/* Copyright (c) 2012, 2023, 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.

  This program is also distributed with certain software (including
  but not limited to OpenSSL) that is licensed under separate terms,
  as designated in a particular file or component or in included license
  documentation.  The authors of MySQL hereby grant you an additional
  permission to link the program and your derivative works with the
  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,
  51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

#ifndef TABLE_METADATA_LOCK_H
#define TABLE_METADATA_LOCK_H

/**
  @file storage/perfschema/table_md_locks.h
  Table METADATA_LOCKS (declarations).
*/

#include "pfs_column_types.h"
#include "pfs_engine_table.h"
#include "table_helper.h"

struct PFS_metadata_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. */
  PFS_object_row m_object;
};

/** Table PERFORMANCE_SCHEMA.METADATA_LOCKS. */
class table_metadata_locks : public PFS_engine_table
{
public:
  static PFS_engine_table_share_state m_share_state;
  /** Table share. */
  static PFS_engine_table_share m_share;
  static PFS_engine_table* create();
  static ha_rows get_row_count();

  virtual int rnd_next();
  virtual int rnd_pos(const void *pos);
  virtual void reset_position(void);

private:
  virtual int read_row_values(TABLE *table,
                              unsigned char *buf,
                              Field **fields,
                              bool read_all);

  table_metadata_locks();

public:
  ~table_metadata_locks()
  {}

private:
  void make_row(PFS_metadata_lock *pfs);

  /** Table share lock. */
  static THR_LOCK m_table_lock;
  /** Fields definition. */
  static TABLE_FIELD_DEF m_field_def;

  /** Current row. */
  row_metadata_lock m_row;
  /** True if the current row exists. */
  bool m_row_exists;
  /** Current position. */
  PFS_simple_index m_pos;
  /** Next position. */
  PFS_simple_index m_next_pos;
};

/** @} */
#endif
