forked from mirror/go.uuid
44 lines
786 B
Go
44 lines
786 B
Go
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package uuid
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import (
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"fmt"
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"crypto/rand"
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)
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type UUID [16]byte
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// Returns algorithm version used to generate UUID
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// RFC 4122 describes version 1, 3, 4 and 5.
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func (u *UUID) Version() uint {
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return uint(u[6] >> 4)
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}
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// Returns canonical string representation of UUID:
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// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
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func (u *UUID) String() string {
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return fmt.Sprintf("%x-%x-%x-%x-%x",
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u[:4], u[4:6], u[6:8], u[8:10], u[10:])
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}
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// Set version bits.
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func (u *UUID) setVersion(v uint) {
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u[6] = (u[6] & 0x0f) | (byte(v) << 4)
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}
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// Set variant bits.
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func (u *UUID) setVariant() {
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u[8] = (u[8] & 0x3f) | 0x80
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}
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// Returns random UUID.
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func NewV4() (u *UUID, err error) {
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u = new(UUID)
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_, err = rand.Read(u[:])
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if err != nil {
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return
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}
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u.setVersion(4)
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u.setVariant()
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return
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}
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