49 lines
665 B
Go
49 lines
665 B
Go
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package fst
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import (
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"crypto/rand"
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"encoding/hex"
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"errors"
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"fmt"
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)
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type ID [16]byte
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var (
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ErrInvalidLength = errors.New("string representation must have a length of 32")
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)
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func (a *ID) String() string {
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return hex.EncodeToString(a[:])
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}
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func NewAppID(id *ID) error {
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_, err := rand.Read(id[:])
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return err
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}
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func ParseAppID(id *ID, s string) error {
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if len(s) != 32 {
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return ErrInvalidLength
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}
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for i, b := range s {
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if b < '0' || b > 'f' {
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return fmt.Errorf("invalid char %q at byte %d", b, i)
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}
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v := uint8(b)
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if v > '9' {
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v = 10 + v - 'a'
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} else {
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v -= '0'
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}
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if i%2 == 0 {
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v <<= 4
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}
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id[i/2] += v
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}
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return nil
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}
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