Files
cdesktop/cde/lib/tt/mini_isam/isdel1key.c
2018-06-30 19:10:10 -06:00

94 lines
2.6 KiB
C

/*
* CDE - Common Desktop Environment
*
* Copyright (c) 1993-2012, The Open Group. All rights reserved.
*
* These libraries and programs are free software; you can
* redistribute them and/or modify them under the terms of the GNU
* Lesser General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* These libraries and programs are distributed in the hope that
* they will be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. See the GNU Lesser General Public License for more
* details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with these libraries and programs; if not, write
* to the Free Software Foundation, Inc., 51 Franklin Street, Fifth
* Floor, Boston, MA 02110-1301 USA
*/
/*%% (c) Copyright 1993, 1994 Hewlett-Packard Company */
/*%% (c) Copyright 1993, 1994 International Business Machines Corp. */
/*%% (c) Copyright 1993, 1994 Sun Microsystems, Inc. */
/*%% (c) Copyright 1993, 1994 Novell, Inc. */
/*%% $XConsortium: isdel1key.c /main/3 1995/10/23 11:37:24 rswiston $ */
/*
* Copyright (c) 1988 by Sun Microsystems, Inc.
*/
/*
* isdel1key.c
*
* Description:
* Delete a key entry from index
*
*
*/
#include "isam_impl.h"
void
_del1key(Fcb *fcb, Keydesc2 *pkeydesc2, char *record, Recno recnum)
{
char keybuf[MAXKEYSIZE];
Btree *btree;
char *pkey;
/*
* Special case when there is no primary key.
*/
if (pkeydesc2->k2_nparts == 0)
return;
memset((char *)keybuf, 0,pkeydesc2->k2_len);
_iskey_extract(pkeydesc2,record,keybuf);
strecno(recnum, keybuf);
btree = _isbtree_create(fcb, pkeydesc2);
_isbtree_search(btree, keybuf);
if (ALLOWS_DUPS2(pkeydesc2)) {
/*
* We must now scan all the duplicates till we found one with
* matching recno. We are positioned just before the first duplicate.
* Remember that the duplicates are ordered by their serial number.
*
* If too many duplicate entries exists, the performance will be
* poor.
*/
while ((pkey = _isbtree_next(btree)) != NULL) {
if (ldrecno(pkey + KEY_RECNO_OFF) == recnum)
break; /* We found the entry */
}
if (pkey == NULL)
_isfatal_error("_del1key() cannot find entry in B tree");
_isbtree_remove(btree);
}
else {
if ((pkey = _isbtree_current(btree)) == NULL ||
ldrecno(pkey + KEY_RECNO_OFF) != recnum)
_isfatal_error("_del1key() cannot find entry in B tree");
_isbtree_remove(btree);
}
_isbtree_destroy(btree);
}