2
2
mirror of https://github.com/octoleo/restic.git synced 2024-11-11 15:51:02 +00:00
restic/internal/textfile/read.go
Alexander Neumann eb6650b201 Add textfile
2018-05-01 14:38:59 +02:00

44 lines
1.1 KiB
Go

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