55 lines
1.2 KiB
Go
55 lines
1.2 KiB
Go
// Copyright (c) HashiCorp, Inc.
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// SPDX-License-Identifier: MPL-2.0
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package file
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import (
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"fmt"
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"os"
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"path/filepath"
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"github.com/hashicorp/go-uuid"
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)
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// WriteAtomic writes the given contents to a temporary file in the same
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// directory, does an fsync and then renames the file to its real path
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func WriteAtomic(path string, contents []byte) error {
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return WriteAtomicWithPerms(path, contents, 0700, 0600)
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}
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func WriteAtomicWithPerms(path string, contents []byte, dirPerms, filePerms os.FileMode) error {
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uuid, err := uuid.GenerateUUID()
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if err != nil {
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return err
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}
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tempPath := fmt.Sprintf("%s-%s.tmp", path, uuid)
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if err := os.MkdirAll(filepath.Dir(path), dirPerms); err != nil {
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return err
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}
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fh, err := os.OpenFile(tempPath, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, filePerms)
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if err != nil {
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return err
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}
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if _, err := fh.Write(contents); err != nil {
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fh.Close()
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os.Remove(tempPath)
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return err
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}
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if err := fh.Sync(); err != nil {
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fh.Close()
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os.Remove(tempPath)
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return err
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}
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if err := fh.Close(); err != nil {
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os.Remove(tempPath)
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return err
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}
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if err := os.Rename(tempPath, path); err != nil {
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os.Remove(tempPath)
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return err
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}
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return nil
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}
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