forked from TrueCloudLab/restic
44 lines
1.1 KiB
Go
44 lines
1.1 KiB
Go
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// Package textfile allows reading files that contain text. It automatically
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// detects and converts several encodings and removes Byte Order Marks (BOM).
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package textfile
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import (
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"bytes"
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"io/ioutil"
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"golang.org/x/text/encoding/unicode"
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)
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// All supported BOMs (Byte Order Marks)
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var (
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bomUTF8 = []byte{0xef, 0xbb, 0xbf}
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bomUTF16BigEndian = []byte{0xfe, 0xff}
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bomUTF16LittleEndian = []byte{0xff, 0xfe}
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)
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// Decode removes a byte order mark and converts the bytes to UTF-8.
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func Decode(data []byte) ([]byte, error) {
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if bytes.HasPrefix(data, bomUTF8) {
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return data[len(bomUTF8):], nil
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}
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if !bytes.HasPrefix(data, bomUTF16BigEndian) && !bytes.HasPrefix(data, bomUTF16LittleEndian) {
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// no encoding specified, let's assume UTF-8
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return data, nil
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}
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// UseBom means automatic endianness selection
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e := unicode.UTF16(unicode.BigEndian, unicode.UseBOM)
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return e.NewDecoder().Bytes(data)
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}
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// Read returns the contents of the file, converted to UTF-8, stripped of any BOM.
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func Read(filename string) ([]byte, error) {
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data, err := ioutil.ReadFile(filename)
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if err != nil {
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return nil, err
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}
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return Decode(data)
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}
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