xsync -> xcontext

xcontext/mutex.go

@@ -0,0 +1,37 @@
+package xcontext
+
+type Mutex struct {
+	ch chan struct{}
+}
+
+func NewMutex() *Mutex {
+	return &Mutex{
+		ch: make(chan struct{}, 1),
+	}
+}
+
+func (m *Mutex) TryLock() bool {
+	select {
+	case m.ch <- struct{}{}:
+		return true
+	default:
+		return false
+	}
+}
+
+func (m *Mutex) Lock(ctx context.Context) error {
+	select {
+	case <-ctx.Done():
+		return fmt.Errorf("failed to acquire lock: %w", ctx.Err())
+	case m.ch <- struct{}{}:
+		return nil
+	}
+}
+
+func (m *Mutex) Unlock() {
+	select {
+	case <-m.ch:
+	default:
+		panic("xcontext.Mutex: Unlock before Lock")
+	}
+}