github.com/mier85/go-sensor@v1.30.1-0.20220920111756-9bf41b3bc7e0/autoprofile/internal/uuid.go (about)

     1  // (c) Copyright IBM Corp. 2021
     2  // (c) Copyright Instana Inc. 2020
     3  
     4  package internal
     5  
     6  import (
     7  	"crypto/sha1"
     8  	"encoding/hex"
     9  	"math/rand"
    10  	"strconv"
    11  	"sync"
    12  	"sync/atomic"
    13  	"time"
    14  )
    15  
    16  var (
    17  	randSource = rand.New(rand.NewSource(time.Now().UnixNano()))
    18  	randLock   sync.Mutex
    19  	nextID     int64
    20  )
    21  
    22  // GenerateUUID generates a new UUID string
    23  func GenerateUUID() string {
    24  	n := atomic.AddInt64(&nextID, 1)
    25  
    26  	uuid := strconv.FormatInt(time.Now().Unix(), 10) +
    27  		strconv.FormatInt(random(1000000000), 10) +
    28  		strconv.FormatInt(n, 10)
    29  
    30  	return sha1String(uuid)
    31  }
    32  
    33  func random(max int64) int64 {
    34  	randLock.Lock()
    35  	defer randLock.Unlock()
    36  
    37  	return randSource.Int63n(max)
    38  }
    39  
    40  func sha1String(s string) string {
    41  	sha1 := sha1.New()
    42  	sha1.Write([]byte(s))
    43  
    44  	return hex.EncodeToString(sha1.Sum(nil))
    45  }