feat: add virtual machine scan command (#2910)

Co-authored-by: knqyf263 <knqyf263@gmail.com>

pkg/semaphore/semaphore.go

@@ -0,0 +1,30 @@
+package semaphore
+
+import "golang.org/x/sync/semaphore"
+
+const defaultSize = 5
+
+type options struct {
+	size int64
+}
+
+type option func(*options)
+
+func WithDefault(n int64) option {
+	return func(opts *options) {
+		opts.size = defaultSize
+	}
+}
+
+func New(slow bool, opts ...option) *semaphore.Weighted {
+	o := &options{size: defaultSize}
+	for _, opt := range opts {
+		opt(o)
+	}
+	if slow {
+		// Process in series
+		return semaphore.NewWeighted(1)
+	}
+	// Process in parallel
+	return semaphore.NewWeighted(o.size)
+}