cursor_by_thread.h

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#ifndef CURSOR_BY_THREAD_H
#define CURSOR_BY_THREAD_H
 
/**
  @file storage/perfschema/cursor_by_thread.h
  Cursor CURSOR_BY_THREAD (declarations).
*/
 
#include "storage/perfschema/pfs_engine_table.h"
#include "storage/perfschema/pfs_instr.h"
#include "storage/perfschema/table_helper.h"
 
/**
  @addtogroup performance_schema_tables
  @{
*/
 
class PFS_index_threads : public PFS_engine_index {
 public:
  explicit PFS_index_threads(PFS_engine_key *key_1) : PFS_engine_index(key_1) {}
 
  PFS_index_threads(PFS_engine_key *key_1, PFS_engine_key *key_2)
      : PFS_engine_index(key_1, key_2) {}
 
  ~PFS_index_threads() override = default;
 
  virtual bool match(PFS_thread *pfs) = 0;
};
 
/** Cursor CURSOR_BY_THREAD. */
class cursor_by_thread : 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_thread(const PFS_engine_table_share *share);
 
 public:
  ~cursor_by_thread() override = default;
 
 protected:
  virtual int make_row(PFS_thread *thread) = 0;
 
 private:
  /** Current position. */
  PFS_simple_index m_pos;
  /** Next position. */
  PFS_simple_index m_next_pos;
 
 protected:
  PFS_index_threads *m_opened_index;
};
 
/** @} */
#endif