8a16b7a18f
Mainly focus on files that use BSD 3-Clause license. The Software Package Data Exchange (SPDX) group provides a specification to make it easier for automated tools to detect and summarize well known opensource licenses. We are gradually adopting the specification, noting that the tags are considered only advisory and do not, in any way, superceed or replace the license texts. Special thanks to Wind River for providing access to "The Duke of Highlander" tool: an older (2014) run over FreeBSD tree was useful as a starting point.
124 lines
3.6 KiB
C
124 lines
3.6 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*
|
|
* Copyright (c) 1990, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#if defined(LIBC_SCCS) && !defined(lint)
|
|
static char sccsid[] = "@(#)rec_search.c 8.4 (Berkeley) 7/14/94";
|
|
#endif /* LIBC_SCCS and not lint */
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <errno.h>
|
|
#include <stdio.h>
|
|
|
|
#include <db.h>
|
|
#include "recno.h"
|
|
|
|
/*
|
|
* __REC_SEARCH -- Search a btree for a key.
|
|
*
|
|
* Parameters:
|
|
* t: tree to search
|
|
* recno: key to find
|
|
* op: search operation
|
|
*
|
|
* Returns:
|
|
* EPG for matching record, if any, or the EPG for the location of the
|
|
* key, if it were inserted into the tree.
|
|
*
|
|
* Returns:
|
|
* The EPG for matching record, if any, or the EPG for the location
|
|
* of the key, if it were inserted into the tree, is entered into
|
|
* the bt_cur field of the tree. A pointer to the field is returned.
|
|
*/
|
|
EPG *
|
|
__rec_search(BTREE *t, recno_t recno, enum SRCHOP op)
|
|
{
|
|
indx_t idx;
|
|
PAGE *h;
|
|
EPGNO *parent;
|
|
RINTERNAL *r;
|
|
pgno_t pg;
|
|
indx_t top;
|
|
recno_t total;
|
|
int sverrno;
|
|
|
|
BT_CLR(t);
|
|
for (pg = P_ROOT, total = 0;;) {
|
|
if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
|
|
goto err;
|
|
if (h->flags & P_RLEAF) {
|
|
t->bt_cur.page = h;
|
|
t->bt_cur.index = recno - total;
|
|
return (&t->bt_cur);
|
|
}
|
|
for (idx = 0, top = NEXTINDEX(h);;) {
|
|
r = GETRINTERNAL(h, idx);
|
|
if (++idx == top || total + r->nrecs > recno)
|
|
break;
|
|
total += r->nrecs;
|
|
}
|
|
|
|
BT_PUSH(t, pg, idx - 1);
|
|
|
|
pg = r->pgno;
|
|
switch (op) {
|
|
case SDELETE:
|
|
--GETRINTERNAL(h, (idx - 1))->nrecs;
|
|
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
|
break;
|
|
case SINSERT:
|
|
++GETRINTERNAL(h, (idx - 1))->nrecs;
|
|
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
|
break;
|
|
case SEARCH:
|
|
mpool_put(t->bt_mp, h, 0);
|
|
break;
|
|
}
|
|
|
|
}
|
|
/* Try and recover the tree. */
|
|
err: sverrno = errno;
|
|
if (op != SEARCH)
|
|
while ((parent = BT_POP(t)) != NULL) {
|
|
if ((h = mpool_get(t->bt_mp, parent->pgno, 0)) == NULL)
|
|
break;
|
|
if (op == SINSERT)
|
|
--GETRINTERNAL(h, parent->index)->nrecs;
|
|
else
|
|
++GETRINTERNAL(h, parent->index)->nrecs;
|
|
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
|
}
|
|
errno = sverrno;
|
|
return (NULL);
|
|
}
|