github.com/cockroachdb/cockroach@v20.2.0-alpha.1+incompatible/pkg/storage/file_util.go (about)

     1  // Copyright 2019 The Cockroach Authors.
     2  //
     3  // Use of this software is governed by the Business Source License
     4  // included in the file licenses/BSL.txt.
     5  //
     6  // As of the Change Date specified in that file, in accordance with
     7  // the Business Source License, use of this software will be governed
     8  // by the Apache License, Version 2.0, included in the file
     9  // licenses/APL.txt.
    10  
    11  package storage
    12  
    13  import (
    14  	"bytes"
    15  	"fmt"
    16  	"io"
    17  
    18  	"github.com/cockroachdb/pebble/vfs"
    19  )
    20  
    21  // SafeWriteToFile writes the byte slice to the filename, contained in dir, using the given fs.
    22  // It returns after both the file and the containing directory are synced.
    23  func SafeWriteToFile(fs vfs.FS, dir string, filename string, b []byte) error {
    24  	tempName := filename + ".crdbtmp"
    25  	f, err := fs.Create(tempName)
    26  	if err != nil {
    27  		fmt.Printf("%v\n", err)
    28  		return err
    29  	}
    30  	bReader := bytes.NewReader(b)
    31  	if _, err = io.Copy(f, bReader); err != nil {
    32  		f.Close()
    33  		return err
    34  	}
    35  	if err = f.Close(); err != nil {
    36  		return err
    37  	}
    38  	if err = fs.Rename(tempName, filename); err != nil {
    39  		return err
    40  	}
    41  	fdir, err := fs.OpenDir(dir)
    42  	if err != nil {
    43  		return err
    44  	}
    45  	defer fdir.Close()
    46  	return fdir.Sync()
    47  }