Merge pull request #2128 from valentinewallace/2023-03-route-blinding-groundwork

[rust-lightning] / lightning / src / util / ser_macros.rs

diff --git a/lightning/src/util/ser_macros.rs b/lightning/src/util/ser_macros.rs
index 37b8be54ebc2d4db6d53fe0c06582650edecc9f5..1744b923d5e92589eee665c5a1ef1e263b6cfd8b 100644 (file)
--- 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 $value
+//  * required_vec - reads into a Vec without a length prefix, failing if no TLV is present.
+//  * optional_vec - reads into an Option<Vec> without a length prefix, continuing if no TLV is
+//                   present. Writes from a Vec directly, only if any elements are present. Note
+//                   that the struct deserialization macros return a Vec, not an Option.
+//  * upgradable_option - reads via MaybeReadable.
+//  * upgradable_required - reads via MaybeReadable, requiring a TLV be present but may return None
+//                          if MaybeReadable::read() returns None.
+
 /// Implements serialization for a single TLV record.
 /// This is exported for use by other exported macros, do not use directly.
 #[doc(hidden)]
@@ -32,9 +47,6 @@ macro_rules! _encode_tlv {
        ($stream: expr, $type: expr, $field: expr, required_vec) => {
                $crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
        };
-       ($stream: expr, $type: expr, $field: expr, vec_type) => {
-               $crate::_encode_tlv!($stream, $type, $crate::util::ser::WithoutLength(&$field), required);
-       };
        ($stream: expr, $optional_type: expr, $optional_field: expr, option) => {
                if let Some(ref field) = $optional_field {
                        BigSize($optional_type).write($stream)?;
@@ -165,9 +177,6 @@ macro_rules! _get_varint_length_prefixed_tlv_length {
        ($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, $type: expr, $field: expr, vec_type) => {
-               $crate::_get_varint_length_prefixed_tlv_length!($len, $type, $crate::util::ser::WithoutLength(&$field), required);
-       };
        ($len: expr, $optional_type: expr, $optional_field: expr, option) => {
                if let Some(ref field) = $optional_field {
                        BigSize($optional_type).write(&mut $len).expect("No in-memory data may fail to serialize");
@@ -245,9 +254,6 @@ macro_rules! _check_decoded_tlv_order {
        ($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, $field: ident, vec_type) => {{
-               // no-op
-       }};
        ($last_seen_type: expr, $typ: expr, $type: expr, $field: ident, optional_vec) => {{
                // no-op
        }};
@@ -293,9 +299,6 @@ macro_rules! _check_missing_tlv {
        ($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, $field: ident, vec_type) => {{
-               // no-op
-       }};
        ($last_seen_type: expr, $type: expr, $field: ident, option) => {{
                // no-op
        }};
@@ -336,15 +339,12 @@ macro_rules! _decode_tlv {
                let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
                $field = f.0;
        }};
-       ($reader: expr, $field: ident, vec_type) => {{
-               let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
-               $field = Some(f.0);
-       }};
        ($reader: expr, $field: ident, option) => {{
                $field = Some($crate::util::ser::Readable::read(&mut $reader)?);
        }};
        ($reader: expr, $field: ident, optional_vec) => {{
-               $crate::_decode_tlv!($reader, $field, vec_type);
+               let f: $crate::util::ser::WithoutLength<Vec<_>> = $crate::util::ser::Readable::read(&mut $reader)?;
+               $field = Some(f.0);
        }};
        // `upgradable_required` indicates we're reading a required TLV that may have been upgraded
        // without backwards compat. We'll error if the field is missing, and return `Ok(None)` if the
@@ -713,9 +713,6 @@ macro_rules! _init_tlv_based_struct_field {
        ($field: ident, required_vec) => {
                $field
        };
-       ($field: ident, vec_type) => {
-               $field.unwrap()
-       };
        ($field: ident, optional_vec) => {
                $field.unwrap()
        };
@@ -742,9 +739,6 @@ macro_rules! _init_tlv_field_var {
        ($field: ident, required_vec) => {
                let mut $field = Vec::new();
        };
-       ($field: ident, vec_type) => {
-               let mut $field = Some(Vec::new());
-       };
        ($field: ident, option) => {
                let mut $field = None;
        };
@@ -1003,7 +997,7 @@ 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)