ceremonyclient/pebble/sstable/compression_nocgo.go
Cassandra Heart 2e2a1e4789
v1.2.0 (#31)
2024-01-03 01:31:42 -06:00

31 lines
1.2 KiB
Go

// Copyright 2021 The LevelDB-Go and Pebble Authors. All rights reserved. Use
// of this source code is governed by a BSD-style license that can be found in
// the LICENSE file.
//go:build !cgo
// +build !cgo
package sstable
import "github.com/klauspost/compress/zstd"
// decodeZstd decompresses b with the Zstandard algorithm.
// It reuses the preallocated capacity of decodedBuf if it is sufficient.
// On success, it returns the decoded byte slice.
func decodeZstd(decodedBuf, b []byte) ([]byte, error) {
decoder, _ := zstd.NewReader(nil)
defer decoder.Close()
return decoder.DecodeAll(b, decodedBuf[:0])
}
// encodeZstd compresses b with the Zstandard algorithm at default compression
// level (level 3). It reuses the preallocated capacity of compressedBuf if it
// is sufficient. The subslice `compressedBuf[:varIntLen]` should already encode
// the length of `b` before calling encodeZstd. It returns the encoded byte
// slice, including the `compressedBuf[:varIntLen]` prefix.
func encodeZstd(compressedBuf []byte, varIntLen int, b []byte) []byte {
encoder, _ := zstd.NewWriter(nil)
defer encoder.Close()
return encoder.EncodeAll(b, compressedBuf[:varIntLen])
}