~drizzle-trunk/drizzle/development

/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright (C) 2009 Sun Microsystems, Inc.

 *

 *  This program 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 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program 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 this program; if not, write to the Free Software

 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

#pragma once

#include <drizzled/cursor.h>

#include <plugin/function_engine/function.h>

#include <drizzled/base.h>

class FunctionCursor: public drizzled::Cursor

{

  drizzled::plugin::TableFunction *tool;

  drizzled::plugin::TableFunction::Generator *generator;

  size_t row_cache_position;

  std::vector<unsigned char> row_cache;

  drizzled::ha_rows estimate_of_rows;

  drizzled::ha_rows rows_returned;

  void wipeCache();

  std::vector <unsigned char> record_buffer; // for pack_row

  uint32_t max_row_length();

  unsigned int pack_row(const unsigned char *record);

public:

  FunctionCursor(drizzled::plugin::StorageEngine &engine,

                 drizzled::Table &table_arg);

  ~FunctionCursor() {}

  int open(const char *name, int mode, uint32_t test_if_locked);

  int close(void);

  int reset()

  {

    return extra(drizzled::HA_EXTRA_RESET_STATE);

  }

  int doStartTableScan(bool scan);

  /* get the next row and copy it into buf */

  int rnd_next(unsigned char *buf);

  /* locate row pointed to by pos, copy it into buf */

  int rnd_pos(unsigned char *buf, unsigned char *pos);

  int doEndTableScan();

  int extra(enum drizzled::ha_extra_function);

  /* record position of a record for reordering */

  void position(const unsigned char *record);

  int info(uint32_t flag);

  /**

   * @return an upper bound estimate for the number of rows in the table

   */

  drizzled::ha_rows estimate_rows_upper_bound()

  {

    return estimate_of_rows;

  }

  void get_auto_increment(uint64_t, uint64_t,

                          uint64_t,

                          uint64_t *,

                          uint64_t *)

  {}

};