MySQL 5.6.14 Source Code Document
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Groups Pages
myrg_rnext_same.c
1 /* Copyright (C) 2002, 2004 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 "myrg_def.h"
17 
18 
19 int myrg_rnext_same(MYRG_INFO *info, uchar *buf)
20 {
21  int err;
22  MI_INFO *mi;
23 
24  if (!info->current_table)
25  return (HA_ERR_KEY_NOT_FOUND);
26 
27  /* at first, do rnext for the table found before */
28  if ((err=mi_rnext_same(info->current_table->table,NULL)))
29  {
30  if (err == HA_ERR_END_OF_FILE)
31  {
32  queue_remove(&(info->by_key),0);
33  if (!info->by_key.elements)
34  return HA_ERR_END_OF_FILE;
35  }
36  else
37  return err;
38  }
39  else
40  {
41  /* Found here, adding to queue */
42  queue_top(&(info->by_key))=(uchar *)(info->current_table);
43  queue_replaced(&(info->by_key));
44  }
45 
46  /* now, mymerge's read_next is as simple as one queue_top */
47  mi=(info->current_table=(MYRG_TABLE *)queue_top(&(info->by_key)))->table;
48  return _myrg_mi_read_record(mi,buf);
49 }
50