table_md_locks.h

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/* Copyright (c) 2012, 2022, Oracle and/or its affiliates.
 
  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License, version 2.0,
  as published by the Free Software Foundation.
 
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  as designated in a particular file or component or in included license
  documentation.  The authors of MySQL hereby grant you an additional
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  separately licensed software that they have included with MySQL.
 
  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, version 2.0, 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., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */
 
#ifndef TABLE_METADATA_LOCK_H
#define TABLE_METADATA_LOCK_H
 
/**
  @file storage/perfschema/table_md_locks.h
  Table METADATA_LOCKS (declarations).
*/
 
#include <sys/types.h>
 
#include "my_base.h"
#include "mysql/components/services/bits/psi_mdl_bits.h"
#include "storage/perfschema/pfs_column_types.h"
#include "storage/perfschema/pfs_engine_table.h"
#include "storage/perfschema/table_helper.h"
 
class Field;
class Plugin_table;
struct PFS_metadata_lock;
struct TABLE;
struct THR_LOCK;
 
/**
  @addtogroup performance_schema_tables
  @{
*/
 
/** A row of table PERFORMANCE_SCHEMA.MUTEX_INSTANCES. */
struct row_metadata_lock {
  /** Column OBJECT_INSTANCE_BEGIN. */
  const void *m_identity;
  opaque_mdl_type m_mdl_type;
  opaque_mdl_duration m_mdl_duration;
  opaque_mdl_status m_mdl_status;
  /** Column SOURCE. */
  char m_source[COL_SOURCE_SIZE];
  /** Length in bytes of @c m_source. */
  uint m_source_length;
  /** Column OWNER_THREAD_ID. */
  ulong m_owner_thread_id;
  /** Column OWNER_EVENT_ID. */
  ulong m_owner_event_id;
  /** Columns OBJECT_TYPE, OBJECT_SCHEMA, OBJECT_NAME, COLUMN_NAME. */
  PFS_column_row m_object;
};
 
class PFS_index_metadata_locks : public PFS_engine_index {
 public:
  explicit PFS_index_metadata_locks(PFS_engine_key *key_1)
      : PFS_engine_index(key_1) {}
 
  PFS_index_metadata_locks(PFS_engine_key *key_1, PFS_engine_key *key_2)
      : PFS_engine_index(key_1, key_2) {}
 
  PFS_index_metadata_locks(PFS_engine_key *key_1, PFS_engine_key *key_2,
                           PFS_engine_key *key_3, PFS_engine_key *key_4)
      : PFS_engine_index(key_1, key_2, key_3, key_4) {}
 
  ~PFS_index_metadata_locks() override = default;
 
  virtual bool match(const PFS_metadata_lock *pfs) = 0;
};
 
class PFS_index_metadata_locks_by_instance : public PFS_index_metadata_locks {
 public:
  PFS_index_metadata_locks_by_instance()
      : PFS_index_metadata_locks(&m_key), m_key("OBJECT_INSTANCE_BEGIN") {}
 
  ~PFS_index_metadata_locks_by_instance() override = default;
 
  bool match(const PFS_metadata_lock *pfs) override;
 
 private:
  PFS_key_object_instance m_key;
};
 
class PFS_index_metadata_locks_by_object : public PFS_index_metadata_locks {
 public:
  PFS_index_metadata_locks_by_object()
      : PFS_index_metadata_locks(&m_key_1, &m_key_2, &m_key_3, &m_key_4),
        m_key_1("OBJECT_TYPE"),
        m_key_2("OBJECT_SCHEMA"),
        m_key_3("OBJECT_NAME"),
        m_key_4("COLUMN_NAME") {}
 
  ~PFS_index_metadata_locks_by_object() override = default;
 
  bool match(const PFS_metadata_lock *pfs) override;
 
 private:
  PFS_key_object_type m_key_1;
  PFS_key_object_schema m_key_2;
  PFS_key_object_name m_key_3;
  PFS_key_column_name m_key_4;
};
 
class PFS_index_metadata_locks_by_owner : public PFS_index_metadata_locks {
 public:
  PFS_index_metadata_locks_by_owner()
      : PFS_index_metadata_locks(&m_key_1, &m_key_2),
        m_key_1("OWNER_THREAD_ID"),
        m_key_2("OWNER_EVENT_ID") {}
 
  ~PFS_index_metadata_locks_by_owner() override = default;
 
  bool match(const PFS_metadata_lock *pfs) override;
 
 private:
  PFS_key_thread_id m_key_1;
  PFS_key_event_id m_key_2;
};
 
/** Table PERFORMANCE_SCHEMA.METADATA_LOCKS. */
class table_metadata_locks : public PFS_engine_table {
 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(void) override;
 
  int rnd_next() override;
  int rnd_pos(const void *pos) override;
 
  int index_init(uint idx, bool sorted) override;
  int index_next() override;
 
 private:
  int read_row_values(TABLE *table, unsigned char *buf, Field **fields,
                      bool read_all) override;
  table_metadata_locks();
 
 public:
  ~table_metadata_locks() override = default;
 
 private:
  int make_row(PFS_metadata_lock *pfs);
 
  /** Table share lock. */
  static THR_LOCK m_table_lock;
  /** Table definition. */
  static Plugin_table m_table_def;
 
  /** Current row. */
  row_metadata_lock m_row;
  /** Current position. */
  PFS_simple_index m_pos;
  /** Next position. */
  PFS_simple_index m_next_pos;
 
 protected:
  PFS_index_metadata_locks *m_opened_index;
};
 
/** @} */
#endif