cursor_by_host.h

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  */

#ifndef CURSOR_BY_HOST_H
#define CURSOR_BY_HOST_H

/**
  @file storage/perfschema/cursor_by_host.h
  Cursor CURSOR_BY_HOST (declarations).
*/

#include "storage/perfschema/pfs_engine_table.h"
#include "storage/perfschema/pfs_host.h"
#include "storage/perfschema/table_helper.h"

/**
  @addtogroup performance_schema_tables
  @{
*/

class PFS_index_hosts : public PFS_engine_index {
 public:
  explicit PFS_index_hosts(PFS_engine_key *key_1) : PFS_engine_index(key_1) {}

  ~PFS_index_hosts() override = default;

  virtual bool match(PFS_host *pfs) = 0;
};

/** Cursor CURSOR_BY_HOST. */
class cursor_by_host : public PFS_engine_table {
 public:
  static ha_rows get_row_count();

  void reset_position() override;

  int rnd_next() override;
  int rnd_pos(const void *pos) override;

  int index_next() override;

 protected:
  explicit cursor_by_host(const PFS_engine_table_share *share);

 public:
  ~cursor_by_host() override = default;

 protected:
  virtual int make_row(PFS_host *host) = 0;

 private:
  /** Current position. */
  PFS_simple_index m_pos;
  /** Next position. */
  PFS_simple_index m_next_pos;

 protected:
  PFS_index_hosts *m_opened_index;
};

/** @} */
#endif