[IOTDB-1282] fix C++ class SessionDataSet mem-leak

client-cpp/src/main/Session.h

@@ -523,7 +523,7 @@ private:
     std::vector<std::unique_ptr<MyStringBuffer>> valueBuffers;
     std::vector<std::unique_ptr<MyStringBuffer>> bitmapBuffers;
     RowRecord rowRecord;
-    char* currentBitmap; // used to cache the current bitmap for every column
+    char* currentBitmap = NULL; // used to cache the current bitmap for every column
     static const int flag = 0x80; // used to do `or` operation with bitmap to judge whether the value is null
     
 public:
@@ -554,6 +554,13 @@ public:
         this->tsQueryDataSet = queryDataSet;
     }
 
+    ~SessionDataSet() {
+        if (currentBitmap != NULL) {
+            delete[] currentBitmap;
+            currentBitmap = NULL;
+        }
+    }
+
     int getBatchSize();
     void setBatchSize(int batchSize);
     std::vector<std::string> getColumnNames();