17c478bd9Sstevel@tonic-gate /*-
27c478bd9Sstevel@tonic-gate * Copyright (c) 1990, 1993, 1994
37c478bd9Sstevel@tonic-gate * The Regents of the University of California. All rights reserved.
47c478bd9Sstevel@tonic-gate *
57c478bd9Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without
67c478bd9Sstevel@tonic-gate * modification, are permitted provided that the following conditions
77c478bd9Sstevel@tonic-gate * are met:
87c478bd9Sstevel@tonic-gate * 1. Redistributions of source code must retain the above copyright
97c478bd9Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer.
107c478bd9Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright
117c478bd9Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the
127c478bd9Sstevel@tonic-gate * documentation and/or other materials provided with the distribution.
137c478bd9Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software
147c478bd9Sstevel@tonic-gate * must display the following acknowledgement:
157c478bd9Sstevel@tonic-gate * This product includes software developed by the University of
167c478bd9Sstevel@tonic-gate * California, Berkeley and its contributors.
177c478bd9Sstevel@tonic-gate * 4. Neither the name of the University nor the names of its contributors
187c478bd9Sstevel@tonic-gate * may be used to endorse or promote products derived from this software
197c478bd9Sstevel@tonic-gate * without specific prior written permission.
207c478bd9Sstevel@tonic-gate *
217c478bd9Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
227c478bd9Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
237c478bd9Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
247c478bd9Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
257c478bd9Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
267c478bd9Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
277c478bd9Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
287c478bd9Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
297c478bd9Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
307c478bd9Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
317c478bd9Sstevel@tonic-gate * SUCH DAMAGE.
327c478bd9Sstevel@tonic-gate */
337c478bd9Sstevel@tonic-gate
347c478bd9Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint)
357c478bd9Sstevel@tonic-gate static char sccsid[] = "@(#)bt_page.c 8.4 (Berkeley) 11/2/95";
367c478bd9Sstevel@tonic-gate #endif /* LIBC_SCCS and not lint */
377c478bd9Sstevel@tonic-gate
387c478bd9Sstevel@tonic-gate #include <sys/types.h>
397c478bd9Sstevel@tonic-gate
407c478bd9Sstevel@tonic-gate #include <stdio.h>
417c478bd9Sstevel@tonic-gate
427c478bd9Sstevel@tonic-gate #include "db-int.h"
437c478bd9Sstevel@tonic-gate #include "btree.h"
447c478bd9Sstevel@tonic-gate
457c478bd9Sstevel@tonic-gate /*
467c478bd9Sstevel@tonic-gate * __bt_free --
477c478bd9Sstevel@tonic-gate * Put a page on the freelist.
487c478bd9Sstevel@tonic-gate *
497c478bd9Sstevel@tonic-gate * Parameters:
507c478bd9Sstevel@tonic-gate * t: tree
517c478bd9Sstevel@tonic-gate * h: page to free
527c478bd9Sstevel@tonic-gate *
537c478bd9Sstevel@tonic-gate * Returns:
547c478bd9Sstevel@tonic-gate * RET_ERROR, RET_SUCCESS
557c478bd9Sstevel@tonic-gate *
567c478bd9Sstevel@tonic-gate * Side-effect:
577c478bd9Sstevel@tonic-gate * mpool_put's the page.
587c478bd9Sstevel@tonic-gate */
597c478bd9Sstevel@tonic-gate int
__bt_free(t,h)607c478bd9Sstevel@tonic-gate __bt_free(t, h)
617c478bd9Sstevel@tonic-gate BTREE *t;
627c478bd9Sstevel@tonic-gate PAGE *h;
637c478bd9Sstevel@tonic-gate {
647c478bd9Sstevel@tonic-gate /* Insert the page at the head of the free list. */
657c478bd9Sstevel@tonic-gate h->prevpg = P_INVALID;
667c478bd9Sstevel@tonic-gate h->nextpg = t->bt_free;
677c478bd9Sstevel@tonic-gate t->bt_free = h->pgno;
687c478bd9Sstevel@tonic-gate F_SET(t, B_METADIRTY);
697c478bd9Sstevel@tonic-gate
707c478bd9Sstevel@tonic-gate /* Make sure the page gets written back. */
717c478bd9Sstevel@tonic-gate return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
727c478bd9Sstevel@tonic-gate }
737c478bd9Sstevel@tonic-gate
747c478bd9Sstevel@tonic-gate /*
757c478bd9Sstevel@tonic-gate * __bt_new --
767c478bd9Sstevel@tonic-gate * Get a new page, preferably from the freelist.
777c478bd9Sstevel@tonic-gate *
787c478bd9Sstevel@tonic-gate * Parameters:
797c478bd9Sstevel@tonic-gate * t: tree
807c478bd9Sstevel@tonic-gate * npg: storage for page number.
817c478bd9Sstevel@tonic-gate *
827c478bd9Sstevel@tonic-gate * Returns:
837c478bd9Sstevel@tonic-gate * Pointer to a page, NULL on error.
847c478bd9Sstevel@tonic-gate */
857c478bd9Sstevel@tonic-gate PAGE *
__bt_new(t,npg)867c478bd9Sstevel@tonic-gate __bt_new(t, npg)
877c478bd9Sstevel@tonic-gate BTREE *t;
887c478bd9Sstevel@tonic-gate db_pgno_t *npg;
897c478bd9Sstevel@tonic-gate {
907c478bd9Sstevel@tonic-gate PAGE *h;
917c478bd9Sstevel@tonic-gate
927c478bd9Sstevel@tonic-gate if (t->bt_free != P_INVALID &&
937c478bd9Sstevel@tonic-gate (h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
947c478bd9Sstevel@tonic-gate *npg = t->bt_free;
957c478bd9Sstevel@tonic-gate t->bt_free = h->nextpg;
967c478bd9Sstevel@tonic-gate F_SET(t, B_METADIRTY);
977c478bd9Sstevel@tonic-gate return (h);
987c478bd9Sstevel@tonic-gate }
997c478bd9Sstevel@tonic-gate return (mpool_new(t->bt_mp, npg, MPOOL_PAGE_NEXT));
1007c478bd9Sstevel@tonic-gate }
101