v2fly/common/uuid/uuid.go

89 lines
1.8 KiB
Go

package uuid
import (
"bytes"
"crypto/rand"
"encoding/hex"
"github.com/v2fly/v2ray-core/v4/common"
"github.com/v2fly/v2ray-core/v4/common/errors"
)
var byteGroups = []int{8, 4, 4, 4, 12}
type UUID [16]byte
// String returns the string representation of this UUID.
func (u *UUID) String() string {
bytes := u.Bytes()
result := hex.EncodeToString(bytes[0 : byteGroups[0]/2])
start := byteGroups[0] / 2
for i := 1; i < len(byteGroups); i++ {
nBytes := byteGroups[i] / 2
result += "-"
result += hex.EncodeToString(bytes[start : start+nBytes])
start += nBytes
}
return result
}
// Bytes returns the bytes representation of this UUID.
func (u *UUID) Bytes() []byte {
return u[:]
}
// Equals returns true if this UUID equals another UUID by value.
func (u *UUID) Equals(another *UUID) bool {
if u == nil && another == nil {
return true
}
if u == nil || another == nil {
return false
}
return bytes.Equal(u.Bytes(), another.Bytes())
}
// New creates a UUID with random value.
func New() UUID {
var uuid UUID
common.Must2(rand.Read(uuid.Bytes()))
return uuid
}
// ParseBytes converts a UUID in byte form to object.
func ParseBytes(b []byte) (UUID, error) {
var uuid UUID
if len(b) != 16 {
return uuid, errors.New("invalid UUID: ", b)
}
copy(uuid[:], b)
return uuid, nil
}
// ParseString converts a UUID in string form to object.
func ParseString(str string) (UUID, error) {
var uuid UUID
text := []byte(str)
if len(text) < 32 {
return uuid, errors.New("invalid UUID: ", str)
}
b := uuid.Bytes()
for _, byteGroup := range byteGroups {
if text[0] == '-' {
text = text[1:]
}
if _, err := hex.Decode(b[:byteGroup/2], text[:byteGroup]); err != nil {
return uuid, err
}
text = text[byteGroup:]
b = b[byteGroup/2:]
}
return uuid, nil
}