freebsd-dev/lib/libc/db/btree/bt_page.c
Xin LI 9fc74a871c Minor changes from Berkeley DB 1.86 and further improvements from OpenBSD.
This does not include the new hash routines since they will cause problems
when reading old hash files.

Since mpool(3) has been changed, provide a compatibility shim for older
binaries.

Obtained from:	OpenBSD
2009-03-28 07:31:02 +00:00

95 lines
2.7 KiB
C

/*-
* Copyright (c) 1990, 1993, 1994
* 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.
* 4. 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[] = "@(#)bt_page.c 8.3 (Berkeley) 7/14/94";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/types.h>
#include <stdio.h>
#include <db.h>
#include "btree.h"
/*
* __bt_free --
* Put a page on the freelist.
*
* Parameters:
* t: tree
* h: page to free
*
* Returns:
* RET_ERROR, RET_SUCCESS
*
* Side-effect:
* mpool_put's the page.
*/
int
__bt_free(BTREE *t, PAGE *h)
{
/* Insert the page at the head of the free list. */
h->prevpg = P_INVALID;
h->nextpg = t->bt_free;
t->bt_free = h->pgno;
F_SET(t, B_METADIRTY);
/* Make sure the page gets written back. */
return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
}
/*
* __bt_new --
* Get a new page, preferably from the freelist.
*
* Parameters:
* t: tree
* npg: storage for page number.
*
* Returns:
* Pointer to a page, NULL on error.
*/
PAGE *
__bt_new(BTREE *t, pgno_t *npg)
{
PAGE *h;
if (t->bt_free != P_INVALID &&
(h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
*npg = t->bt_free;
t->bt_free = h->nextpg;
F_SET(t, B_METADIRTY);
return (h);
}
return (mpool_new(t->bt_mp, npg, MPOOL_PAGE_NEXT));
}