Merge pull request #2015 from TheBlueMatt/2023-02-no-dumb-redundant-fields

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

diff --git a/lightning/src/util/ser.rs b/lightning/src/util/ser.rs
index 847005e324e60f5a0e2e42d67e31009571b27e2b..14c25775174b19dc50f4dabe5ecb434ce0ea259b 100644 (file)
--- a/lightning/src/util/ser.rs
+++ b/lightning/src/util/ser.rs
@@ -289,18 +289,36 @@ impl<T: Readable> MaybeReadable for T {
 }
 
 /// Wrapper to read a required (non-optional) TLV record.
-pub struct OptionDeserWrapper<T: Readable>(pub Option<T>);
-impl<T: Readable> Readable for OptionDeserWrapper<T> {
+pub struct RequiredWrapper<T>(pub Option<T>);
+impl<T: Readable> Readable for RequiredWrapper<T> {
        #[inline]
        fn read<R: Read>(reader: &mut R) -> Result<Self, DecodeError> {
                Ok(Self(Some(Readable::read(reader)?)))
        }
 }
+impl<A, T: ReadableArgs<A>> ReadableArgs<A> for RequiredWrapper<T> {
+       #[inline]
+       fn read<R: Read>(reader: &mut R, args: A) -> Result<Self, DecodeError> {
+               Ok(Self(Some(ReadableArgs::read(reader, args)?)))
+       }
+}
 /// When handling `default_values`, we want to map the default-value T directly
-/// to a `OptionDeserWrapper<T>` in a way that works for `field: T = t;` as
+/// to a `RequiredWrapper<T>` in a way that works for `field: T = t;` as
 /// well. Thus, we assume `Into<T> for T` does nothing and use that.
-impl<T: Readable> From<T> for OptionDeserWrapper<T> {
-       fn from(t: T) -> OptionDeserWrapper<T> { OptionDeserWrapper(Some(t)) }
+impl<T> From<T> for RequiredWrapper<T> {
+       fn from(t: T) -> RequiredWrapper<T> { RequiredWrapper(Some(t)) }
+}
+
+/// Wrapper to read a required (non-optional) TLV record that may have been upgraded without
+/// backwards compat.
+pub struct UpgradableRequired<T: MaybeReadable>(pub Option<T>);
+impl<T: MaybeReadable> MaybeReadable for UpgradableRequired<T> {
+       #[inline]
+       fn read<R: Read>(reader: &mut R) -> Result<Option<Self>, DecodeError> {
+               let tlv = MaybeReadable::read(reader)?;
+               if let Some(tlv) = tlv { return Ok(Some(Self(Some(tlv)))) }
+               Ok(None)
+       }
 }
 
 pub(crate) struct U48(pub u64);