/* Copyright (c) 2008, 2010, Oracle and/or its affiliates. All rights reserved.

  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 */

/**
  @file storage/perfschema/table_sync_instances.cc
  Table MUTEX_INSTANCES, RWLOCK_INSTANCES
  and COND_INSTANCES (implementation).
*/

#include "my_global.h"
#include "my_pthread.h"
#include "pfs_instr.h"
#include "pfs_column_types.h"
#include "pfs_column_values.h"
#include "table_sync_instances.h"
#include "pfs_global.h"

THR_LOCK table_mutex_instances::m_table_lock;

static const TABLE_FIELD_TYPE mutex_field_types[]=
{
  {
    { C_STRING_WITH_LEN("NAME") },
    { C_STRING_WITH_LEN("varchar(128)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("OBJECT_INSTANCE_BEGIN") },
    { C_STRING_WITH_LEN("bigint(20)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("LOCKED_BY_THREAD_ID") },
    { C_STRING_WITH_LEN("bigint(20)") },
    { NULL, 0}
  }
};

TABLE_FIELD_DEF
table_mutex_instances::m_field_def=
{ 3, mutex_field_types };

PFS_engine_table_share
table_mutex_instances::m_share=
{
  { C_STRING_WITH_LEN("mutex_instances") },
  &pfs_readonly_acl,
  &table_mutex_instances::create,
  NULL, /* write_row */
  NULL, /* delete_all_rows */
  NULL, /* get_row_count */
  1000, /* records */
  sizeof(PFS_simple_index),
  &m_table_lock,
  &m_field_def,
  false /* checked */
};

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

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

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

int table_mutex_instances::rnd_next(void)
{
  PFS_mutex *pfs;

  for (m_pos.set_at(&m_next_pos); m_pos.m_index < mutex_max; m_pos.next())
  {
    pfs= &mutex_array[m_pos.m_index];
    if (pfs->m_lock.is_populated())
    {
      make_row(pfs);
      m_next_pos.set_after(&m_pos);
      return 0;
    }
  }

  return HA_ERR_END_OF_FILE;
}

int table_mutex_instances::rnd_pos(const void *pos)
{
  PFS_mutex *pfs;

  set_position(pos);
  DBUG_ASSERT(m_pos.m_index < mutex_max);
  pfs= &mutex_array[m_pos.m_index];
  if (pfs->m_lock.is_populated())
  {
    make_row(pfs);
    return 0;
  }

  return HA_ERR_RECORD_DELETED;
}

void table_mutex_instances::make_row(PFS_mutex *pfs)
{
  pfs_lock lock;
  PFS_mutex_class *safe_class;

  m_row_exists= false;

  /* Protect this reader against a mutex destroy */
  pfs->m_lock.begin_optimistic_lock(&lock);

  safe_class= sanitize_mutex_class(pfs->m_class);
  if (unlikely(safe_class == NULL))
    return;

  m_row.m_name= safe_class->m_name;
  m_row.m_name_length= safe_class->m_name_length;
  m_row.m_identity= pfs->m_identity;

  /* Protect this reader against a mutex unlock */
  PFS_thread *safe_owner= sanitize_thread(pfs->m_owner);
  if (safe_owner)
  {
    m_row.m_locked_by_thread_id= safe_owner->m_thread_internal_id;
    m_row.m_locked= true;
  }
  else
    m_row.m_locked= false;

  if (pfs->m_lock.end_optimistic_lock(&lock))
    m_row_exists= true;
}

int table_mutex_instances::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 */
  DBUG_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: /* NAME */
        set_field_varchar_utf8(f, m_row.m_name, m_row.m_name_length);
        break;
      case 1: /* OBJECT_INSTANCE */
        set_field_ulonglong(f, (intptr) m_row.m_identity);
        break;
      case 2: /* LOCKED_BY_THREAD_ID */
        if (m_row.m_locked)
          set_field_ulonglong(f, m_row.m_locked_by_thread_id);
        else
          f->set_null();
        break;
      default:
        DBUG_ASSERT(false);
      }
    }
  }

  return 0;
}

THR_LOCK table_rwlock_instances::m_table_lock;

static const TABLE_FIELD_TYPE rwlock_field_types[]=
{
  {
    { C_STRING_WITH_LEN("NAME") },
    { C_STRING_WITH_LEN("varchar(128)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("OBJECT_INSTANCE_BEGIN") },
    { C_STRING_WITH_LEN("bigint(20)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("WRITE_LOCKED_BY_THREAD_ID") },
    { C_STRING_WITH_LEN("bigint(20)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("READ_LOCKED_BY_COUNT") },
    { C_STRING_WITH_LEN("int(10)") },
    { NULL, 0}
  }
};

TABLE_FIELD_DEF
table_rwlock_instances::m_field_def=
{ 4, rwlock_field_types };

PFS_engine_table_share
table_rwlock_instances::m_share=
{
  { C_STRING_WITH_LEN("rwlock_instances") },
  &pfs_readonly_acl,
  &table_rwlock_instances::create,
  NULL, /* write_row */
  NULL, /* delete_all_rows */
  NULL, /* get_row_count */
  1000, /* records */
  sizeof(PFS_simple_index),
  &m_table_lock,
  &m_field_def,
  false /* checked */
};

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

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

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

int table_rwlock_instances::rnd_next(void)
{
  PFS_rwlock *pfs;

  for (m_pos.set_at(&m_next_pos); m_pos.m_index < rwlock_max; m_pos.next())
  {
    pfs= &rwlock_array[m_pos.m_index];
    if (pfs->m_lock.is_populated())
    {
      make_row(pfs);
      m_next_pos.set_after(&m_pos);
      return 0;
    }
  }

  return HA_ERR_END_OF_FILE;
}

int table_rwlock_instances::rnd_pos(const void *pos)
{
  PFS_rwlock *pfs;

  set_position(pos);
  DBUG_ASSERT(m_pos.m_index < rwlock_max);
  pfs= &rwlock_array[m_pos.m_index];
  if (pfs->m_lock.is_populated())
  {
    make_row(pfs);
    return 0;
  }

  return HA_ERR_RECORD_DELETED;
}

void table_rwlock_instances::make_row(PFS_rwlock *pfs)
{
  pfs_lock lock;
  PFS_rwlock_class *safe_class;

  m_row_exists= false;

  /* Protect this reader against a rwlock destroy */
  pfs->m_lock.begin_optimistic_lock(&lock);

  safe_class= sanitize_rwlock_class(pfs->m_class);
  if (unlikely(safe_class == NULL))
    return;

  m_row.m_name= safe_class->m_name;
  m_row.m_name_length= safe_class->m_name_length;
  m_row.m_identity= pfs->m_identity;

  /* Protect this reader against a rwlock unlock in the writer */
  PFS_thread *safe_writer= sanitize_thread(pfs->m_writer);
  if (safe_writer)
  {
    m_row.m_write_locked_by_thread_id= safe_writer->m_thread_internal_id;
    m_row.m_readers= 0;
    m_row.m_write_locked= true;
  }
  else
  {
    m_row.m_readers= pfs->m_readers;
    m_row.m_write_locked= false;
  }

  if (pfs->m_lock.end_optimistic_lock(&lock))
    m_row_exists= true;
}

int table_rwlock_instances::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 */
  DBUG_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: /* NAME */
        set_field_varchar_utf8(f, m_row.m_name, m_row.m_name_length);
        break;
      case 1: /* OBJECT_INSTANCE */
        set_field_ulonglong(f, (intptr) m_row.m_identity);
        break;
      case 2: /* WRITE_LOCKED_BY_THREAD_ID */
        if (m_row.m_write_locked)
          set_field_ulonglong(f, m_row.m_write_locked_by_thread_id);
        else
          f->set_null();
        break;
      case 3: /* READ_LOCKED_BY_COUNT */
        set_field_ulong(f, m_row.m_readers);
        break;
      default:
        DBUG_ASSERT(false);
      }
    }
  }

  return 0;
}

THR_LOCK table_cond_instances::m_table_lock;

static const TABLE_FIELD_TYPE cond_field_types[]=
{
  {
    { C_STRING_WITH_LEN("NAME") },
    { C_STRING_WITH_LEN("varchar(128)") },
    { NULL, 0}
  },
  {
    { C_STRING_WITH_LEN("OBJECT_INSTANCE_BEGIN") },
    { C_STRING_WITH_LEN("bigint(20)") },
    { NULL, 0}
  }
};

TABLE_FIELD_DEF
table_cond_instances::m_field_def=
{ 2, cond_field_types };

PFS_engine_table_share
table_cond_instances::m_share=
{
  { C_STRING_WITH_LEN("cond_instances") },
  &pfs_readonly_acl,
  &table_cond_instances::create,
  NULL, /* write_row */
  NULL, /* delete_all_rows */
  NULL, /* get_row_count */
  1000, /* records */
  sizeof(PFS_simple_index),
  &m_table_lock,
  &m_field_def,
  false /* checked */
};

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

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

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

int table_cond_instances::rnd_next(void)
{
  PFS_cond *pfs;

  for (m_pos.set_at(&m_next_pos); m_pos.m_index < cond_max; m_pos.next())
  {
    pfs= &cond_array[m_pos.m_index];
    if (pfs->m_lock.is_populated())
    {
      make_row(pfs);
      m_next_pos.set_after(&m_pos);
      return 0;
    }
  }

  return HA_ERR_END_OF_FILE;
}

int table_cond_instances::rnd_pos(const void *pos)
{
  PFS_cond *pfs;

  set_position(pos);
  DBUG_ASSERT(m_pos.m_index < cond_max);
  pfs= &cond_array[m_pos.m_index];
  if (pfs->m_lock.is_populated())
  {
    make_row(pfs);
    return 0;
  }

  return HA_ERR_RECORD_DELETED;
}

void table_cond_instances::make_row(PFS_cond *pfs)
{
  pfs_lock lock;
  PFS_cond_class *safe_class;

  m_row_exists= false;

  /* Protect this reader against a cond destroy */
  pfs->m_lock.begin_optimistic_lock(&lock);

  safe_class= sanitize_cond_class(pfs->m_class);
  if (unlikely(safe_class == NULL))
    return;

  m_row.m_name= safe_class->m_name;
  m_row.m_name_length= safe_class->m_name_length;
  m_row.m_identity= pfs->m_identity;

  if (pfs->m_lock.end_optimistic_lock(&lock))
    m_row_exists= true;
}

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

  if (unlikely(! m_row_exists))
    return HA_ERR_RECORD_DELETED;

  /* Set the null bits */
  DBUG_ASSERT(table->s->null_bytes == 0);

  for (; (f= *fields) ; fields++)
  {
    if (read_all || bitmap_is_set(table->read_set, f->field_index))
    {
      switch(f->field_index)
      {
      case 0: /* NAME */
        set_field_varchar_utf8(f, m_row.m_name, m_row.m_name_length);
        break;
      case 1: /* OBJECT_INSTANCE */
        set_field_ulonglong(f, (intptr) m_row.m_identity);
        break;
      default:
        DBUG_ASSERT(false);
      }
    }
  }

  return 0;
}

