github.com/apache/arrow/go/v7@v7.0.1/parquet/compress/snappy.go (about) 1 // Licensed to the Apache Software Foundation (ASF) under one 2 // or more contributor license agreements. See the NOTICE file 3 // distributed with this work for additional information 4 // regarding copyright ownership. The ASF licenses this file 5 // to you under the Apache License, Version 2.0 (the 6 // "License"); you may not use this file except in compliance 7 // with the License. You may obtain a copy of the License at 8 // 9 // http://www.apache.org/licenses/LICENSE-2.0 10 // 11 // Unless required by applicable law or agreed to in writing, software 12 // distributed under the License is distributed on an "AS IS" BASIS, 13 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 // See the License for the specific language governing permissions and 15 // limitations under the License. 16 17 package compress 18 19 import ( 20 "io" 21 "io/ioutil" 22 23 "github.com/golang/snappy" 24 ) 25 26 type snappyCodec struct{} 27 28 func (snappyCodec) Encode(dst, src []byte) []byte { 29 return snappy.Encode(dst, src) 30 } 31 32 func (snappyCodec) EncodeLevel(dst, src []byte, _ int) []byte { 33 return snappy.Encode(dst, src) 34 } 35 36 func (snappyCodec) Decode(dst, src []byte) []byte { 37 dst, err := snappy.Decode(dst, src) 38 if err != nil { 39 panic(err) 40 } 41 return dst 42 } 43 44 func (snappyCodec) NewReader(r io.Reader) io.ReadCloser { 45 return ioutil.NopCloser(snappy.NewReader(r)) 46 } 47 48 func (snappyCodec) CompressBound(len int64) int64 { 49 return int64(snappy.MaxEncodedLen(int(len))) 50 } 51 52 func (snappyCodec) NewWriter(w io.Writer) io.WriteCloser { 53 return snappy.NewBufferedWriter(w) 54 } 55 56 func (s snappyCodec) NewWriterLevel(w io.Writer, _ int) (io.WriteCloser, error) { 57 return s.NewWriter(w), nil 58 } 59 60 func init() { 61 codecs[Codecs.Snappy] = snappyCodec{} 62 }