/* Copyright (c) 2010, 2015, 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, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA */

/**
  @file storage/perfschema/pfs_setup_object.cc
  Performance schema setup object (implementation).
*/

#include "my_global.h"
#include "my_sys.h"
#include "my_base.h"
#include "sql_string.h"
#include "pfs.h"
#include "pfs_stat.h"
#include "pfs_instr.h"
#include "pfs_setup_object.h"
#include "pfs_global.h"

/**
  @addtogroup Performance_schema_buffers
  @{
*/

uint setup_objects_version= 0;

ulong setup_object_max;

PFS_setup_object *setup_object_array= NULL;

LF_HASH setup_object_hash;
static bool setup_object_hash_inited= false;

/**
  Initialize the setup object buffers.
  @param param                        sizing parameters
  @return 0 on success
*/
int init_setup_object(const PFS_global_param *param)
{
  setup_object_max= param->m_setup_object_sizing;

  setup_object_array= NULL;

  if (setup_object_max > 0)
  {
    setup_object_array= PFS_MALLOC_ARRAY(setup_object_max, sizeof(PFS_setup_object),
                                         PFS_setup_object, MYF(MY_ZEROFILL));
    if (unlikely(setup_object_array == NULL))
      return 1;
  }

  return 0;
}

/** Cleanup all the setup object buffers. */
void cleanup_setup_object(void)
{
  pfs_free(setup_object_array);
  setup_object_array= NULL;
  setup_object_max= 0;
}

C_MODE_START
static uchar *setup_object_hash_get_key(const uchar *entry, size_t *length,
                                        my_bool)
{
  const PFS_setup_object * const *typed_entry;
  const PFS_setup_object *setup_object;
  const void *result;
  typed_entry= reinterpret_cast<const PFS_setup_object* const *> (entry);
  DBUG_ASSERT(typed_entry != NULL);
  setup_object= *typed_entry;
  DBUG_ASSERT(setup_object != NULL);
  *length= setup_object->m_key.m_key_length;
  result= setup_object->m_key.m_hash_key;
  return const_cast<uchar*> (reinterpret_cast<const uchar*> (result));
}
C_MODE_END

/**
  Initialize the setup objects hash.
  @return 0 on success
*/
int init_setup_object_hash(void)
{
  if ((! setup_object_hash_inited) && (setup_object_max > 0))
  {
    lf_hash_init(&setup_object_hash, sizeof(PFS_setup_object*), LF_HASH_UNIQUE,
                 0, 0, setup_object_hash_get_key, &my_charset_bin);
    setup_object_hash.size= setup_object_max;
    setup_object_hash_inited= true;
  }
  return 0;
}

/** Cleanup the setup objects hash. */
void cleanup_setup_object_hash(void)
{
  if (setup_object_hash_inited)
  {
    lf_hash_destroy(&setup_object_hash);
    setup_object_hash_inited= false;
  }
}

static LF_PINS* get_setup_object_hash_pins(PFS_thread *thread)
{
  if (unlikely(thread->m_setup_object_hash_pins == NULL))
  {
    if (! setup_object_hash_inited)
      return NULL;
    thread->m_setup_object_hash_pins= lf_hash_get_pins(&setup_object_hash);
  }
  return thread->m_setup_object_hash_pins;
}

static void set_setup_object_key(PFS_setup_object_key *key,
                                 enum_object_type object_type,
                                 const char *schema, uint schema_length,
                                 const char *object, uint object_length)
{
  DBUG_ASSERT(schema_length <= NAME_LEN);
  DBUG_ASSERT(object_length <= NAME_LEN);

  char *ptr= &key->m_hash_key[0];
  ptr[0]= (char) object_type;
  ptr++;
  memcpy(ptr, schema, schema_length);
  ptr+= schema_length;
  ptr[0]= 0;
  ptr++;
  memcpy(ptr, object, object_length);
  ptr+= object_length;
  ptr[0]= 0;
  ptr++;
  key->m_key_length= ptr - &key->m_hash_key[0];
}

int insert_setup_object(enum_object_type object_type, const String *schema,
                        const String *object, bool enabled, bool timed)
{
  if (setup_object_max == 0)
    return HA_ERR_RECORD_FILE_FULL;

  PFS_thread *thread= PFS_thread::get_current_thread();
  if (unlikely(thread == NULL))
    return HA_ERR_OUT_OF_MEM;

  LF_PINS* pins= get_setup_object_hash_pins(thread);
  if (unlikely(pins == NULL))
    return HA_ERR_OUT_OF_MEM;

  static uint PFS_ALIGNED setup_object_monotonic_index= 0;
  uint index;
  uint attempts= 0;
  PFS_setup_object *pfs;

  while (++attempts <= setup_object_max)
  {
    /* See create_mutex() */
    index= PFS_atomic::add_u32(& setup_object_monotonic_index, 1) % setup_object_max;
    pfs= setup_object_array + index;

    if (pfs->m_lock.is_free())
    {
      if (pfs->m_lock.free_to_dirty())
      {
        set_setup_object_key(&pfs->m_key, object_type,
                             schema->ptr(), schema->length(),
                             object->ptr(), object->length());
        pfs->m_schema_name= &pfs->m_key.m_hash_key[1];
        pfs->m_schema_name_length= schema->length();
        pfs->m_object_name= pfs->m_schema_name + pfs->m_schema_name_length + 1;
        pfs->m_object_name_length= object->length();
        pfs->m_enabled= enabled;
        pfs->m_timed= timed;

        int res;
        res= lf_hash_insert(&setup_object_hash, pins, &pfs);
        if (likely(res == 0))
        {
          pfs->m_lock.dirty_to_allocated();
          setup_objects_version++;
          return 0;
        }

        pfs->m_lock.dirty_to_free();
        if (res > 0)
          return HA_ERR_FOUND_DUPP_KEY;
        /* OOM in lf_hash_insert */
        return HA_ERR_OUT_OF_MEM;
      }
    }
  }

  return HA_ERR_RECORD_FILE_FULL;
}

int delete_setup_object(enum_object_type object_type, const String *schema,
                        const String *object)
{
  PFS_thread *thread= PFS_thread::get_current_thread();
  if (unlikely(thread == NULL))
    return HA_ERR_OUT_OF_MEM;

  LF_PINS* pins= get_setup_object_hash_pins(thread);
  if (unlikely(pins == NULL))
    return HA_ERR_OUT_OF_MEM;

  PFS_setup_object_key key;
  set_setup_object_key(&key, object_type,
                       schema->ptr(), schema->length(),
                       object->ptr(), object->length());

  PFS_setup_object **entry;
  entry= reinterpret_cast<PFS_setup_object**>
    (lf_hash_search(&setup_object_hash, pins, key.m_hash_key, key.m_key_length));

  if (entry && (entry != MY_ERRPTR))
  {
    PFS_setup_object *pfs= *entry;
    lf_hash_delete(&setup_object_hash, pins, key.m_hash_key, key.m_key_length);
    pfs->m_lock.allocated_to_free();
  }

  lf_hash_search_unpin(pins);

  setup_objects_version++;
  return 0;
}

int reset_setup_object()
{
  PFS_thread *thread= PFS_thread::get_current_thread();
  if (unlikely(thread == NULL))
    return HA_ERR_OUT_OF_MEM;

  LF_PINS* pins= get_setup_object_hash_pins(thread);
  if (unlikely(pins == NULL))
    return HA_ERR_OUT_OF_MEM;

  PFS_setup_object *pfs= setup_object_array;
  PFS_setup_object *pfs_last= setup_object_array + setup_object_max;

  for ( ; pfs < pfs_last; pfs++)
  {
    if (pfs->m_lock.is_populated())
    {
      lf_hash_delete(&setup_object_hash, pins,
                     pfs->m_key.m_hash_key, pfs->m_key.m_key_length);
      pfs->m_lock.allocated_to_free();
    }
  }

  setup_objects_version++;
  return 0;
}

long setup_object_count()
{
  return setup_object_hash.count;
}

void lookup_setup_object(PFS_thread *thread,
                         enum_object_type object_type,
                         const char *schema_name, int schema_name_length,
                         const char *object_name, int object_name_length,
                         bool *enabled, bool *timed)
{
  PFS_setup_object_key key;
  PFS_setup_object **entry;
  PFS_setup_object *pfs;
  int i;

  /*
    The table io instrumentation uses "TABLE" and "TEMPORARY TABLE".
    SETUP_OBJECT uses "TABLE" for both concepts.
    There is no way to provide a different setup for:
    - TABLE foo.bar
    - TEMPORARY TABLE foo.bar
  */
  DBUG_ASSERT(object_type != OBJECT_TYPE_TEMPORARY_TABLE);

  LF_PINS* pins= get_setup_object_hash_pins(thread);
  if (unlikely(pins == NULL))
  {
    *enabled= false;
    *timed= false;
    return;
  }

  for (i= 1; i<=3; i++)
  {
    switch(i)
    {
    case 1:
      /* Lookup OBJECT_TYPE + OBJECT_SCHEMA + OBJECT_NAME in SETUP_OBJECTS */
      set_setup_object_key(&key,
                           object_type,
                           schema_name, schema_name_length,
                           object_name, object_name_length);
      break;
    case 2:
      /* Lookup OBJECT_TYPE + OBJECT_SCHEMA + "%" in SETUP_OBJECTS */
      set_setup_object_key(&key,
                           object_type,
                           schema_name, schema_name_length, "%", 1);
      break;
    case 3:
      /* Lookup OBJECT_TYPE + "%" + "%" in SETUP_OBJECTS */
      set_setup_object_key(&key, object_type, "%", 1, "%", 1);
      break;
    }
    entry= reinterpret_cast<PFS_setup_object**>
      (lf_hash_search(&setup_object_hash, pins, key.m_hash_key, key.m_key_length));

    if (entry && (entry != MY_ERRPTR))
    {
      pfs= *entry;
      *enabled= pfs->m_enabled;
      *timed= pfs->m_timed;
      lf_hash_search_unpin(pins);
      return;
    }

    lf_hash_search_unpin(pins);
  }
  *enabled= false;
  *timed= false;
  return;
}

/** @} */
