set up api chain

bpt/include/bpt/bpt.hpp

@@ -34,6 +34,7 @@ class BPlusTreeIndexer {
       // TODO
     }
   };
+  BPlusTreeIndexer() = delete;
   BPlusTreeIndexer(const BPlusTreeIndexer &) = delete;
   BPlusTreeIndexer(BPlusTreeIndexer &&) = delete;
   BPlusTreeIndexer &operator=(const BPlusTreeIndexer &) = delete;
@@ -80,12 +81,17 @@ class BPlusTreeIndexer {
     return true;
   }
   size_t Size() { return siz; }
+  void Flush() {
+    // TODO: do some recording
+    bpm->FlushAllPages();
+  }
 
  private:
-  page_id_t root_page_id;
-  size_t siz;
+  page_id_t root_page_id;  // stored in the first 4 (0-3) bytes of RawDatMemory
+  uint64_t siz;            // stored in the next 8 (4-11) bytes of RawDatMemory
   static KeyComparator key_cmp;
   std::shared_mutex latch;
+  BufferPoolManager *bpm;
 };
 template <typename KeyType, typename KeyComparator>
 KeyComparator BPlusTreeIndexer<KeyType, KeyComparator>::key_cmp = KeyComparator();

bpt/include/bpt/buffer_pool_manager.h

@@ -249,6 +249,8 @@ class BufferPoolManager {
   BufferPoolManager &operator=(const BufferPoolManager &) = delete;
   BufferPoolManager &operator=(BufferPoolManager &&) = delete;
   ~BufferPoolManager();
+  inline char *RawDataMemory() { return disk_manager->RawDataMemory(); }
+  inline size_t RawDatMemorySize() { return disk_manager->RawDatMemorySize(); }
   /**
    * @brief Allocate a page on disk. Caller should acquire the latch before calling this function.
    * @return the id of the allocated page

bpt/include/bpt/disk_manager.h

@@ -21,7 +21,7 @@ class DiskManager {
   ~DiskManager();
   char *RawDataMemory();
   size_t RawDatMemorySize();
-  void FlushInternalPage();
+  void FullyFlush();
   void Close();
   void ReadPage(page_id_t page_id, char *page_data_ptr);
   void WritePage(page_id_t page_id, const char *page_data_ptr);  // in fact, the page_id is the offest