Opentracing support

vendor/github.com/openzipkin/zipkin-go-opentracing/util.go

@@ -0,0 +1,25 @@
+package zipkintracer
+
+import (
+	"math/rand"
+	"sync"
+	"time"
+)
+
+var (
+	seededIDGen = rand.New(rand.NewSource(time.Now().UnixNano()))
+	// The golang rand generators are *not* intrinsically thread-safe.
+	seededIDLock sync.Mutex
+)
+
+func randomID() uint64 {
+	seededIDLock.Lock()
+	defer seededIDLock.Unlock()
+	return uint64(seededIDGen.Int63())
+}
+
+func randomID2() (uint64, uint64) {
+	seededIDLock.Lock()
+	defer seededIDLock.Unlock()
+	return uint64(seededIDGen.Int63()), uint64(seededIDGen.Int63())
+}