core/sql/executor/BufferList.h

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// BufferList.h
//
// BufferList is a buffer list that combines buffer management with a
// Queue.  BufferList does not own the buffers in its list.
//

#ifndef BUFFERLIST_H
#define BUFFERLIST_H

#include <NABasicObject.h>
#include <NAType.h>
#include <ComQueue.h>

#include "ExOverflow.h"

namespace ExOverflow
{

  class BufferList : public NABasicObject
  {
    public:
      BufferList(NAMemory* heap);
      ~BufferList(void);

      // Return a pointer to the last buffer in the list
      char* back(void);

      // Return a pointer to the current buffer in the list
      char* current(void);

      // Is the buffer list empty?
      bool empty(void);

      // Return a pointer to the first buffer in the list
      char* front(void);

      // Return a pointer to the next buffer in the list
      char* next(void);

      // Unlink the first buffer from the list
      char* pop(void);

      // Reset current position to head of list
      void position(void);

      // Insert a buffer at the end of the list
      void push_back(char* buffer);

      // Number of buffers in the buffer list
      UInt32 size(void);

    private:
      Queue bufferList_;        // List of buffers
  };

}

#endif