storage: Making use of SkipList-based index

Change-Id: I360af97ae794da383fe00aaad8ab3c417c5167d3
Refs: #1695, #1434
diff --git a/src/storage/storage.hpp b/src/storage/storage.hpp
new file mode 100755
index 0000000..04f366f
--- /dev/null
+++ b/src/storage/storage.hpp
@@ -0,0 +1,99 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014,  Regents of the University of California.
+ *
+ * This file is part of NDN repo-ng (Next generation of NDN repository).
+ * See AUTHORS.md for complete list of repo-ng authors and contributors.
+ *
+ * repo-ng is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * repo-ng is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * repo-ng, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef REPO_STORAGE_STORAGE_HPP
+#define REPO_STORAGE_STORAGE_HPP
+#include <string>
+#include <iostream>
+#include <stdlib.h>
+#include "../common.hpp"
+
+namespace repo {
+
+/**
+  * @brief Storage is a virtual abstract class which will be called by SqliteStorage
+  */
+class Storage : noncopyable
+{
+public:
+  class Error : public std::runtime_error
+  {
+  public:
+    explicit
+    Error(const std::string& what)
+      : std::runtime_error(what)
+    {
+    }
+  };
+
+public:
+  class ItemMeta
+  {
+  public:
+    int64_t id;
+    Name fullName;
+    ndn::ConstBufferPtr keyLocatorHash;
+  };
+
+public :
+
+  virtual
+  ~Storage()
+  {
+  };
+
+  /**
+   *  @brief  put the data into database
+   *  @param  data   the data should be inserted into databse
+   */
+  virtual int64_t
+  insert(const Data& data) = 0;
+
+  /**
+   *  @brief  remove the entry in the database by using id
+   *  @param  id   id number of entry in the database
+   */
+  virtual bool
+  erase(const int64_t id) = 0;
+
+  /**
+   *  @brief  get the data from database
+   *  @param  id   id number of each entry in the database, used to find the data
+   */
+  virtual shared_ptr<Data>
+  read(const int64_t id) = 0;
+
+  /**
+   *  @brief  return the size of database
+   */
+  virtual int64_t
+  size() = 0;
+
+  /**
+   *  @brief enumerate each entry in database and call the function
+   *         insertItemToIndex to reubuild index from database
+   */
+  virtual void
+  fullEnumerate(const ndn::function<void(const Storage::ItemMeta)>& f) = 0;
+
+};
+
+} // namespace repo
+
+#endif // REPO_STORAGE_Storage_HPP