Added RdbTree::collExists() just like RdbBuckets

Rdb.cpp

@@ -913,13 +913,7 @@ bool Rdb::dumpCollLoop ( ) {
 
 		// before we create the file, see if tree has anything for this coll
 		if(m_useTree) {
-			ScopedLock sl(m_tree.getLock());
-
-			const char *k = KEYMIN();
-			int32_t nn = m_tree.getNextNode_unlocked(m_dumpCollnum, k);
-			if ( nn < 0 )
-				continue;
-			if (m_tree.getCollnum_unlocked(nn) != m_dumpCollnum )
+			if(!m_tree.collExists(m_dumpCollnum))
 				continue;
 		} else {
 			if(!m_buckets.collExists(m_dumpCollnum))

RdbTree.cpp

@@ -1641,6 +1641,17 @@ int32_t RdbTree::estimateListSize(collnum_t collnum, const char *startKey, const
 }
 
 
+bool RdbTree::collExists(collnum_t coll) const {
+	ScopedLock sl(m_mtx);
+	int32_t nn = getNextNode_unlocked(coll, KEYMIN());
+	if(nn < 0)
+		return false;
+	if(getCollnum_unlocked(nn) != coll)
+		return false;
+	return true;
+}
+
+
 // . returns a number from 0 to m_numUsedNodes-1
 // . represents the ordering of this key in that range
 // . *retKey is the key that has the returned order

RdbTree.h

@@ -124,6 +124,8 @@ public:
 	// estimate the size of the list defined by these keys
 	int32_t estimateListSize(collnum_t collnum, const char *startKey, const char *endKey, char *minKey, char *maxKey) const;
 
+	bool collExists(collnum_t coll) const;
+
 	/// @todo ALC verify saving/writable logic is okay with multithread
 	bool isSaving() const { return m_isSaving; }
 	bool needsSave() const { return m_needsSave; }