/// serialization buffer size
pub const MAX_BUF_SIZE: usize = 64 * 1024;
-/// A trait that is similar to std::io::Write but has one extra function which can be used to size
-/// buffers being written into.
-/// An impl is provided for any type that also impls std::io::Write which simply ignores size
-/// hints.
+/// A simplified version of std::io::Write that exists largely for backwards compatibility.
+/// An impl is provided for any type that also impls std::io::Write.
///
/// (C-not exported) as we only export serialization to/from byte arrays instead
pub trait Writer {
/// Writes the given buf out. See std::io::Write::write_all for more
fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error>;
- /// Hints that data of the given size is about the be written. This may not always be called
- /// prior to data being written and may be safely ignored.
- fn size_hint(&mut self, size: usize);
}
impl<W: Write> Writer for W {
fn write_all(&mut self, buf: &[u8]) -> Result<(), io::Error> {
<Self as io::Write>::write_all(self, buf)
}
- #[inline]
- fn size_hint(&mut self, _size: usize) { }
}
pub(crate) struct WriterWriteAdaptor<'a, W: Writer + 'a>(pub &'a mut W);
self.0.extend_from_slice(buf);
Ok(())
}
- #[inline]
- fn size_hint(&mut self, size: usize) {
- self.0.reserve_exact(size);
- }
}
/// Writer that only tracks the amount of data written - useful if you need to calculate the length
self.0 += buf.len();
Ok(())
}
- #[inline]
- fn size_hint(&mut self, _size: usize) {}
}
/// Essentially std::io::Take but a bit simpler and with a method to walk the underlying stream
}
}
+impl Writeable for () {
+ fn write<W: Writer>(&self, _: &mut W) -> Result<(), io::Error> {
+ Ok(())
+ }
+}
impl Readable for () {
fn read<R: Read>(_r: &mut R) -> Result<Self, DecodeError> {
Ok(())
}
}
+
+impl Writeable for String {
+ #[inline]
+ fn write<W: Writer>(&self, w: &mut W) -> Result<(), io::Error> {
+ (self.len() as u16).write(w)?;
+ w.write_all(self.as_bytes())
+ }
+}
+impl Readable for String {
+ #[inline]
+ fn read<R: Read>(r: &mut R) -> Result<Self, DecodeError> {
+ let v: Vec<u8> = Readable::read(r)?;
+ let ret = String::from_utf8(v).map_err(|_| DecodeError::InvalidValue)?;
+ Ok(ret)
+ }
+}