Revert "src/backup/chunk_stream.rs: simplify code"

This reverts commit e058744d8f.
The optimization was wrong, and produces wrong chunk boundaries.
This commit is contained in:
Dietmar Maurer 2019-05-19 11:05:56 +02:00
parent 178ac042c4
commit ff77dbbea3

View File

@ -9,12 +9,13 @@ pub struct ChunkStream<S: Stream<Item=Vec<u8>, Error=Error>> {
input: S,
chunker: Chunker,
buffer: Option<Vec<u8>>,
rest: Option<Vec<u8>>,
}
impl <S: Stream<Item=Vec<u8>, Error=Error>> ChunkStream<S> {
pub fn new(input: S) -> Self {
Self { input, chunker: Chunker::new(4 * 1024 * 1024), buffer: None }
Self { input, chunker: Chunker::new(4 * 1024 * 1024), buffer: None, rest: None }
}
}
@ -33,9 +34,18 @@ impl <S: Stream<Item=Vec<u8>, Error=Error>> Stream for ChunkStream<S> {
return Ok(Async::NotReady);
}
Ok(Async::Ready(None)) => {
return Ok(Async::Ready(self.buffer.take()));
let mut data = self.buffer.take().or_else(|| Some(vec![])).unwrap();
if let Some(rest) = self.rest.take() { data.extend(rest); }
if data.len() > 0 {
return Ok(Async::Ready(Some(data)));
} else {
return Ok(Async::Ready(None));
}
}
Ok(Async::Ready(Some(data))) => {
Ok(Async::Ready(Some(mut data))) => {
if let Some(rest) = self.rest.take() { data.extend(rest); }
let buffer = self.buffer.get_or_insert_with(|| Vec::with_capacity(1024*1024));
let boundary = self.chunker.scan(&data);
@ -50,11 +60,10 @@ impl <S: Stream<Item=Vec<u8>, Error=Error>> Stream for ChunkStream<S> {
let (left, right) = data.split_at(boundary);
buffer.extend(left);
let result = self.buffer.take();
let rest = self.rest.get_or_insert_with(|| Vec::with_capacity(right.len()));
rest.extend(right);
self.buffer = Some(Vec::from(right));
return Ok(Async::Ready(result));
return Ok(Async::Ready(self.buffer.take()));
} else {
panic!("got unexpected chunk boundary from chunker");
}