/* Copyright (c) 2000, 2002-2007 MySQL AB
   Use is subject to license terms

   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 */

/* Check that heap-structure is ok */

#include "heapdef.h"

static int check_one_key(HP_KEYDEF *keydef, uint keynr, ulong records,
			 ulong blength, my_bool print_status);
static int check_one_rb_key(HP_INFO *info, uint keynr, ulong records,
			    my_bool print_status);


/*
  Check if keys and rows are ok in a heap table

  SYNOPSIS
    heap_check_heap()
    info		Table handler
    print_status	Prints some extra status

  NOTES
    Doesn't change the state of the table handler

  RETURN VALUES
    0	ok
    1 error
*/

int heap_check_heap(HP_INFO *info, my_bool print_status)
{
  int error;
  uint key;
  ulong records=0, deleted=0, pos, next_block;
  HP_SHARE *share=info->s;
  HP_INFO save_info= *info;			/* Needed because scan_init */
  DBUG_ENTER("heap_check_heap");

  for (error=key= 0 ; key < share->keys ; key++)
  {
    if (share->keydef[key].algorithm == HA_KEY_ALG_BTREE)
      error|= check_one_rb_key(info, key, share->records, print_status);
    else
      error|= check_one_key(share->keydef + key, key, share->records,
			    share->blength, print_status);
  }
  /*
    This is basicly the same code as in hp_scan, but we repeat it here to
    get shorter DBUG log file.
  */
  for (pos=next_block= 0 ; ; pos++)
  {
    if (pos < next_block)
    {
      info->current_ptr+= share->block.recbuffer;
    }
    else
    {
      next_block+= share->block.records_in_block;
      if (next_block >= share->records+share->deleted)
      {
	next_block= share->records+share->deleted;
	if (pos >= next_block)
	  break;				/* End of file */
      }
    }
    hp_find_record(info,pos);

    if (!info->current_ptr[share->reclength])
      deleted++;
    else
      records++;
  }

  if (records != share->records || deleted != share->deleted)
  {
    DBUG_PRINT("error",("Found rows: %lu (%lu)  deleted %lu (%lu)",
			records, (ulong) share->records,
                        deleted, (ulong) share->deleted));
    error= 1;
  }
  *info= save_info;
  DBUG_RETURN(error);
}


static int check_one_key(HP_KEYDEF *keydef, uint keynr, ulong records,
			 ulong blength, my_bool print_status)
{
  int error;
  ulong i,found,max_links,seek,links;
  ulong rec_link;				/* Only used with debugging */
  ulong hash_buckets_found;
  HASH_INFO *hash_info;

  error=0;
  hash_buckets_found= 0;
  for (i=found=max_links=seek=0 ; i < records ; i++)
  {
    hash_info=hp_find_hash(&keydef->block,i);
    if (hp_mask(hp_rec_hashnr(keydef, hash_info->ptr_to_rec),
		blength,records) == i)
    {
      found++;
      seek++;
      links=1;
      while ((hash_info=hash_info->next_key) && found < records + 1)
      {
	seek+= ++links;
	if ((rec_link = hp_mask(hp_rec_hashnr(keydef, hash_info->ptr_to_rec),
			        blength, records))
	    != i)
	{
	  DBUG_PRINT("error",
                     ("Record in wrong link: Link %lu  Record: 0x%lx  Record-link %lu",
                      i, (long) hash_info->ptr_to_rec, rec_link));
	  error=1;
	}
	else
	  found++;
      }
      if (links > max_links) max_links=links;
      hash_buckets_found++;
    }
  }
  if (found != records)
  {
    DBUG_PRINT("error",("Found %ld of %ld records", found, records));
    error=1;
  }
  if (keydef->hash_buckets != hash_buckets_found)
  {
    DBUG_PRINT("error",("Found %ld buckets, stats shows %ld buckets",
                        hash_buckets_found, (long) keydef->hash_buckets));
    error=1;
  }
  DBUG_PRINT("info",
	     ("records: %ld   seeks: %lu   max links: %lu   hitrate: %.2f   "
              "buckets: %lu",
	      records,seek,max_links,
	      (float) seek / (float) (records ? records : 1), 
              hash_buckets_found));
  if (print_status)
    printf("Key: %d  records: %ld   seeks: %lu   max links: %lu   "
           "hitrate: %.2f   buckets: %lu\n",
	   keynr, records, seek, max_links,
	   (float) seek / (float) (records ? records : 1), 
           hash_buckets_found);
  return error;
}

static int check_one_rb_key(HP_INFO *info, uint keynr, ulong records,
			    my_bool print_status)
{
  HP_KEYDEF *keydef= info->s->keydef + keynr;
  int error= 0;
  ulong found= 0;
  uchar *key, *recpos;
  uint key_length;
  uint not_used[2];
  
  if ((key= tree_search_edge(&keydef->rb_tree, info->parents,
			     &info->last_pos, offsetof(TREE_ELEMENT, left))))
  {
    do
    {
      memcpy(&recpos, key + (*keydef->get_key_length)(keydef,key), sizeof(uchar*));
      key_length= hp_rb_make_key(keydef, info->recbuf, recpos, 0);
      if (ha_key_cmp(keydef->seg, (uchar*) info->recbuf, (uchar*) key,
		     key_length, SEARCH_FIND | SEARCH_SAME, not_used))
      {
	error= 1;
	DBUG_PRINT("error",("Record in wrong link:  key: %u  Record: 0x%lx\n", 
			    keynr, (long) recpos));
      }
      else
	found++;
      key= tree_search_next(&keydef->rb_tree, &info->last_pos,
			    offsetof(TREE_ELEMENT, left), 
			    offsetof(TREE_ELEMENT, right));
    } while (key);
  }
  if (found != records)
  {
    DBUG_PRINT("error",("Found %lu of %lu records", found, records));
    error= 1;
  }
  if (print_status)
    printf("Key: %d  records: %ld\n", keynr, records);
  return error;
}
