/* 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.

  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, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

/**
  @file storage/perfschema/table_table_handles.cc
  Table TABLE_TABLE_HANDLES (implementation).
*/

#include "my_global.h"
#include "my_thread.h"
#include "pfs_instr_class.h"
#include "pfs_column_types.h"
#include "pfs_column_values.h"
#include "table_table_handles.h"
#include "pfs_global.h"
#include "pfs_stat.h"
#include "pfs_buffer_container.h"
#include "field.h"

THR_LOCK table_table_handles::m_table_lock;

PFS_engine_table_share_state
table_table_handles::m_share_state = {
  false /* m_checked */
};

PFS_engine_table_share
table_table_handles::m_share=
{
  { C_STRING_WITH_LEN("table_handles") },
  &pfs_readonly_acl,
  table_table_handles::create,
  NULL, /* write_row */
  NULL, /* delete_all_rows */
  table_table_handles::get_row_count,
  sizeof(PFS_simple_index),
  &m_table_lock,
  { C_STRING_WITH_LEN("CREATE TABLE table_handles("
  "OBJECT_TYPE VARCHAR(64) not null comment 'The table opened by a table handle.',"
  "OBJECT_SCHEMA VARCHAR(64) not null comment 'The schema that contains the object.',"
  "OBJECT_NAME VARCHAR(64) not null comment 'The name of the instrumented object.',"
  "OBJECT_INSTANCE_BEGIN BIGINT unsigned not null comment 'The table handle address in memory.',"
  "OWNER_THREAD_ID BIGINT unsigned comment 'The thread owning the table handle.',"
  "OWNER_EVENT_ID BIGINT unsigned comment 'The event which caused the table handle to be opened.',"
  "INTERNAL_LOCK VARCHAR(64) comment 'The table lock used at the SQL level.',"
  "EXTERNAL_LOCK VARCHAR(64) comment 'The table lock used at the storage engine level.')") },
  false, /* m_perpetual */
  false, /* m_optional */
  &m_share_state
};

PFS_engine_table*
table_table_handles::create(void)
{
  return new table_table_handles();
}

ha_rows
table_table_handles::get_row_count(void)
{
  return global_table_container.get_row_count();
}

table_table_handles::table_table_handles()
  : PFS_engine_table(&m_share, &m_pos),
    m_row_exists(false), m_pos(0), m_next_pos(0)
{}

void table_table_handles::reset_position(void)
{
  m_pos.m_index= 0;
  m_next_pos.m_index= 0;
}

int table_table_handles::rnd_init(bool scan)
{
  return 0;
}

int table_table_handles::rnd_next(void)
{
  PFS_table *pfs;

  m_pos.set_at(&m_next_pos);
  PFS_table_iterator it= global_table_container.iterate(m_pos.m_index);
  pfs= it.scan_next(& m_pos.m_index);
  if (pfs != NULL)
  {
    make_row(pfs);
    m_next_pos.set_after(&m_pos);
    return 0;
  }

  return HA_ERR_END_OF_FILE;
}

int
table_table_handles::rnd_pos(const void *pos)
{
  PFS_table *pfs;

  set_position(pos);

  pfs= global_table_container.get(m_pos.m_index);
  if (pfs != NULL)
  {
    make_row(pfs);
    return 0;
  }

  return HA_ERR_RECORD_DELETED;
}

void table_table_handles::make_row(PFS_table *table)
{
  pfs_optimistic_state lock;
  PFS_table_share *share;
  PFS_thread *thread;

  m_row_exists= false;

  table->m_lock.begin_optimistic_lock(&lock);

  share= sanitize_table_share(table->m_share);
  if (share == NULL)
    return;

  if (m_row.m_object.make_row(share))
    return;

  m_row.m_identity= table->m_identity;

  thread= sanitize_thread(table->m_thread_owner);
  if (thread != NULL)
  {
    m_row.m_owner_thread_id= thread->m_thread_internal_id;
    m_row.m_owner_event_id= table->m_owner_event_id;
  }
  else
  {
    m_row.m_owner_thread_id= 0;
    m_row.m_owner_event_id= 0;
  }

  m_row.m_internal_lock= table->m_internal_lock;
  m_row.m_external_lock= table->m_external_lock;

  if (! table->m_lock.end_optimistic_lock(&lock))
    return;

  m_row_exists= true;
}

int table_table_handles::read_row_values(TABLE *table,
                                         unsigned char *buf,
                                         Field **fields,
                                         bool read_all)
{
  Field *f;

  if (unlikely(! m_row_exists))
    return HA_ERR_RECORD_DELETED;

  /* Set the null bits */
  assert(table->s->null_bytes == 1);
  buf[0]= 0;

  for (; (f= *fields) ; fields++)
  {
    if (read_all || bitmap_is_set(table->read_set, f->field_index))
    {
      switch(f->field_index)
      {
      case 0: /* OBJECT_TYPE */
      case 1: /* SCHEMA_NAME */
      case 2: /* OBJECT_NAME */
        m_row.m_object.set_field(f->field_index, f);
        break;
      case 3: /* OBJECT_INSTANCE_BEGIN */
        set_field_ulonglong(f, (intptr) m_row.m_identity);
        break;
      case 4: /* OWNER_THREAD_ID */
        set_field_ulonglong(f, m_row.m_owner_thread_id);
        break;
      case 5: /* OWNER_EVENT_ID */
        set_field_ulonglong(f, m_row.m_owner_event_id);
        break;
      case 6: /* INTERNAL_LOCK */
        set_field_lock_type(f, m_row.m_internal_lock);
        break;
      case 7: /* EXTERNAL_LOCK */
        set_field_lock_type(f, m_row.m_external_lock);
        break;
      default:
        assert(false);
      }
    }
  }

  return 0;
}

