X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Futil%2Fser.rs;h=7ff6b248cfb423feabf6d5277a0178aceaef82d7;hb=4ad00f4074bfaf3ae5e6aa816aaa488d473624ed;hp=0611e6ffb385b66459f93d3cee1fc46ec1f46223;hpb=9ca22800b4eefde53776e8fbbc2e187e07f393da;p=rust-lightning

diff --git a/lightning/src/util/ser.rs b/lightning/src/util/ser.rs
index 0611e6ff..7ff6b248 100644
--- a/lightning/src/util/ser.rs
+++ b/lightning/src/util/ser.rs
@@ -108,14 +108,14 @@ impl Writer for LengthCalculatingWriter {
 /// forward to ensure we always consume exactly the fixed length specified.
 ///
 /// This is not exported to bindings users as manual TLV building is not currently supported in bindings
-pub struct FixedLengthReader<R: Read> {
-	read: R,
+pub struct FixedLengthReader<'a, R: Read> {
+	read: &'a mut R,
 	bytes_read: u64,
 	total_bytes: u64,
 }
-impl<R: Read> FixedLengthReader<R> {
+impl<'a, R: Read> FixedLengthReader<'a, R> {
 	/// Returns a new [`FixedLengthReader`].
-	pub fn new(read: R, total_bytes: u64) -> Self {
+	pub fn new(read: &'a mut R, total_bytes: u64) -> Self {
 		Self { read, bytes_read: 0, total_bytes }
 	}
 
@@ -136,7 +136,7 @@ impl<R: Read> FixedLengthReader<R> {
 		}
 	}
 }
-impl<R: Read> Read for FixedLengthReader<R> {
+impl<'a, R: Read> Read for FixedLengthReader<'a, R> {
 	#[inline]
 	fn read(&mut self, dest: &mut [u8]) -> Result<usize, io::Error> {
 		if self.total_bytes == self.bytes_read {
@@ -154,7 +154,7 @@ impl<R: Read> Read for FixedLengthReader<R> {
 	}
 }
 
-impl<R: Read> LengthRead for FixedLengthReader<R> {
+impl<'a, R: Read> LengthRead for FixedLengthReader<'a, R> {
 	#[inline]
 	fn total_bytes(&self) -> u64 {
 		self.total_bytes
@@ -820,6 +820,49 @@ macro_rules! impl_for_vec {
 	}
 }
 
+// Alternatives to impl_writeable_for_vec/impl_readable_for_vec that add a length prefix to each
+// element in the Vec. Intended to be used when elements have variable lengths.
+macro_rules! impl_writeable_for_vec_with_element_length_prefix {
+	($ty: ty $(, $name: ident)*) => {
+		impl<$($name : Writeable),*> Writeable for Vec<$ty> {
+			#[inline]
+			fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+				CollectionLength(self.len() as u64).write(w)?;
+				for elem in self.iter() {
+					CollectionLength(elem.serialized_length() as u64).write(w)?;
+					elem.write(w)?;
+				}
+				Ok(())
+			}
+		}
+	}
+}
+macro_rules! impl_readable_for_vec_with_element_length_prefix {
+	($ty: ty $(, $name: ident)*) => {
+		impl<$($name : Readable),*> Readable for Vec<$ty> {
+			#[inline]
+			fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+				let len: CollectionLength = Readable::read(r)?;
+				let mut ret = Vec::with_capacity(cmp::min(len.0 as usize, MAX_BUF_SIZE / core::mem::size_of::<$ty>()));
+				for _ in 0..len.0 {
+					let elem_len: CollectionLength = Readable::read(r)?;
+					let mut elem_reader = FixedLengthReader::new(r, elem_len.0);
+					if let Some(val) = MaybeReadable::read(&mut elem_reader)? {
+						ret.push(val);
+					}
+				}
+				Ok(ret)
+			}
+		}
+	}
+}
+macro_rules! impl_for_vec_with_element_length_prefix {
+	($ty: ty $(, $name: ident)*) => {
+		impl_writeable_for_vec_with_element_length_prefix!($ty $(, $name)*);
+		impl_readable_for_vec_with_element_length_prefix!($ty $(, $name)*);
+	}
+}
+
 impl Writeable for Vec<u8> {
 	#[inline]
 	fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
@@ -851,6 +894,8 @@ impl_for_vec!(crate::ln::msgs::SocketAddress);
 impl_for_vec!((A, B), A, B);
 impl_writeable_for_vec!(&crate::routing::router::BlindedTail);
 impl_readable_for_vec!(crate::routing::router::BlindedTail);
+impl_for_vec_with_element_length_prefix!(crate::ln::msgs::UpdateAddHTLC);
+impl_writeable_for_vec_with_element_length_prefix!(&crate::ln::msgs::UpdateAddHTLC);
 
 impl Writeable for Vec<Witness> {
 	#[inline]