update

locker/empty_locker.go

@@ -1,5 +1,8 @@
 package locker
 
+var _ RWLocker = &emptyLocker{}
+var _ Locker = &emptyLocker{}
+
 var EmptyLocker = &emptyLocker{}
 
 type emptyLocker struct{}

locker/synchronizeable.go

@@ -0,0 +1,96 @@
+package locker
+
+import (
+	"log"
+	"sync"
+)
+
+type WithLocker struct {
+	once sync.Once
+	mu   Locker
+}
+
+func (w *WithLocker) Synchronize() {
+	if w.mu == nil || w.mu == EmptyLocker {
+		w.mu = NewLocker()
+	}
+}
+
+func (w *WithLocker) Lock() {
+	w.ensureLocker().Lock()
+}
+
+func (w *WithLocker) Unlock() {
+	w.ensureLocker().Unlock()
+}
+
+func (w *WithLocker) TryLock() bool {
+	return w.ensureLocker().TryLock()
+}
+
+func (w *WithLocker) ensureLocker() Locker {
+	w.once.Do(func() {
+		if w.mu == nil {
+			w.mu = EmptyLocker
+		}
+	})
+
+	return w.mu
+}
+
+type WithSpinLocker struct {
+	WithLocker
+}
+
+func (w *WithSpinLocker) Synchronize() {
+	if w.mu == nil || w.mu == EmptyLocker {
+		w.mu = NewSpinLocker()
+	}
+}
+
+type WithRWLocker struct {
+	once sync.Once
+	mu   RWLocker
+}
+
+func (w *WithRWLocker) Synchronize() {
+	if w.mu == nil || w.mu == EmptyLocker {
+		log.Println("初始化有效锁")
+		w.mu = NewRWLocker()
+	}
+}
+
+func (w *WithRWLocker) Lock() {
+	w.ensureLocker().Lock()
+}
+
+func (w *WithRWLocker) TryLock() bool {
+	return w.ensureLocker().TryLock()
+}
+
+func (w *WithRWLocker) Unlock() {
+	w.ensureLocker().Unlock()
+}
+
+func (w *WithRWLocker) RLock() {
+	w.ensureLocker().RLock()
+}
+
+func (w *WithRWLocker) TryRLock() bool {
+	return w.ensureLocker().TryRLock()
+}
+
+func (w *WithRWLocker) RUnlock() {
+	w.ensureLocker().RUnlock()
+}
+
+func (w *WithRWLocker) ensureLocker() RWLocker {
+	w.once.Do(func() {
+		if w.mu == nil {
+			log.Println("初始化一个空锁")
+			w.mu = EmptyLocker
+		}
+	})
+
+	return w.mu
+}