6b94a55;p=rust-lightning

diff --git a/lightning/src/util/ser_macros.rs b/lightning/src/util/ser_macros.rs
index 92a43b3f..247fdf60 100644
--- a/lightning/src/util/ser_macros.rs
+++ b/lightning/src/util/ser_macros.rs
@@ -13,6 +13,21 @@
 //! [`Readable`]: crate::util::ser::Readable
 //! [`Writeable`]: crate::util::ser::Writeable
 
+// There are quite a few TLV serialization "types" which behave differently. We currently only
+// publicly document the `optional` and `required` types, not supporting anything else publicly and
+// changing them at will.
+//
+// Some of the other types include:
+//  * (default_value, $default) - reads optionally, reading $default if no TLV is present
+//  * (static_value, $value) - ignores any TLVs, always using $value
+//  * required_vec - reads into a Vec without a length prefix, failing if no TLV is present.
+//  * optional_vec - reads into an Option<Vec> without a length prefix, continuing if no TLV is
+//                   present. Writes from a Vec directly, only if any elements are present. Note
+//                   that the struct deserialization macros return a Vec, not an Option.
+//  * upgradable_option - reads via MaybeReadable.
+//  * upgradable_required - reads via MaybeReadable, requiring a TLV be present but may return None
+//                          if MaybeReadable::read() returns None.
+
 /// Implements serialization for a single TLV record.
 /// This is exported for use by other exported macros, do not use directly.
 #[doc(hidden)]
@@ -29,7 +44,7 @@ macro_rules! _encode_tlv {
 		BigSize($field.serialized_length() as u64).write($stream)?;
 		$field.write($stream)?;
 	};
-	($stream: expr, $type: expr, $field: expr, vec_type) => {
+	($stream: expr, $type: expr, $field: expr, required_vec) => {
 		$crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
 	};
 	($stream: expr, $optional_type: expr, $optional_field: expr, option) => {
@@ -39,6 +54,11 @@ macro_rules! _encode_tlv {
 			field.write($stream)?;
 		}
 	};
+	($stream: expr, $type: expr, $field: expr, optional_vec) => {
+		if !$field.is_empty() {
+			$crate::_encode_tlv!($stream, $type, $field, required_vec);
+		}
+	};
 	($stream: expr, $type: expr, $field: expr, upgradable_required) => {
 		$crate::_encode_tlv!($stream, $type, $field, required);
 	};
@@ -112,7 +132,20 @@ macro_rules! _check_encoded_tlv_order {
 /// [`Writer`]: crate::util::ser::Writer
 #[macro_export]
 macro_rules! encode_tlv_stream {
+	($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => {
+		$crate::_encode_tlv_stream!($stream, {$(($type, $field, $fieldty)),*})
+	}
+}
+
+/// Implementation of [`encode_tlv_stream`].
+/// This is exported for use by other exported macros, do not use directly.
+#[doc(hidden)]
+#[macro_export]
+macro_rules! _encode_tlv_stream {
 	($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}) => { {
+		$crate::_encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* }, &[])
+	} };
+	($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),* $(,)*}, $extra_tlvs: expr) => { {
 		#[allow(unused_imports)]
 		use $crate::{
 			ln::msgs::DecodeError,
@@ -124,6 +157,10 @@ macro_rules! encode_tlv_stream {
 		$(
 			$crate::_encode_tlv!($stream, $type, $field, $fieldty);
 		)*
+		for tlv in $extra_tlvs {
+			let (typ, value): &(u64, Vec<u8>) = tlv;
+			$crate::_encode_tlv!($stream, *typ, *value, required_vec);
+		}
 
 		#[allow(unused_mut, unused_variables, unused_assignments)]
 		#[cfg(debug_assertions)]
@@ -132,8 +169,12 @@ macro_rules! encode_tlv_stream {
 			$(
 				$crate::_check_encoded_tlv_order!(last_seen, $type, $fieldty);
 			)*
+			for tlv in $extra_tlvs {
+				let (typ, _): &(u64, Vec<u8>) = tlv;
+				$crate::_check_encoded_tlv_order!(last_seen, *typ, required_vec);
+			}
 		}
-	} }
+	} };
 }
 
 /// Adds the length of the serialized field to a [`LengthCalculatingWriter`].
@@ -154,7 +195,7 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
 		BigSize(field_len as u64).write(&mut $len).expect("No in-memory data may fail to serialize");
 		$len.0 += field_len;
 	};
-	($len: expr, $type: expr, $field: expr, vec_type) => {
+	($len: expr, $type: expr, $field: expr, required_vec) => {
 		$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
 	};
 	($len: expr, $optional_type: expr, $optional_field: expr, option) => {
@@ -165,9 +206,17 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
 			$len.0 += field_len;
 		}
 	};
+	($len: expr, $type: expr, $field: expr, optional_vec) => {
+		if !$field.is_empty() {
+			$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required_vec);
+		}
+	};
 	($len: expr, $type: expr, $field: expr, (option: $trait: ident $(, $read_arg: expr)?)) => {
 		$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, option);
 	};
+	($len: expr, $type: expr, $field: expr, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
+		$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field.map(|f| $encoding(f)), option);
+	};
 	($len: expr, $type: expr, $field: expr, upgradable_required) => {
 		$crate::_get_varint_length_prefixed_tlv_length!($len, $type, $field, required);
 	};
@@ -182,18 +231,27 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
 #[macro_export]
 macro_rules! _encode_varint_length_prefixed_tlv {
 	($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}) => { {
+		$crate::_encode_varint_length_prefixed_tlv!($stream, {$(($type, $field, $fieldty)),*}, &[])
+	} };
+	($stream: expr, {$(($type: expr, $field: expr, $fieldty: tt)),*}, $extra_tlvs: expr) => { {
+		extern crate alloc;
 		use $crate::util::ser::BigSize;
+		use alloc::vec::Vec;
 		let len = {
 			#[allow(unused_mut)]
 			let mut len = $crate::util::ser::LengthCalculatingWriter(0);
 			$(
 				$crate::_get_varint_length_prefixed_tlv_length!(len, $type, $field, $fieldty);
 			)*
+			for tlv in $extra_tlvs {
+				let (typ, value): &(u64, Vec<u8>) = tlv;
+				$crate::_get_varint_length_prefixed_tlv_length!(len, *typ, *value, required_vec);
+			}
 			len.0
 		};
 		BigSize(len as u64).write($stream)?;
-		$crate::encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* });
-	} }
+		$crate::_encode_tlv_stream!($stream, { $(($type, $field, $fieldty)),* }, $extra_tlvs);
+	} };
 }
 
 /// Errors if there are missing required TLV types between the last seen type and the type currently being processed.
@@ -223,7 +281,10 @@ macro_rules! _check_decoded_tlv_order {
 	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, option) => {{
 		// no-op
 	}};
-	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, vec_type) => {{
+	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, required_vec) => {{
+		$crate::_check_decoded_tlv_order!($last_seen_type, $typ, $type, $field, required);
+	}};
+	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, optional_vec) => {{
 		// no-op
 	}};
 	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, upgradable_required) => {{
@@ -265,12 +326,15 @@ macro_rules! _check_missing_tlv {
 	($last_seen_type: expr, $type: expr, $field: ident, (required: $trait: ident $(, $read_arg: expr)?)) => {{
 		$crate::_check_missing_tlv!($last_seen_type, $type, $field, required);
 	}};
-	($last_seen_type: expr, $type: expr, $field: ident, vec_type) => {{
-		// no-op
+	($last_seen_type: expr, $type: expr, $field: ident, required_vec) => {{
+		$crate::_check_missing_tlv!($last_seen_type, $type, $field, required);
 	}};
 	($last_seen_type: expr, $type: expr, $field: ident, option) => {{
 		// no-op
 	}};
+	($last_seen_type: expr, $type: expr, $field: ident, optional_vec) => {{
+		// no-op
+	}};
 	($last_seen_type: expr, $type: expr, $field: ident, upgradable_required) => {{
 		_check_missing_tlv!($last_seen_type, $type, $field, required)
 	}};
@@ -301,13 +365,17 @@ macro_rules! _decode_tlv {
 	($reader: expr, $field: ident, (required: $trait: ident $(, $read_arg: expr)?)) => {{
 		$field = $trait::read(&mut $reader $(, $read_arg)*)?;
 	}};
-	($reader: expr, $field: ident, vec_type) => {{
+	($reader: expr, $field: ident, required_vec) => {{
 		let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
-		$field = Some(f.0);
+		$field = f.0;
 	}};
 	($reader: expr, $field: ident, option) => {{
 		$field = Some($crate::util::ser::Readable::read(&mut $reader)?);
 	}};
+	($reader: expr, $field: ident, optional_vec) => {{
+		let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
+		$field = Some(f.0);
+	}};
 	// `upgradable_required` indicates we're reading a required TLV that may have been upgraded
 	// without backwards compat. We'll error if the field is missing, and return `Ok(None)` if the
 	// field is present but we can no longer understand it.
@@ -535,7 +603,7 @@ macro_rules! impl_writeable_msg {
 		impl $crate::util::ser::Writeable for $st {
 			fn write<W: $crate::util::ser::Writer>(&self, w: &mut W) -> Result<(), $crate::io::Error> {
 				$( self.$field.write(w)?; )*
-				$crate::encode_tlv_stream!(w, {$(($type, self.$tlvfield, $fieldty)),*});
+				$crate::encode_tlv_stream!(w, {$(($type, self.$tlvfield.as_ref(), $fieldty)),*});
 				Ok(())
 			}
 		}
@@ -672,7 +740,10 @@ macro_rules! _init_tlv_based_struct_field {
 	($field: ident, required) => {
 		$field.0.unwrap()
 	};
-	($field: ident, vec_type) => {
+	($field: ident, required_vec) => {
+		$field
+	};
+	($field: ident, optional_vec) => {
 		$field.unwrap()
 	};
 }
@@ -695,12 +766,18 @@ macro_rules! _init_tlv_field_var {
 	($field: ident, (required: $trait: ident $(, $read_arg: expr)?)) => {
 		$crate::_init_tlv_field_var!($field, required);
 	};
-	($field: ident, vec_type) => {
-		let mut $field = Some(Vec::new());
+	($field: ident, required_vec) => {
+		let mut $field = Vec::new();
 	};
 	($field: ident, option) => {
 		let mut $field = None;
 	};
+	($field: ident, optional_vec) => {
+		let mut $field = Some(Vec::new());
+	};
+	($field: ident, (option, encoding: ($fieldty: ty, $encoding: ident))) => {
+		$crate::_init_tlv_field_var!($field, option);
+	};
 	($field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {
 		$crate::_init_tlv_field_var!($field, option);
 	};
@@ -714,10 +791,13 @@ macro_rules! _init_tlv_field_var {
 
 /// Equivalent to running [`_init_tlv_field_var`] then [`read_tlv_fields`].
 ///
+/// If any unused values are read, their type MUST be specified or else `rustc` will read them as an
+/// `i64`.
+///
 /// This is exported for use by other exported macros, do not use directly.
 #[doc(hidden)]
 #[macro_export]
-macro_rules! _init_and_read_tlv_fields {
+macro_rules! _init_and_read_len_prefixed_tlv_fields {
 	($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
 		$(
 			$crate::_init_tlv_field_var!($field, $fieldty);
@@ -729,11 +809,28 @@ macro_rules! _init_and_read_tlv_fields {
 	}
 }
 
+/// Equivalent to running [`_init_tlv_field_var`] then [`decode_tlv_stream`].
+///
+/// If any unused values are read, their type MUST be specified or else `rustc` will read them as an
+/// `i64`.
+macro_rules! _init_and_read_tlv_stream {
+	($reader: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => {
+		$(
+			$crate::_init_tlv_field_var!($field, $fieldty);
+		)*
+
+		$crate::decode_tlv_stream!($reader, {
+			$(($type, $field, $fieldty)),*
+		});
+	}
+}
+
 /// Implements [`Readable`]/[`Writeable`] for a struct storing it as a set of TLVs
 /// If `$fieldty` is `required`, then `$field` is a required field that is not an [`Option`] nor a [`Vec`].
 /// If `$fieldty` is `(default_value, $default)`, then `$field` will be set to `$default` if not present.
 /// If `$fieldty` is `option`, then `$field` is optional field.
-/// If `$fieldty` is `vec_type`, then `$field` is a [`Vec`], which needs to have its individual elements serialized.
+/// If `$fieldty` is `optional_vec`, then `$field` is a [`Vec`], which needs to have its individual elements serialized.
+///    Note that for `optional_vec` no bytes are written if the vec is empty
 ///
 /// For example,
 /// ```
@@ -749,7 +846,7 @@ macro_rules! _init_and_read_tlv_fields {
 /// 	(0, tlv_integer, required),
 /// 	(1, tlv_default_integer, (default_value, 7)),
 /// 	(2, tlv_optional_integer, option),
-/// 	(3, tlv_vec_type_integer, vec_type),
+/// 	(3, tlv_vec_type_integer, optional_vec),
 /// });
 /// ```
 ///
@@ -785,7 +882,7 @@ macro_rules! impl_writeable_tlv_based {
 
 		impl $crate::util::ser::Readable for $st {
 			fn read<R: $crate::io::Read>(reader: &mut R) -> Result<Self, $crate::ln::msgs::DecodeError> {
-				$crate::_init_and_read_tlv_fields!(reader, {
+				$crate::_init_and_read_len_prefixed_tlv_fields!(reader, {
 					$(($type, $field, $fieldty)),*
 				});
 				Ok(Self {
@@ -909,7 +1006,7 @@ macro_rules! _impl_writeable_tlv_based_enum_common {
 /// ```ignore
 /// impl_writeable_tlv_based_enum!(EnumName,
 ///   (0, StructVariantA) => {(0, required_variant_field, required), (1, optional_variant_field, option)},
-///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, vec_type)};
+///   (1, StructVariantB) => {(0, variant_field_a, required), (1, variant_field_b, required), (2, variant_vec_field, optional_vec)};
 ///   (2, TupleVariantA), (3, TupleVariantB),
 /// );
 /// ```
@@ -937,7 +1034,7 @@ macro_rules! impl_writeable_tlv_based_enum {
 						// Because read_tlv_fields creates a labeled loop, we cannot call it twice
 						// in the same function body. Instead, we define a closure and call it.
 						let f = || {
-							$crate::_init_and_read_tlv_fields!(reader, {
+							$crate::_init_and_read_len_prefixed_tlv_fields!(reader, {
 								$(($type, $field, $fieldty)),*
 							});
 							Ok($st::$variant_name {
@@ -949,7 +1046,7 @@ macro_rules! impl_writeable_tlv_based_enum {
 						f()
 					}),*
 					$($tuple_variant_id => {
-						Ok($st::$tuple_variant_name(Readable::read(reader)?))
+						Ok($st::$tuple_variant_name($crate::util::ser::Readable::read(reader)?))
 					}),*
 					_ => {
 						Err($crate::ln::msgs::DecodeError::UnknownRequiredFeature)
@@ -991,7 +1088,7 @@ macro_rules! impl_writeable_tlv_based_enum_upgradable {
 						// Because read_tlv_fields creates a labeled loop, we cannot call it twice
 						// in the same function body. Instead, we define a closure and call it.
 						let f = || {
-							$crate::_init_and_read_tlv_fields!(reader, {
+							$crate::_init_and_read_len_prefixed_tlv_fields!(reader, {
 								$(($type, $field, $fieldty)),*
 							});
 							Ok(Some($st::$variant_name {