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