f drop read-side expr

Author: TheBlueMatt

lightning/src/util/ser_macros.rs

@@ -54,7 +54,7 @@ macro_rules! _encode_tlv {
 			field.write($stream)?;
 		}
 	};
-	($stream: expr, $optional_type: expr, $optional_field: expr, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {
+	($stream: expr, $optional_type: expr, $optional_field: expr, (legacy, $fieldty: ty, $write: expr)) => {
 		$crate::_encode_tlv!($stream, $optional_type, $write, option);
 	};
 	($stream: expr, $type: expr, $field: expr, optional_vec) => {
@@ -216,7 +216,7 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
 			$len.0 += field_len;
 		}
 	};
-	($len: expr, $optional_type: expr, $optional_field: expr, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {
+	($len: expr, $optional_type: expr, $optional_field: expr, (legacy, $fieldty: ty, $write: expr)) => {
 		$crate::_get_varint_length_prefixed_tlv_length!($len, $optional_type, $write, option);
 	};
 	($len: expr, $type: expr, $field: expr, optional_vec) => {
@@ -301,7 +301,7 @@ macro_rules! _check_decoded_tlv_order {
 	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (option, explicit_type: $fieldty: ty)) => {{
 		// no-op
 	}};
-	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {{
+	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (legacy, $fieldty: ty, $write: expr)) => {{
 		// no-op
 	}};
 	($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, (required, explicit_type: $fieldty: ty)) => {{
@@ -363,7 +363,7 @@ macro_rules! _check_missing_tlv {
 	($last_seen_type: expr, $type: expr, $field: ident, (option, explicit_type: $fieldty: ty)) => {{
 		// no-op
 	}};
-	($last_seen_type: expr, $type: expr, $field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {{
+	($last_seen_type: expr, $type: expr, $field: ident, (legacy, $fieldty: ty, $write: expr)) => {{
 		// no-op
 	}};
 	($last_seen_type: expr, $type: expr, $field: ident, (required, explicit_type: $fieldty: ty)) => {{
@@ -413,7 +413,7 @@ macro_rules! _decode_tlv {
 		let _field: &Option<$fieldty> = &$field;
 		_decode_tlv!($outer_reader, $reader, $field, option);
 	}};
-	($outer_reader: expr, $reader: expr, $field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {{
+	($outer_reader: expr, $reader: expr, $field: ident, (legacy, $fieldty: ty, $write: expr)) => {{
 		$crate::_decode_tlv!($outer_reader, $reader, $field, (option, explicit_type: $fieldty));
 		// Note that $read is only executed in impl_writeable_tlv_based_enum_upgradable!
 	}};
@@ -478,16 +478,6 @@ macro_rules! _decode_tlv {
 	}};
 }
 
-/// Runs the read side logic for legacy read types
-#[doc(hidden)]
-#[macro_export]
-macro_rules! _run_legacy_tlv_read_logic {
-	($field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {{
-		$read;
-	}};
-	($field: ident, $fieldty: tt) => {};
-}
-
 /// Checks if `$val` matches `$type`.
 /// This is exported for use by other exported macros, do not use directly.
 #[doc(hidden)]
@@ -569,13 +559,6 @@ macro_rules! decode_tlv_stream_with_custom_tlv_decode {
 #[macro_export]
 macro_rules! _decode_tlv_stream_range {
 	($stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
-	 $(, $decode_custom_tlv: expr)?) => { {
-		$crate::_decode_tlv_stream_range!(SKIP_LEGACY, $stream, $range, $rewind, {$(($type, $field, $fieldty)),*} $(, $decode_custom_tlv)?);
-		$({
-			$crate::_run_legacy_tlv_read_logic!($field, $fieldty);
-		})*
-	} };
-	(SKIP_LEGACY, $stream: expr, $range: expr, $rewind: ident, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}
 	 $(, $decode_custom_tlv: expr)?) => { {
 		use $crate::ln::msgs::DecodeError;
 		let mut last_seen_type: Option<u64> = None;
@@ -818,7 +801,7 @@ macro_rules! _init_tlv_based_struct_field {
 	($field: ident, option) => {
 		$field
 	};
-	($field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {
+	($field: ident, (legacy, $fieldty: ty, $write: expr)) => {
 		$crate::_init_tlv_based_struct_field!($field, option)
 	};
 	($field: ident, (option: $trait: ident $(, $read_arg: expr)?)) => {
@@ -872,7 +855,7 @@ macro_rules! _init_tlv_field_var {
 	($field: ident, (option, explicit_type: $fieldty: ty)) => {
 		let mut $field: Option<$fieldty> = None;
 	};
-	($field: ident, (legacy, $fieldty: ty, $read: expr, $write: expr)) => {
+	($field: ident, (legacy, $fieldty: ty, $write: expr)) => {
 		$crate::_init_tlv_field_var!($field, (option, explicit_type: $fieldty));
 	};
 	($field: ident, (required, explicit_type: $fieldty: ty)) => {
@@ -943,24 +926,12 @@ macro_rules! _ignore_arg {
 #[macro_export]
 macro_rules! _decode_and_build {
 	($stream: ident, $thing: path, {$(($type: expr, $field: ident, $fieldty: tt)),* $(,)*}) => { {
+		$crate::_init_and_read_len_prefixed_tlv_fields!($stream, {
+			$(($type, $field, $fieldty)),*
+		});
 		$(
-			$crate::_init_tlv_field_var!($field, $fieldty);
-		)*
-		let tlv_len: $crate::util::ser::BigSize = $crate::util::ser::Readable::read($stream)?;
-		let mut rd = $crate::util::ser::FixedLengthReader::new($stream, tlv_len.0);
-		let rewind = |_, _| { unreachable!() };
-		$crate::_decode_tlv_stream_range!(SKIP_LEGACY, &mut rd, .., rewind, {$(($type, $field, $fieldty)),*});
-		rd.eat_remaining().map_err(|_| $crate::ln::msgs::DecodeError::ShortRead)?;
-		// We mark fields as `mut` as we read them so that legacy post-read actions can modify them
-		// if desired.
-		$(
-			#[allow(unused_mut)]
-			let mut $field = $crate::_init_tlv_based_struct_field!($field, $fieldty);
+			let $field = $crate::_init_tlv_based_struct_field!($field, $fieldty);
 		)*
-		$({
-			$crate::_run_legacy_tlv_read_logic!($field, $fieldty);
-		})*
-
 		::lightning_macros::drop_legacy_field_definition!($thing {
 			$($field: $crate::_ignore_arg!($field, $fieldty)),*
 		})
@@ -973,10 +944,10 @@ macro_rules! _decode_and_build {
 /// If `$fieldty` is `option`, then `$field` is optional field.
 /// If `$fieldty` is `optional_vec`, then `$field` is a [`Vec`], which needs to have its individual elements serialized.
 ///    Note that for `optional_vec` no bytes are written if the vec is empty
-/// If `$fieldty` is `(legacy, $ty, $read, $write)` then, when writing, the expression $write will
+/// If `$fieldty` is `(legacy, $ty, $write)` then, when writing, the expression $write will
 ///    be called which returns an `Option` and is written as a TLV if `Some`. When reading, an
-///    optional field of type `$ty` is read. The code in `$read` is always executed after all TLVs
-///    have been read.
+///    optional field of type `$ty` is read (which can be used in later `default_value` or
+///    `static_value` fields).
 ///
 /// For example,
 /// ```