[apple/libc.git] / db / btree / FreeBSD / bt_page.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: src/lib/libc/db/btree/bt_page.c,v 1.5 2009/03/02 23:47:18 delphij Exp $");

#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));
}
Commit	Line	Data
9385eb3d A	1	/*-
9385eb3d A	2	* Copyright (c) 1990, 1993, 1994
e9ce8d39 A	3	* The Regents of the University of California. All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions
	7	* are met:
	8	* 1. Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* 2. Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
e9ce8d39 A	13	* 4. Neither the name of the University nor the names of its contributors
	14	* may be used to endorse or promote products derived from this software
	15	* without specific prior written permission.
	16	*
	17	* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
	18	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	19	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	20	* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
	21	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	22	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	23	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	24	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	25	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	26	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	27	* SUCH DAMAGE.
	28	*/
	29
9385eb3d A	30	#if defined(LIBC_SCCS) && !defined(lint)
	31	static char sccsid[] = "@(#)bt_page.c 8.3 (Berkeley) 7/14/94";
	32	#endif /* LIBC_SCCS and not lint */
	33	#include <sys/cdefs.h>
1f2f436a	34	__FBSDID("$FreeBSD: src/lib/libc/db/btree/bt_page.c,v 1.5 2009/03/02 23:47:18 delphij Exp $");
e9ce8d39 A	35
	36	#include <sys/types.h>
	37
	38	#include <stdio.h>
	39
	40	#include <db.h>
	41	#include "btree.h"
	42
	43	/*
9385eb3d A	44	* __bt_free --
9385eb3d A	45	* Put a page on the freelist.
e9ce8d39 A	46	*
	47	* Parameters:
	48	* t: tree
	49	* h: page to free
	50	*
	51	* Returns:
	52	* RET_ERROR, RET_SUCCESS
9385eb3d A	53	*
	54	* Side-effect:
	55	* mpool_put's the page.
e9ce8d39 A	56	*/
e9ce8d39 A	57	int
1f2f436a	58	__bt_free(BTREE t, PAGE h)
e9ce8d39	59	{
9385eb3d	60	/* Insert the page at the head of the free list. */
e9ce8d39 A	61	h->prevpg = P_INVALID;
	62	h->nextpg = t->bt_free;
	63	t->bt_free = h->pgno;
9385eb3d	64	F_SET(t, B_METADIRTY);
e9ce8d39 A	65
	66	/* Make sure the page gets written back. */
	67	return (mpool_put(t->bt_mp, h, MPOOL_DIRTY));
	68	}
	69
	70	/*
9385eb3d A	71	* __bt_new --
9385eb3d A	72	* Get a new page, preferably from the freelist.
e9ce8d39 A	73	*
	74	* Parameters:
	75	* t: tree
	76	* npg: storage for page number.
	77	*
	78	* Returns:
	79	* Pointer to a page, NULL on error.
	80	*/
	81	PAGE *
1f2f436a	82	__bt_new(BTREE t, pgno_t npg)
e9ce8d39 A	83	{
	84	PAGE *h;
	85
	86	if (t->bt_free != P_INVALID &&
	87	(h = mpool_get(t->bt_mp, t->bt_free, 0)) != NULL) {
9385eb3d A	88	*npg = t->bt_free;
	89	t->bt_free = h->nextpg;
	90	F_SET(t, B_METADIRTY);
	91	return (h);
e9ce8d39 A	92	}
	93	return (mpool_new(t->bt_mp, npg));
	94	}