feat: various refactorings

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>

api/backend/lock.go

@@ -0,0 +1,22 @@
+package backend
+
+import "sync"
+
+// mutex still needed, see: https://github.com/ggerganov/llama.cpp/discussions/784
+var mutexMap sync.Mutex
+var mutexes map[string]*sync.Mutex = make(map[string]*sync.Mutex)
+
+func Lock(s string) *sync.Mutex {
+	// This is still needed, see: https://github.com/ggerganov/llama.cpp/discussions/784
+	mutexMap.Lock()
+	l, ok := mutexes[s]
+	if !ok {
+		m := &sync.Mutex{}
+		mutexes[s] = m
+		l = m
+	}
+	mutexMap.Unlock()
+	l.Lock()
+
+	return l
+}