Take advantage of NLL to be able to state-transition & return directly in chunker

This commit is contained in:
Tangent Wantwight 2019-11-16 15:19:14 -05:00
parent 7485119028
commit d3b147f8ea

View file

@ -138,9 +138,6 @@ impl<I: Buf, S: Stream<Item = Result<I, WebmetroError>> + Unpin> Stream for Webm
fn poll_next(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Result<Chunk, WebmetroError>>> {
let mut chunker = self.get_mut();
loop {
let mut return_value = None;
let mut new_state = None;
match chunker.state {
ChunkerState::BuildingHeader(ref mut buffer) => {
match chunker.source.poll_event(cx) {
@ -151,20 +148,20 @@ impl<I: Buf, S: Stream<Item = Result<I, WebmetroError>> + Unpin> Stream for Webm
let liberated_buffer = mem::replace(buffer, Cursor::new(Vec::new()));
let header_chunk = Chunk::Headers {bytes: Bytes::from(liberated_buffer.into_inner())};
return_value = Some(Ok(Async::Ready(Some(header_chunk))));
new_state = Some(ChunkerState::BuildingCluster(
chunker.state = ChunkerState::BuildingCluster(
ClusterHead::new(0),
Cursor::new(Vec::new())
));
);
return Ready(Some(Ok(header_chunk)));
},
Ok(Async::Ready(Some(WebmElement::Info))) => {},
Ok(Async::Ready(Some(WebmElement::Void))) => {},
Ok(Async::Ready(Some(WebmElement::Unknown(_)))) => {},
Ok(Async::Ready(Some(element))) => {
encode(element, buffer, chunker.buffer_size_limit).unwrap_or_else(|err| {
return_value = Some(Err(err));
new_state = Some(ChunkerState::End);
});
if let Err(err) = encode(element, buffer, chunker.buffer_size_limit) {
chunker.state = ChunkerState::End;
return Ready(Some(Err(err)));
}
}
}
},
@ -180,15 +177,15 @@ impl<I: Buf, S: Stream<Item = Result<I, WebmetroError>> + Unpin> Stream for Webm
let mut new_header_cursor = Cursor::new(Vec::new());
match encode(element, &mut new_header_cursor, chunker.buffer_size_limit) {
Ok(_) => {
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterHead(liberated_cluster_head)))));
new_state = Some(ChunkerState::EmittingClusterBodyBeforeNewHeader{
chunker.state = ChunkerState::EmittingClusterBodyBeforeNewHeader{
body: liberated_buffer.into_inner(),
new_header: new_header_cursor
});
};
return Ready(Some(Ok(Chunk::ClusterHead(liberated_cluster_head))));
},
Err(err) => {
return_value = Some(Err(err));
new_state = Some(ChunkerState::End);
chunker.state = ChunkerState::End;
return Ready(Some(Err(err)));
}
}
}
@ -196,8 +193,8 @@ impl<I: Buf, S: Stream<Item = Result<I, WebmetroError>> + Unpin> Stream for Webm
let liberated_cluster_head = mem::replace(cluster_head, ClusterHead::new(0));
let liberated_buffer = mem::replace(buffer, Cursor::new(Vec::new()));
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterHead(liberated_cluster_head)))));
new_state = Some(ChunkerState::EmittingClusterBody(liberated_buffer.into_inner()));
chunker.state = ChunkerState::EmittingClusterBody(liberated_buffer.into_inner());
return Ready(Some(Ok(Chunk::ClusterHead(liberated_cluster_head))));
},
Ok(Async::Ready(Some(WebmElement::Timecode(timecode)))) => {
cluster_head.update_timecode(timecode);
@ -208,67 +205,55 @@ impl<I: Buf, S: Stream<Item = Result<I, WebmetroError>> + Unpin> Stream for Webm
cluster_head.keyframe = true;
}
cluster_head.observe_simpleblock_timecode(block.timecode);
encode(WebmElement::SimpleBlock(*block), buffer, chunker.buffer_size_limit).unwrap_or_else(|err| {
return_value = Some(Err(err));
new_state = Some(ChunkerState::End);
});
if let Err(err) = encode(WebmElement::SimpleBlock(*block), buffer, chunker.buffer_size_limit) {
chunker.state = ChunkerState::End;
return Ready(Some(Err(err)));
}
},
Ok(Async::Ready(Some(WebmElement::Info))) => {},
Ok(Async::Ready(Some(WebmElement::Void))) => {},
Ok(Async::Ready(Some(WebmElement::Unknown(_)))) => {},
Ok(Async::Ready(Some(element))) => {
encode(element, buffer, chunker.buffer_size_limit).unwrap_or_else(|err| {
return_value = Some(Err(err));
new_state = Some(ChunkerState::End);
});
if let Err(err) = encode(element, buffer, chunker.buffer_size_limit) {
chunker.state = ChunkerState::End;
return Ready(Some(Err(err)));
}
},
Ok(Async::Ready(None)) => {
// flush final Cluster on end of stream
let liberated_cluster_head = mem::replace(cluster_head, ClusterHead::new(0));
let liberated_buffer = mem::replace(buffer, Cursor::new(Vec::new()));
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterHead(liberated_cluster_head)))));
new_state = Some(ChunkerState::EmittingFinalClusterBody(liberated_buffer.into_inner()));
chunker.state = ChunkerState::EmittingFinalClusterBody(liberated_buffer.into_inner());
return Ready(Some(Ok(Chunk::ClusterHead(liberated_cluster_head))));
}
}
},
ChunkerState::EmittingClusterBody(ref mut buffer) => {
let liberated_buffer = mem::replace(buffer, Vec::new());
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterBody {bytes: Bytes::from(liberated_buffer)}))));
new_state = Some(ChunkerState::BuildingCluster(
chunker.state = ChunkerState::BuildingCluster(
ClusterHead::new(0),
Cursor::new(Vec::new())
));
);
return Ready(Some(Ok(Chunk::ClusterBody {bytes: Bytes::from(liberated_buffer)})));
},
ChunkerState::EmittingClusterBodyBeforeNewHeader { ref mut body, ref mut new_header } => {
let liberated_body = mem::replace(body, Vec::new());
let liberated_header_cursor = mem::replace(new_header, Cursor::new(Vec::new()));
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterBody {bytes: Bytes::from(liberated_body)}))));
new_state = Some(ChunkerState::BuildingHeader(liberated_header_cursor));
chunker.state = ChunkerState::BuildingHeader(liberated_header_cursor);
return Ready(Some(Ok(Chunk::ClusterBody {bytes: Bytes::from(liberated_body)})));
},
ChunkerState::EmittingFinalClusterBody(ref mut buffer) => {
// flush final Cluster on end of stream
let liberated_buffer = mem::replace(buffer, Vec::new());
return_value = Some(Ok(Async::Ready(Some(Chunk::ClusterBody {bytes: Bytes::from(liberated_buffer)}))));
new_state = Some(ChunkerState::End);
chunker.state = ChunkerState::End;
return Ready(Some(Ok(Chunk::ClusterBody {bytes: Bytes::from(liberated_buffer)})));
},
ChunkerState::End => return Ready(None)
};
if let Some(new_state) = new_state {
chunker.state = new_state;
}
if let Some(return_value) = return_value {
return match return_value {
Ok(Async::Ready(Some(chunk))) => Ready(Some(Ok(chunk))),
Ok(Async::Ready(None)) => Ready(None),
Ok(Async::NotReady) => Pending,
Err(err) => Ready(Some(Err(err))),
};
}
}
}
}