コード例 #1
0
static int rtree_delete_req(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key, 
                           uint key_length, my_off_t page, uint *page_size, 
                           stPageList *ReinsertList, int level)
{
  uchar *k;
  uchar *last;
  ulong i;
  uint nod_flag;
  uchar *page_buf;
  int res;
  DBUG_ENTER("rtree_delete_req");

  if (!(page_buf = (uchar*)my_alloca((uint)keyinfo->block_length)))
  {
    my_errno = HA_ERR_OUT_OF_MEM;
    DBUG_RETURN(-1); /* purecov: inspected */
  }
  if (!_mi_fetch_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf, 0))
    goto err1;
  nod_flag = mi_test_if_nod(page_buf);
  DBUG_PRINT("rtree", ("page: %lu  level: %d  nod_flag: %u",
                       (ulong) page, level, nod_flag));

  k = rt_PAGE_FIRST_KEY(page_buf, nod_flag);
  last = rt_PAGE_END(page_buf);

  for (i = 0; k < last; k = rt_PAGE_NEXT_KEY(k, key_length, nod_flag), ++i)
  {
    if (nod_flag)
    { 
      /* not leaf */
      if (!rtree_key_cmp(keyinfo->seg, key, k, key_length, MBR_WITHIN))
      {
        switch ((res = rtree_delete_req(info, keyinfo, key, key_length, 
                  _mi_kpos(nod_flag, k), page_size, ReinsertList, level + 1)))
        {
          case 0: /* deleted */
          { 
            /* test page filling */
            if (*page_size + key_length >= rt_PAGE_MIN_SIZE(keyinfo->block_length)) 
            { 
              /* OK */
              /* Calculate a new key value (MBR) for the shrinked block. */
              if (rtree_set_key_mbr(info, keyinfo, k, key_length, 
                                  _mi_kpos(nod_flag, k)))
                goto err1;
              if (_mi_write_keypage(info, keyinfo, page,
                                    DFLT_INIT_HITS, page_buf))
                goto err1;
            }
            else
            { 
              /*
                Too small: delete key & add it descendant to reinsert list.
                Store position and level of the block so that it can be
                accessed later for inserting the remaining keys.
              */
              DBUG_PRINT("rtree", ("too small. move block to reinsert list"));
              if (rtree_fill_reinsert_list(ReinsertList, _mi_kpos(nod_flag, k),
                                           level + 1))
                goto err1;
              /*
                Delete the key that references the block. This makes the
                block disappear from the index. Hence we need to insert
                its remaining keys later. Note: if the block is a branch
                block, we do not only remove this block, but the whole
                subtree. So we need to re-insert its keys on the same
                level later to reintegrate the subtrees.
              */
              rtree_delete_key(info, page_buf, k, key_length, nod_flag);
              if (_mi_write_keypage(info, keyinfo, page,
                                    DFLT_INIT_HITS, page_buf))
                goto err1;
              *page_size = mi_getint(page_buf);
            }
            
            goto ok;
          }
          case 1: /* not found - continue searching */
          {
            break;
          }
          case 2: /* vacuous case: last key in the leaf */
          {
            rtree_delete_key(info, page_buf, k, key_length, nod_flag);
            if (_mi_write_keypage(info, keyinfo, page,
                                  DFLT_INIT_HITS, page_buf))
              goto err1;
            *page_size = mi_getint(page_buf);
            res = 0;
            goto ok;
          }
          default: /* error */
          case -1:
          {
            goto err1;
          }
        }
      }
    }
    else  
    {
      /* leaf */
      if (!rtree_key_cmp(keyinfo->seg, key, k, key_length, MBR_EQUAL | MBR_DATA))
      {
        rtree_delete_key(info, page_buf, k, key_length, nod_flag);
        *page_size = mi_getint(page_buf);
        if (*page_size == 2) 
        {
          /* last key in the leaf */
          res = 2;
          if (_mi_dispose(info, keyinfo, page, DFLT_INIT_HITS))
            goto err1;
        }
        else
        {
          res = 0;
          if (_mi_write_keypage(info, keyinfo, page, DFLT_INIT_HITS, page_buf))
            goto err1;
        }
        goto ok;
      }
    }
  }
  res = 1;

ok:
  my_afree((uchar*)page_buf);
  DBUG_RETURN(res);

err1:
  my_afree((uchar*)page_buf);
  DBUG_RETURN(-1); /* purecov: inspected */
}
コード例 #2
0
int rtree_split_page(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *page, uchar *key, 
                     uint key_length, my_off_t *new_page_offs)
{
  int n1, n2; /* Number of items in groups */

  SplitStruct *task;
  SplitStruct *cur;
  SplitStruct *stop;
  double *coord_buf;
  double *next_coord;
  int n_dim;
  uchar *source_cur, *cur1, *cur2;
  uchar *new_page= info->buff;
  int err_code= 0;
  uint nod_flag= mi_test_if_nod(page);
  uint full_length= key_length + (nod_flag ? nod_flag : 
                                  info->s->base.rec_reflength);
  int max_keys= (mi_getint(page)-2) / (full_length);
  DBUG_ENTER("rtree_split_page");
  DBUG_PRINT("rtree", ("splitting block"));

  n_dim = keyinfo->keysegs / 2;
  
  if (!(coord_buf= (double*) my_alloca(n_dim * 2 * sizeof(double) *
                                       (max_keys + 1 + 4) +
                                       sizeof(SplitStruct) * (max_keys + 1))))
    DBUG_RETURN(-1); /* purecov: inspected */

  task= (SplitStruct *)(coord_buf + n_dim * 2 * (max_keys + 1 + 4));

  next_coord = coord_buf;
 
  stop = task + max_keys;
  source_cur = rt_PAGE_FIRST_KEY(page, nod_flag);

  for (cur = task; cur < stop; ++cur, source_cur = rt_PAGE_NEXT_KEY(source_cur, 
       key_length, nod_flag))
  {
    cur->coords = reserve_coords(&next_coord, n_dim);
    cur->key = source_cur;
    rtree_d_mbr(keyinfo->seg, source_cur, key_length, cur->coords);
  }

  cur->coords = reserve_coords(&next_coord, n_dim);
  rtree_d_mbr(keyinfo->seg, key, key_length, cur->coords);
  cur->key = key;

  if (split_rtree_node(task, max_keys + 1,
       mi_getint(page) + full_length + 2, full_length, 
       rt_PAGE_MIN_SIZE(keyinfo->block_length),
       2, 2, &next_coord, n_dim))
  {
    err_code = 1;
    goto split_err;
  }

  info->buff_used= 1;
  stop = task + (max_keys + 1);
  cur1 = rt_PAGE_FIRST_KEY(page, nod_flag);
  cur2 = rt_PAGE_FIRST_KEY(new_page, nod_flag);

  n1= n2 = 0;
  for (cur = task; cur < stop; ++cur)
  {
    uchar *to;
    if (cur->n_node == 1)
    {
      to = cur1;
      cur1 = rt_PAGE_NEXT_KEY(cur1, key_length, nod_flag);
      ++n1;
    }
    else
    {
      to = cur2;
      cur2 = rt_PAGE_NEXT_KEY(cur2, key_length, nod_flag);
      ++n2;
    }
    if (to != cur->key)
      memcpy(to - nod_flag, cur->key - nod_flag, full_length);
  }
 
  mi_putint(page, 2 + n1 * full_length, nod_flag);
  mi_putint(new_page, 2 + n2 * full_length, nod_flag);

  if ((*new_page_offs= _mi_new(info, keyinfo, DFLT_INIT_HITS)) == 
                                                               HA_OFFSET_ERROR)
    err_code= -1;
  else
    err_code= _mi_write_keypage(info, keyinfo, *new_page_offs,
                                DFLT_INIT_HITS, new_page);
  DBUG_PRINT("rtree", ("split new block: %lu", (ulong) *new_page_offs));

split_err:
  my_afree((uchar*) coord_buf);
  DBUG_RETURN(err_code);
}