io: WithCompression resuse snappy.Reader and snappy.Writer

utils/pool/snappy.go

@@ -0,0 +1,57 @@
+// Copyright 2017 fatedier, fatedier@gmail.com
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package pool
+
+import (
+	"io"
+	"sync"
+
+	"github.com/golang/snappy"
+)
+
+var (
+	snappyReaderPool sync.Pool
+	snappyWriterPool sync.Pool
+)
+
+func GetSnappyReader(r io.Reader) *snappy.Reader {
+	var x interface{}
+	x = snappyReaderPool.Get()
+	if x == nil {
+		return snappy.NewReader(r)
+	}
+	sr := x.(*snappy.Reader)
+	sr.Reset(r)
+	return sr
+}
+
+func PutSnappyReader(sr *snappy.Reader) {
+	snappyReaderPool.Put(sr)
+}
+
+func GetSnappyWriter(w io.Writer) *snappy.Writer {
+	var x interface{}
+	x = snappyWriterPool.Get()
+	if x == nil {
+		return snappy.NewWriter(w)
+	}
+	sw := x.(*snappy.Writer)
+	sw.Reset(w)
+	return sw
+}
+
+func PutSnappyWriter(sw *snappy.Writer) {
+	snappyWriterPool.Put(sw)
+}