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/* Copyright (C) 2000-2006 MySQL AB
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; version 2 of the License.
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 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 St, Fifth Floor, Boston, MA 02110-1301 USA */
#include "myisam_priv.h"
#include <drizzled/message/table.h>
using namespace drizzled;
/*
Read next row with the same key as previous read, but abort if
the key changes.
One may have done a write, update or delete of the previous row.
NOTE! Even if one changes the previous row, the next read is done
based on the position of the last used key!
*/
int mi_rnext_same(MI_INFO *info, unsigned char *buf)
{
int error;
uint32_t inx,not_used[2];
MI_KEYDEF *keyinfo;
if ((int) (inx=info->lastinx) < 0 || info->lastpos == HA_OFFSET_ERROR)
return(errno=HA_ERR_WRONG_INDEX);
keyinfo=info->s->keyinfo+inx;
if (fast_mi_readinfo(info))
return(errno);
switch (keyinfo->key_alg)
{
case message::Table::Index::BTREE:
default:
if (!(info->update & HA_STATE_RNEXT_SAME))
{
/* First rnext_same; Store old key */
memcpy(info->lastkey2,info->lastkey,info->last_rkey_length);
}
for (;;)
{
if ((error=_mi_search_next(info,keyinfo,info->lastkey,
info->lastkey_length,SEARCH_BIGGER,
info->s->state.key_root[inx])))
break;
if (ha_key_cmp(keyinfo->seg, info->lastkey, info->lastkey2,
info->last_rkey_length, SEARCH_FIND, not_used))
{
error=1;
errno=HA_ERR_END_OF_FILE;
info->lastpos= HA_OFFSET_ERROR;
break;
}
/* Skip rows that are inserted by other threads since we got a lock */
if (info->lastpos < info->state->data_file_length &&
(!info->index_cond_func || mi_check_index_cond(info, inx, buf)))
break;
}
}
/* Don't clear if database-changed */
info->update&= (HA_STATE_CHANGED | HA_STATE_ROW_CHANGED);
info->update|= HA_STATE_NEXT_FOUND | HA_STATE_RNEXT_SAME;
if (error)
{
if (errno == HA_ERR_KEY_NOT_FOUND)
errno=HA_ERR_END_OF_FILE;
}
else if (!buf)
{
return(info->lastpos==HA_OFFSET_ERROR ? errno : 0);
}
else if (!(*info->read_record)(info,info->lastpos,buf))
{
info->update|= HA_STATE_AKTIV; /* Record is read */
return(0);
}
return(errno);
} /* mi_rnext_same */
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