29 lines
849 B
Go
29 lines
849 B
Go
// Copyright 2019 Tailscale & AUTHORS. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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// Package atomicfile contains code related to writing to filesystems
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// atomically.
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//
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// This package should be considered internal; its API is not stable.
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package atomicfile // import "tailscale.com/atomicfile"
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import (
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"fmt"
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"io/ioutil"
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"os"
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)
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// WriteFile writes data to filename+some suffix, then renames it
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// into filename.
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func WriteFile(filename string, data []byte, perm os.FileMode) error {
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tmpname := filename + ".new.tmp"
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if err := ioutil.WriteFile(tmpname, data, perm); err != nil {
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return fmt.Errorf("%#v: %v", tmpname, err)
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}
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if err := os.Rename(tmpname, filename); err != nil {
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return fmt.Errorf("%#v->%#v: %v", tmpname, filename, err)
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}
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return nil
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}
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