53 lines
1.1 KiB
Go
53 lines
1.1 KiB
Go
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package multibase
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import (
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"fmt"
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"strconv"
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"strings"
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)
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// binaryEncodeToString takes an array of bytes and returns
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// multibase binary representation
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func binaryEncodeToString(src []byte) string {
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dst := make([]byte, len(src)*8)
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encodeBinary(dst, src)
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return string(dst)
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}
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// encodeBinary takes the src and dst bytes and converts each
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// byte to their binary rep using power reduction method
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func encodeBinary(dst []byte, src []byte) {
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for i, b := range src {
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for j := 0; j < 8; j++ {
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if b&(1<<uint(7-j)) == 0 {
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dst[i*8+j] = '0'
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} else {
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dst[i*8+j] = '1'
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}
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}
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}
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}
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// decodeBinaryString takes multibase binary representation
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// and returns a byte array
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func decodeBinaryString(s string) ([]byte, error) {
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if len(s)&7 != 0 {
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// prepend the padding
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s = strings.Repeat("0", 8-len(s)&7) + s
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}
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data := make([]byte, len(s)>>3)
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for i, dstIndex := 0, 0; i < len(s); i = i + 8 {
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value, err := strconv.ParseInt(s[i:i+8], 2, 0)
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if err != nil {
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return nil, fmt.Errorf("error while conversion: %s", err)
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}
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data[dstIndex] = byte(value)
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dstIndex++
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}
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return data, nil
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}
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