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use crate::error::EncodeError;
pub trait Writer {
fn write(&mut self, bytes: &[u8]) -> Result<(), EncodeError>;
}
impl<T: Writer> Writer for &mut T {
#[inline]
fn write(&mut self, bytes: &[u8]) -> Result<(), EncodeError> {
(**self).write(bytes)
}
}
pub struct SliceWriter<'storage> {
slice: &'storage mut [u8],
original_length: usize,
}
impl<'storage> SliceWriter<'storage> {
pub fn new(bytes: &'storage mut [u8]) -> SliceWriter<'storage> {
let original = bytes.len();
SliceWriter {
slice: bytes,
original_length: original,
}
}
pub fn bytes_written(&self) -> usize {
self.original_length - self.slice.len()
}
}
impl<'storage> Writer for SliceWriter<'storage> {
#[inline(always)]
fn write(&mut self, bytes: &[u8]) -> Result<(), EncodeError> {
if bytes.len() > self.slice.len() {
return Err(EncodeError::UnexpectedEnd);
}
let (a, b) = core::mem::take(&mut self.slice).split_at_mut(bytes.len());
a.copy_from_slice(bytes);
self.slice = b;
Ok(())
}
}