int myrg_rlast(MYRG_INFO *info, uchar *buf, int inx)
{
MYRG_TABLE *table;
MI_INFO *mi;
int err;
if (_myrg_init_queue(info,inx, HA_READ_KEY_OR_PREV))
return my_errno;
for (table=info->open_tables ; table < info->end_table ; table++)
{
if ((err=mi_rlast(table->table,NULL,inx)))
{
if (err == HA_ERR_END_OF_FILE)
continue;
return err;
}
/* adding to queue */
queue_insert(&(info->by_key),(uchar *)table);
}
/* We have done a read in all tables */
info->last_used_table=table;
if (!info->by_key.elements)
return HA_ERR_END_OF_FILE;
mi=(info->current_table=(MYRG_TABLE *)queue_top(&(info->by_key)))->table;
return _myrg_mi_read_record(mi,buf);
}
int myrg_rnext(MYRG_INFO *info, uchar *buf, int inx)
{
int err;
MI_INFO *mi;
if (!info->current_table)
return (HA_ERR_KEY_NOT_FOUND);
/* at first, do rnext for the table found before */
if ((err=mi_rnext(info->current_table->table,NULL,inx)))
{
if (err == HA_ERR_END_OF_FILE)
{
queue_remove(&(info->by_key),0);
if (!info->by_key.elements)
return HA_ERR_END_OF_FILE;
}
else
return err;
}
else
{
/* Found here, adding to queue */
queue_top(&(info->by_key))=(uchar *)(info->current_table);
queue_replaced(&(info->by_key));
}
/* now, mymerge's read_next is as simple as one queue_top */
mi=(info->current_table=(MYRG_TABLE *)queue_top(&(info->by_key)))->table;
return _myrg_mi_read_record(mi,buf);
}
int myrg_rkey(MYRG_INFO *info,uchar *buf,int inx, const uchar *key,
key_part_map keypart_map, enum ha_rkey_function search_flag)
{
uchar *key_buff;
uint pack_key_length;
uint16 last_used_keyseg;
MYRG_TABLE *table;
MI_INFO *mi;
int err;
DBUG_ENTER("myrg_rkey");
LINT_INIT(key_buff);
LINT_INIT(pack_key_length);
LINT_INIT(last_used_keyseg);
if (_myrg_init_queue(info,inx,search_flag))
DBUG_RETURN(my_errno);
for (table=info->open_tables ; table != info->end_table ; table++)
{
mi=table->table;
if (table == info->open_tables)
{
err=mi_rkey(mi, 0, inx, key, keypart_map, search_flag);
/* Get the saved packed key and packed key length. */
key_buff=(uchar*) mi->lastkey+mi->s->base.max_key_length;
pack_key_length=mi->pack_key_length;
last_used_keyseg= mi->last_used_keyseg;
}
else
{
mi->once_flags|= USE_PACKED_KEYS;
mi->last_used_keyseg= last_used_keyseg;
err=mi_rkey(mi, 0, inx, key_buff, pack_key_length, search_flag);
}
info->last_used_table=table+1;
if (err)
{
if (err == HA_ERR_KEY_NOT_FOUND)
continue;
DBUG_PRINT("exit", ("err: %d", err));
DBUG_RETURN(err);
}
/* adding to queue */
queue_insert(&(info->by_key),(uchar *)table);
}
DBUG_PRINT("info", ("tables with matches: %u", info->by_key.elements));
if (!info->by_key.elements)
DBUG_RETURN(HA_ERR_KEY_NOT_FOUND);
mi=(info->current_table=(MYRG_TABLE *)queue_top(&(info->by_key)))->table;
mi->once_flags|= RRND_PRESERVE_LASTINX;
DBUG_PRINT("info", ("using table no: %d",
(int) (info->current_table - info->open_tables + 1)));
DBUG_DUMP("result key", (uchar*) mi->lastkey, mi->lastkey_length);
DBUG_RETURN(_myrg_mi_read_record(mi,buf));
}
