Initial QSfera import

Server/vendor/go-micro.dev/v4/server/rpc_util.go

@@ -0,0 +1,39 @@
+package server
+
+import (
+	"sync"
+)
+
+// waitgroup for global management of connections.
+type waitGroup struct {
+	// global waitgroup
+	gg *sync.WaitGroup
+	// local waitgroup
+	lg sync.WaitGroup
+}
+
+// NewWaitGroup returns a new double waitgroup for global management of processes.
+func NewWaitGroup(gWg *sync.WaitGroup) *waitGroup {
+	return &waitGroup{
+		gg: gWg,
+	}
+}
+
+func (w *waitGroup) Add(i int) {
+	w.lg.Add(i)
+	if w.gg != nil {
+		w.gg.Add(i)
+	}
+}
+
+func (w *waitGroup) Done() {
+	w.lg.Done()
+	if w.gg != nil {
+		w.gg.Done()
+	}
+}
+
+func (w *waitGroup) Wait() {
+	// only wait on local group
+	w.lg.Wait()
+}