release/src/router/mysql/storage/myisam/rt_key.c

   1 /* Copyright (c) 2000, 2002-2005, 2007 MySQL AB
   2
   3    This program is free software; you can redistribute it and/or modify
   4    it under the terms of the GNU General Public License as published by
   5    the Free Software Foundation; version 2 of the License.
   6
   7    This program is distributed in the hope that it will be useful,
   8    but WITHOUT ANY WARRANTY; without even the implied warranty of
   9    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  10    GNU General Public License for more details.
  11
  12    You should have received a copy of the GNU General Public License
  13    along with this program; if not, write to the Free Software
  14    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA */
  15
  16 #include "myisamdef.h"
  17
  18 #ifdef HAVE_RTREE_KEYS
  19 #include "rt_index.h"
  20 #include "rt_key.h"
  21 #include "rt_mbr.h"
  22
  23 /*
  24   Add key to the page
  25
  26   RESULT VALUES
  27     -1  Error
  28     0   Not split
  29     1   Split
  30 */
  31
  32 int rtree_add_key(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
  33                   uint key_length, uchar *page_buf, my_off_t *new_page)
  34 {
  35   uint page_size = mi_getint(page_buf);
  36   uint nod_flag = mi_test_if_nod(page_buf);
  37   DBUG_ENTER("rtree_add_key");
  38
  39   if (page_size + key_length + info->s->base.rec_reflength <=
  40       keyinfo->block_length)
  41   {
  42     /* split won't be necessary */
  43     if (nod_flag)
  44     {
  45       /* save key */
  46       DBUG_ASSERT(_mi_kpos(nod_flag, key) < info->state->key_file_length);
  47       memcpy(rt_PAGE_END(page_buf), key - nod_flag, key_length + nod_flag);
  48       page_size += key_length + nod_flag;
  49     }
  50     else
  51     {
  52       /* save key */
  53       DBUG_ASSERT(_mi_dpos(info, nod_flag, key + key_length +
  54                            info->s->base.rec_reflength) <
  55                   info->state->data_file_length + info->s->base.pack_reclength);
  56       memcpy(rt_PAGE_END(page_buf), key, key_length +
  57                                          info->s->base.rec_reflength);
  58       page_size += key_length + info->s->base.rec_reflength;
  59     }
  60     mi_putint(page_buf, page_size, nod_flag);
  61     DBUG_RETURN(0);
  62   }
  63
  64   DBUG_RETURN((rtree_split_page(info, keyinfo, page_buf, key, key_length,
  65                                 new_page) ? -1 : 1));
  66 }
  67
  68 /*
  69   Delete key from the page
  70 */
  71 int rtree_delete_key(MI_INFO *info, uchar *page_buf, uchar *key,
  72                      uint key_length, uint nod_flag)
  73 {
  74   uint16 page_size = mi_getint(page_buf);
  75   uchar *key_start;
  76
  77   key_start= key - nod_flag;
  78   if (!nod_flag)
  79     key_length += info->s->base.rec_reflength;
  80
  81   memmove(key_start, key + key_length, page_size - key_length -
  82           (key - page_buf));
  83   page_size-= key_length + nod_flag;
  84
  85   mi_putint(page_buf, page_size, nod_flag);
  86   return 0;
  87 }
  88
  89
  90 /*
  91   Calculate and store key MBR
  92 */
  93
  94 int rtree_set_key_mbr(MI_INFO *info, MI_KEYDEF *keyinfo, uchar *key,
  95                       uint key_length, my_off_t child_page)
  96 {
  97   DBUG_ENTER("rtree_set_key_mbr");
  98
  99   if (!_mi_fetch_keypage(info, keyinfo, child_page,
 100                          DFLT_INIT_HITS, info->buff, 0))
 101     DBUG_RETURN(-1); /* purecov: inspected */
 102
 103   DBUG_RETURN(rtree_page_mbr(info, keyinfo->seg, info->buff, key, key_length));
 104 }
 105
 106 #endif /*HAVE_RTREE_KEYS*/