2N/A/*-
2N/A * Copyright (c) 1990, 1993, 1994
2N/A * The Regents of the University of California. All rights reserved.
2N/A *
2N/A * Redistribution and use in source and binary forms, with or without
2N/A * modification, are permitted provided that the following conditions
2N/A * are met:
2N/A * 1. Redistributions of source code must retain the above copyright
2N/A * notice, this list of conditions and the following disclaimer.
2N/A * 2. Redistributions in binary form must reproduce the above copyright
2N/A * notice, this list of conditions and the following disclaimer in the
2N/A * documentation and/or other materials provided with the distribution.
2N/A * 3. All advertising materials mentioning features or use of this software
2N/A * must display the following acknowledgement:
2N/A * This product includes software developed by the University of
2N/A * California, Berkeley and its contributors.
2N/A * 4. Neither the name of the University nor the names of its contributors
2N/A * may be used to endorse or promote products derived from this software
2N/A * without specific prior written permission.
2N/A *
2N/A * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
2N/A * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
2N/A * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
2N/A * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
2N/A * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
2N/A * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
2N/A * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
2N/A * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
2N/A * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
2N/A * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
2N/A * SUCH DAMAGE.
2N/A */
2N/A
2N/A#if defined(LIBC_SCCS) && !defined(lint)
2N/Astatic char sccsid[] = "@(#)bt_page.c 8.4 (Berkeley) 11/2/95";
2N/A#endif /* LIBC_SCCS and not lint */
2N/A
2N/A#include <sys/types.h>
2N/A
2N/A#include <stdio.h>
2N/A
2N/A#include "db-int.h"
2N/A#include "btree.h"
2N/A
2N/A/*
2N/A * __bt_free --
2N/A * Put a page on the freelist.
2N/A *
2N/A * Parameters:
2N/A * t: tree
2N/A * h: page to free
2N/A *
2N/A * Returns:
2N/A * RET_ERROR, RET_SUCCESS
2N/A *
2N/A * Side-effect:
2N/A * mpool_put's the page.
2N/A */
2N/Aint
2N/A__bt_free(t, h)
2N/A BTREE *t;
2N/A PAGE *h;
2N/A{
2N/A /* Insert the page at the head of the free list. */
2N/A h->prevpg = P_INVALID;
2N/A h->nextpg = t->bt_free;
2N/A t->bt_free = h->pgno;
2N/A F_SET(t, B_METADIRTY);
2N/A
2N/A /* Make sure the page gets written back. */
2N/A return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
2N/A}
2N/A
2N/A/*
2N/A * __bt_new --
2N/A * Get a new page, preferably from the freelist.
2N/A *
2N/A * Parameters:
2N/A * t: tree
2N/A * npg: storage for page number.
2N/A *
2N/A * Returns:
2N/A * Pointer to a page, NULL on error.
2N/A */
2N/APAGE *
2N/A__bt_new(t, npg)
2N/A BTREE *t;
2N/A db_pgno_t *npg;
2N/A{
2N/A PAGE *h;
2N/A
2N/A if (t->bt_free != P_INVALID &&
2N/A (h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
2N/A *npg = t->bt_free;
2N/A t->bt_free = h->nextpg;
2N/A F_SET(t, B_METADIRTY);
2N/A return (h);
2N/A }
2N/A return (mpool_new(t->bt_mp, npg, MPOOL_PAGE_NEXT));
2N/A}