Simplifies the implementation of common/uuid

This commit is contained in:
Jonas Pfenniger 2013-10-23 23:05:02 +01:00
parent fa0a0a895f
commit 440e966c6e
1 changed files with 11 additions and 19 deletions

View File

@ -1,32 +1,24 @@
package uuid
import (
"fmt"
"crypto/rand"
"encoding/binary"
"fmt"
"time"
)
func uint32rand() (value uint32) {
err := binary.Read(rand.Reader, binary.LittleEndian, &value)
if err != nil {
panic(err)
}
return
}
// Generates a time ordered UUID. Top 32 bits are a timestamp,
// bottom 96 are random.
func TimeOrderedUUID() string {
unix := uint32(time.Now().UTC().Unix())
rand1 := uint32rand()
rand2 := uint32rand()
rand3 := uint32rand()
b := make([]byte, 12)
n, err := rand.Read(b)
if n != len(b) {
err = fmt.Errorf("Not enough entropy available")
}
if err != nil {
panic(err)
}
return fmt.Sprintf("%08x-%04x-%04x-%04x-%04x%08x",
unix,
uint16(rand1>>16),
uint16(rand1&0xffff),
uint16(rand2>>16),
uint16(rand2&0xffff),
rand3)
unix, b[0:2], b[2:4], b[4:6], b[6:8], b[8:])
}