Struct CollectionLength

pub struct CollectionLength(pub u64);

The lightning protocol uses u16s for lengths in most cases. As our serialization framework primarily targets that, we must as well. However, because we may serialize objects that have more than 65K entries, we need to be able to store larger values. Thus, we define a variable length integer here that is backwards-compatible for values < 0xffff. We treat 0xffff as “read eight more bytes”.

To ensure we only have one valid encoding per value, we add 0xffff to values written as eight bytes. Thus, 0xfffe is serialized as 0xfffe, whereas 0xffff is serialized as 0xffff0000000000000000 (i.e. read-eight-bytes then zero).

Tuple Fields

0: u64

Trait Implementations

impl Readable for CollectionLength

fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError>

Reads a Self in from the given Read.

impl Writeable for CollectionLength

fn write<W: Writer>(&self, writer: &mut W) -> Result<(), Error>

Writes self out to the given Writer.

fn encode(&self) -> Vec<u8>

Writes self out to a Vec<u8>.

fn serialized_length(&self) -> usize

Gets the length of this object after it has been serialized. This can be overridden to optimize cases where we prepend an object with its length.