Line data    Source code

       1             : // Copyright 2023 The LevelDB-Go and Pebble Authors. All rights reserved. Use
       2             : // of this source code is governed by a BSD-style license that can be found in
       3             : // the LICENSE file.
       4             : 
       5             : package objstorageprovider
       6             : 
       7             : import (
       8             :         "bufio"
       9             : 
      10             :         "github.com/cockroachdb/pebble/objstorage"
      11             :         "github.com/cockroachdb/pebble/vfs"
      12             : )
      13             : 
      14             : // NewFileWritable returns a Writable that uses a file as underlying storage.
      15           1 : func NewFileWritable(file vfs.File) objstorage.Writable {
      16           1 :         return newFileBufferedWritable(file)
      17           1 : }
      18             : 
      19             : type fileBufferedWritable struct {
      20             :         file vfs.File
      21             :         bw   *bufio.Writer
      22             : }
      23             : 
      24             : var _ objstorage.Writable = (*fileBufferedWritable)(nil)
      25             : 
      26           1 : func newFileBufferedWritable(file vfs.File) *fileBufferedWritable {
      27           1 :         return &fileBufferedWritable{
      28           1 :                 file: file,
      29           1 :                 bw:   bufio.NewWriter(file),
      30           1 :         }
      31           1 : }
      32             : 
      33             : // Write is part of the objstorage.Writable interface.
      34           1 : func (w *fileBufferedWritable) Write(p []byte) error {
      35           1 :         // Ignoring the length written since bufio.Writer.Write is guaranteed to
      36           1 :         // return an error if the length written is < len(p).
      37           1 :         _, err := w.bw.Write(p)
      38           1 :         return err
      39           1 : }
      40             : 
      41             : // Finish is part of the objstorage.Writable interface.
      42           1 : func (w *fileBufferedWritable) Finish() error {
      43           1 :         err := w.bw.Flush()
      44           1 :         if err == nil {
      45           1 :                 err = w.file.Sync()
      46           1 :         }
      47           1 :         err = firstError(err, w.file.Close())
      48           1 :         w.bw = nil
      49           1 :         w.file = nil
      50           1 :         return err
      51             : }
      52             : 
      53             : // Abort is part of the objstorage.Writable interface.
      54           1 : func (w *fileBufferedWritable) Abort() {
      55           1 :         _ = w.file.Close()
      56           1 :         w.bw = nil
      57           1 :         w.file = nil
      58           1 : }
      59             : 
      60           1 : func firstError(err0, err1 error) error {
      61           1 :         if err0 != nil {
      62           1 :                 return err0
      63           1 :         }
      64           1 :         return err1
      65             : }