From a854355952341a3ed1696e4f6836e761779094a1 Mon Sep 17 00:00:00 2001
From: boyce <boyce.duan@gmail.com>
Date: Tue, 26 Mar 2019 16:11:39 +0800
Subject: [PATCH] queue add RLockRange method.

---
 util/queue/queue.go     | 2 +-
 util/queue/syncqueue.go | 9 +++++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/util/queue/queue.go b/util/queue/queue.go
index 43d7de4..a4d3cf3 100644
--- a/util/queue/queue.go
+++ b/util/queue/queue.go
@@ -78,7 +78,7 @@ func (q *Queue) Get(i int) interface{} {
 		i += q.count
 	}
 	if i < 0 || i >= q.count {
-		panic("queue: Get() called with index out of range")
+		return nil
 	}
 	// bitwise modulus
 	return q.buf[(q.head+i)&(len(q.buf)-1)]
diff --git a/util/queue/syncqueue.go b/util/queue/syncqueue.go
index 987c560..752665c 100644
--- a/util/queue/syncqueue.go
+++ b/util/queue/syncqueue.go
@@ -43,6 +43,15 @@ func (q *SyncQueue) Pop() interface{} {
 	return q.que.Pop()
 }
 
+func (q *SyncQueue) RLockRange(f func(interface{})) {
+	q.mutex.RLock()
+	defer q.mutex.RUnlock()
+
+	for i := 0; i < q.que.Length(); i++ {
+		f(q.Get(i))
+	}
+}
+
 func NewSyncQueue() *SyncQueue {
 	syncQueue := SyncQueue{}
 	syncQueue.que = NewQueue()