table_setup_meters.h

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#ifndef TABLE_SETUP_METERS_H
#define TABLE_SETUP_METERS_H
 
/**
  @file storage/perfschema/table_setup_meters.h
  Table SETUP_METERS (declarations).
*/
 
#include <sys/types.h>
 
#include "my_base.h"
#include "storage/perfschema/pfs_engine_table.h"
#include "storage/perfschema/table_helper.h"
 
class Field;
class Plugin_table;
struct PFS_instr_class;
struct PFS_meter_class;
struct TABLE;
struct THR_LOCK;
 
/**
  @addtogroup performance_schema_tables
  @{
*/
 
/** A row of PERFORMANCE_SCHEMA.SETUP_METERS. */
struct row_setup_meters {
  /** Columns NAME, ENABLED. */
  PFS_meter_class *m_instr_class;
 
  // materialized from PFS_meter_class
  const char *m_meter;
  uint m_meter_length;
  uint m_frequency;
  const char *m_description;
  uint m_description_length;
  bool m_enabled;
};
 
class PFS_index_setup_meters : public PFS_engine_index {
 public:
  explicit PFS_index_setup_meters(PFS_engine_key *key_1)
      : PFS_engine_index(key_1) {}
 
  ~PFS_index_setup_meters() override = default;
 
  virtual bool match(PFS_meter_class *pfs) = 0;
};
 
class PFS_index_setup_meters_by_name : public PFS_index_setup_meters {
 public:
  PFS_index_setup_meters_by_name()
      : PFS_index_setup_meters(&m_key), m_key("NAME") {}
 
  ~PFS_index_setup_meters_by_name() override = default;
 
  bool match(PFS_meter_class *pfs) override;
 
 private:
  PFS_key_meter_name m_key;
};
 
/** Position of a cursor, for meter iterations. */
struct PFS_meter_index {
  /** Current row index. */
  uint m_index;
 
  /**
    Constructor.
    @param index the index initial value.
  */
  explicit PFS_meter_index(uint index) : m_index(index) {}
 
  /**
    Set this index at a given position.
    @param index an index
  */
  void set_at(uint index) { m_index = index; }
 
  /**
    Set this index at a given position.
    @param other a position
   */
  void set_at(const PFS_meter_index *other) { m_index = other->m_index; }
 
  /**
    Set this index after a given position.
    @param other a position
  */
  void set_after(const PFS_meter_index *other) {
    m_index = other->m_index;
    next();
  }
 
  /** Set this index to the next record. */
  void next() {
    do {
      m_index++;
    } while (m_index < meter_class_max &&
             meter_class_array[m_index - 1].m_key == 0);
  }
};
 
/** Table PERFORMANCE_SCHEMA.SETUP_METERS. */
class table_setup_meters : public PFS_engine_table {
  typedef PFS_meter_index pos_t;
 
 public:
  /** Table share. */
  static PFS_engine_table_share m_share;
  static PFS_engine_table *create(PFS_engine_table_share *);
  static ha_rows get_row_count();
 
  void reset_position() override;
 
  int rnd_next() override;
  int rnd_pos(const void *pos) override;
 
  int index_init(uint idx, bool sorted) override;
  int index_next() override;
 
 protected:
  int read_row_values(TABLE *table, unsigned char *buf, Field **fields,
                      bool read_all) override;
 
  int update_row_values(TABLE *table, const unsigned char *old_buf,
                        unsigned char *new_buf, Field **fields) override;
 
  table_setup_meters();
 
 public:
  ~table_setup_meters() override = default;
 
 private:
  int make_row(PFS_meter_class *klass);
 
  /** Table share lock. */
  static THR_LOCK m_table_lock;
  /** Table definition. */
  static Plugin_table m_table_def;
 
  /** Current row. */
  row_setup_meters m_row;
  /** Current position. */
  pos_t m_pos;
  /** Next position. */
  pos_t m_next_pos;
 
  PFS_index_setup_meters *m_opened_index;
};
 
/** @} */
#endif