From e058744d8f4dc1d87fe2a28cd79bc385e934f563 Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Sat, 18 May 2019 10:54:05 +0200
Subject: [PATCH] src/backup/chunk_stream.rs: simplify code

---
 src/backup/chunk_stream.rs | 23 +++++++----------------
 1 file changed, 7 insertions(+), 16 deletions(-)

diff --git a/src/backup/chunk_stream.rs b/src/backup/chunk_stream.rs
index e21224dc..eac9dca1 100644
--- a/src/backup/chunk_stream.rs
+++ b/src/backup/chunk_stream.rs
@@ -9,13 +9,12 @@ 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, rest: None }
+        Self { input, chunker: Chunker::new(4 * 1024 * 1024), buffer: None }
     }
 }
 
@@ -34,18 +33,9 @@ impl <S: Stream<Item=Vec<u8>, Error=Error>> Stream for ChunkStream<S> {
                     return Ok(Async::NotReady);
                 }
                 Ok(Async::Ready(None)) => {
-                    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));
-                    }
+                    return Ok(Async::Ready(self.buffer.take()));
                 }
-                Ok(Async::Ready(Some(mut data))) => {
-
-                    if let Some(rest) = self.rest.take() { data.extend(rest); }
+                Ok(Async::Ready(Some(data))) => {
 
                     let buffer = self.buffer.get_or_insert_with(|| Vec::with_capacity(1024*1024));
                     let boundary = self.chunker.scan(&data);
@@ -60,10 +50,11 @@ impl <S: Stream<Item=Vec<u8>, Error=Error>> Stream for ChunkStream<S> {
                         let (left, right) = data.split_at(boundary);
                         buffer.extend(left);
 
-                        let rest = self.rest.get_or_insert_with(|| Vec::with_capacity(right.len()));
-                        rest.extend(right);
+                        let result = self.buffer.take();
 
-                        return Ok(Async::Ready(self.buffer.take()));
+                        self.buffer = Some(Vec::from(right));
+
+                        return Ok(Async::Ready(result));
                     } else {
                         panic!("got unexpected chunk boundary from chunker");
                     }