~drizzle-trunk/drizzle/development

/* Copyright (C) 2005 MySQL AB

  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; version 2 of the License.

  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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

#ifndef PLUGIN_BLACKHOLE_HA_BLACKHOLE_H

#define PLUGIN_BLACKHOLE_HA_BLACKHOLE_H

#include <drizzled/handler.h>

#include <mysys/thr_lock.h>

#define BLACKHOLE_MAX_KEY	64		/* Max allowed keys */

#define BLACKHOLE_MAX_KEY_SEG	16		/* Max segments for key */

#define BLACKHOLE_MAX_KEY_LENGTH 1000

/*

  Shared structure for correct LOCK operation

*/

struct st_blackhole_share {

  THR_LOCK lock;

  uint32_t use_count;

  uint32_t table_name_length;

  char table_name[1];

};

/*

  Class definition for the blackhole storage engine

  "Dumbest named feature ever"

*/

class ha_blackhole: public handler

{

  THR_LOCK_DATA lock;      /* MySQL lock */

  st_blackhole_share *share;

public:

  ha_blackhole(StorageEngine *engine, TableShare *table_arg);

  ~ha_blackhole()

  {}

  /*

    The name of the index type that will be used for display

    don't implement this method unless you really have indexes

  */

  const char *index_type(uint32_t key_number);

  uint64_t table_flags() const

  {

    return(HA_NULL_IN_KEY | HA_CAN_INDEX_BLOBS | HA_AUTO_PART_KEY);

  }

  uint32_t index_flags(uint32_t inx, uint32_t part, bool all_parts) const;

  /* The following defines can be increased if necessary */

  uint32_t max_supported_keys()          const { return BLACKHOLE_MAX_KEY; }

  uint32_t max_supported_key_length()    const { return BLACKHOLE_MAX_KEY_LENGTH; }

  uint32_t max_supported_key_part_length() const { return BLACKHOLE_MAX_KEY_LENGTH; }

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

  int close(void);

  int write_row(unsigned char * buf);

  int rnd_init(bool scan);

  int rnd_next(unsigned char *buf);

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

  int index_read_map(unsigned char * buf, const unsigned char * key, key_part_map keypart_map,

                     enum ha_rkey_function find_flag);

  int index_read_idx_map(unsigned char * buf, uint32_t idx, const unsigned char * key,

                         key_part_map keypart_map,

                         enum ha_rkey_function find_flag);

  int index_read_last_map(unsigned char * buf, const unsigned char * key, key_part_map keypart_map);

  int index_next(unsigned char * buf);

  int index_prev(unsigned char * buf);

  int index_first(unsigned char * buf);

  int index_last(unsigned char * buf);

  void position(const unsigned char *record);

  int info(uint32_t flag);

  int external_lock(Session *session, int lock_type);

  THR_LOCK_DATA **store_lock(Session *session,

                             THR_LOCK_DATA **to,

                             enum thr_lock_type lock_type);

};

#endif /* PLUGIN_BLACKHOLE_HA_BLACKHOLE_H */