/* Copyright (c) 2010, 2012, 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 as published by
  the Free Software Foundation; version 2 of the License.

  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 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, 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)
  {
    setup_object_hash_inited= false;
    lf_hash_destroy(&setup_object_hash);
  }
}

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;
}

/** @} */