table_global_variable_attributes.h

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#ifndef TABLE_GLOBAL_VARIABLE_ATTRIBUTES_H
#define TABLE_GLOBAL_VARIABLE_ATTRIBUTES_H
 
/**
  @file storage/perfschema/table_global_variable_attributes.h
  Table GLOBAL_VARIABLE_ATTRIBUTES (declarations).
*/
 
#include <sys/types.h>
 
#include "my_base.h"
#include "my_inttypes.h"
#include "mysql/components/services/system_variable_source_type.h"
#include "mysql_com.h"
#include "storage/perfschema/pfs_column_types.h"
#include "storage/perfschema/pfs_engine_table.h"
#include "storage/perfschema/pfs_variable.h"
 
class Field;
class Plugin_table;
struct TABLE;
struct THR_LOCK;
 
/**
  A row of table
  PERFORMANCE_SCHEMA.GLOBAL_VARIABLE_ATTRIBUTES.
*/
 
struct row_global_variable_attributes {
  row_global_variable_attributes();
  row_global_variable_attributes(const sys_var *system_var,
                                 const char *attribute_name,
                                 const char *attribute_value);
  row_global_variable_attributes(const row_global_variable_attributes &other);
  row_global_variable_attributes &operator=(
      const row_global_variable_attributes &other);
 
  /** Column VARIABLE_NAME. */
  char m_variable_name[COL_OBJECT_NAME_SIZE];
  uint m_variable_name_length;
  /** Column ATTR_NAME. */
  char m_attr_name[COL_SHORT_NAME_SIZE];
  uint m_attr_name_length;
  /** Column ATTR_VALUE. */
  char m_attr_value[COL_INFO_SIZE];
  uint m_attr_value_length;
};
 
/** Table PERFORMANCE_SCHEMA.GLOBAL_VARIABLE_ATTRIBUTES. */
class table_global_variable_attributes : public PFS_engine_table {
  typedef PFS_simple_index pos_t;
  typedef Prealloced_array<row_global_variable_attributes,
                           SYSTEM_VARIABLE_PREALLOC>
      Variable_array;
 
 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();
 
  int rnd_init(bool scan) override;
  int rnd_next() override;
  int rnd_pos(const void *pos) override;
  void reset_position() override;
 
 protected:
  int read_row_values(TABLE *table, unsigned char *buf, Field **fields,
                      bool read_all) override;
  table_global_variable_attributes();
 
 public:
  ~table_global_variable_attributes() override = default;
 
 protected:
  /* Build sys_var tracker array. */
  bool init_sys_var_array();
  /* Build sys_var info cache. */
  int do_materialize_all();
 
  int make_row(const row_global_variable_attributes &row);
 
 private:
  /** Table share lock. */
  static THR_LOCK m_table_lock;
  /** Table definition. */
  static Plugin_table m_table_def;
 
  /* True when system variable descriptors array is complete. */
  bool m_initialized;
  /* Array of system variable descriptors. */
  System_variable_tracker::Array m_sys_var_tracker_array;
  /* Cache of materialized variables. */
  Variable_array m_cache;
  /* True when cache is complete. */
  bool m_materialized;
  /* Version of global hash/array. Changes when vars added/removed. */
  ulonglong m_version;
 
  /** Current row. */
  row_global_variable_attributes m_row;
  /** Current position. */
  pos_t m_pos;
  /** Next position. */
  pos_t m_next_pos;
};
 
#endif