This patch imports the unmodified current version of NetBSD libc. The NetBSD includes are in /nbsd_include, while the libc code itself is split between lib/nbsd_libc and common/lib/libc.
232 lines
5.9 KiB
C
232 lines
5.9 KiB
C
/* $NetBSD: bt_overflow.c,v 1.16 2008/09/11 12:58:00 joerg Exp $ */
|
|
|
|
/*-
|
|
* Copyright (c) 1990, 1993, 1994
|
|
* The Regents of the University of California. All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to Berkeley by
|
|
* Mike Olson.
|
|
*
|
|
* 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 HAVE_NBTOOL_CONFIG_H
|
|
#include "nbtool_config.h"
|
|
#endif
|
|
|
|
#include <sys/cdefs.h>
|
|
__RCSID("$NetBSD: bt_overflow.c,v 1.16 2008/09/11 12:58:00 joerg Exp $");
|
|
|
|
#include "namespace.h"
|
|
#include <sys/param.h>
|
|
|
|
#include <assert.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
|
|
#include <db.h>
|
|
#include "btree.h"
|
|
|
|
/*
|
|
* Big key/data code.
|
|
*
|
|
* Big key and data entries are stored on linked lists of pages. The initial
|
|
* reference is byte string stored with the key or data and is the page number
|
|
* and size. The actual record is stored in a chain of pages linked by the
|
|
* nextpg field of the PAGE header.
|
|
*
|
|
* The first page of the chain has a special property. If the record is used
|
|
* by an internal page, it cannot be deleted and the P_PRESERVE bit will be set
|
|
* in the header.
|
|
*
|
|
* XXX
|
|
* A single DBT is written to each chain, so a lot of space on the last page
|
|
* is wasted. This is a fairly major bug for some data sets.
|
|
*/
|
|
|
|
/*
|
|
* __OVFL_GET -- Get an overflow key/data item.
|
|
*
|
|
* Parameters:
|
|
* t: tree
|
|
* p: pointer to { pgno_t, uint32_t }
|
|
* buf: storage address
|
|
* bufsz: storage size
|
|
*
|
|
* Returns:
|
|
* RET_ERROR, RET_SUCCESS
|
|
*/
|
|
int
|
|
__ovfl_get(BTREE *t, void *p, size_t *ssz, void **buf, size_t *bufsz)
|
|
{
|
|
PAGE *h;
|
|
pgno_t pg;
|
|
uint32_t sz, nb, plen;
|
|
size_t temp;
|
|
|
|
memmove(&pg, p, sizeof(pgno_t));
|
|
memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(uint32_t));
|
|
*ssz = sz;
|
|
|
|
#ifdef DEBUG
|
|
if (pg == P_INVALID || sz == 0)
|
|
abort();
|
|
#endif
|
|
/* Make the buffer bigger as necessary. */
|
|
if (*bufsz < sz) {
|
|
*buf = (char *)(*buf == NULL ? malloc(sz) : realloc(*buf, sz));
|
|
if (*buf == NULL)
|
|
return (RET_ERROR);
|
|
*bufsz = sz;
|
|
}
|
|
|
|
/*
|
|
* Step through the linked list of pages, copying the data on each one
|
|
* into the buffer. Never copy more than the data's length.
|
|
*/
|
|
temp = t->bt_psize - BTDATAOFF;
|
|
_DBFIT(temp, uint32_t);
|
|
plen = (uint32_t)temp;
|
|
for (p = *buf;; p = (char *)p + nb, pg = h->nextpg) {
|
|
if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
|
|
return (RET_ERROR);
|
|
|
|
nb = MIN(sz, plen);
|
|
memmove(p, (char *)(void *)h + BTDATAOFF, nb);
|
|
mpool_put(t->bt_mp, h, 0);
|
|
|
|
if ((sz -= nb) == 0)
|
|
break;
|
|
}
|
|
return (RET_SUCCESS);
|
|
}
|
|
|
|
/*
|
|
* __OVFL_PUT -- Store an overflow key/data item.
|
|
*
|
|
* Parameters:
|
|
* t: tree
|
|
* data: DBT to store
|
|
* pgno: storage page number
|
|
*
|
|
* Returns:
|
|
* RET_ERROR, RET_SUCCESS
|
|
*/
|
|
int
|
|
__ovfl_put(BTREE *t, const DBT *dbt, pgno_t *pg)
|
|
{
|
|
PAGE *h, *last;
|
|
void *p;
|
|
pgno_t npg;
|
|
uint32_t sz, nb, plen;
|
|
size_t temp;
|
|
|
|
/*
|
|
* Allocate pages and copy the key/data record into them. Store the
|
|
* number of the first page in the chain.
|
|
*/
|
|
temp = t->bt_psize - BTDATAOFF;
|
|
_DBFIT(temp, uint32_t);
|
|
plen = (uint32_t)temp;
|
|
last = NULL;
|
|
p = dbt->data;
|
|
temp = dbt->size;
|
|
_DBFIT(temp, uint32_t);
|
|
sz = temp;
|
|
for (;; p = (char *)p + plen, last = h) {
|
|
if ((h = __bt_new(t, &npg)) == NULL)
|
|
return (RET_ERROR);
|
|
|
|
h->pgno = npg;
|
|
h->nextpg = h->prevpg = P_INVALID;
|
|
h->flags = P_OVERFLOW;
|
|
h->lower = h->upper = 0;
|
|
|
|
nb = MIN(sz, plen);
|
|
(void)memmove((char *)(void *)h + BTDATAOFF, p, (size_t)nb);
|
|
|
|
if (last) {
|
|
last->nextpg = h->pgno;
|
|
mpool_put(t->bt_mp, last, MPOOL_DIRTY);
|
|
} else
|
|
*pg = h->pgno;
|
|
|
|
if ((sz -= nb) == 0) {
|
|
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
|
break;
|
|
}
|
|
}
|
|
return (RET_SUCCESS);
|
|
}
|
|
|
|
/*
|
|
* __OVFL_DELETE -- Delete an overflow chain.
|
|
*
|
|
* Parameters:
|
|
* t: tree
|
|
* p: pointer to { pgno_t, uint32_t }
|
|
*
|
|
* Returns:
|
|
* RET_ERROR, RET_SUCCESS
|
|
*/
|
|
int
|
|
__ovfl_delete(BTREE *t, void *p)
|
|
{
|
|
PAGE *h;
|
|
pgno_t pg;
|
|
uint32_t sz, plen;
|
|
size_t temp;
|
|
|
|
(void)memmove(&pg, p, sizeof(pgno_t));
|
|
(void)memmove(&sz, (char *)p + sizeof(pgno_t), sizeof(uint32_t));
|
|
|
|
#ifdef DEBUG
|
|
if (pg == P_INVALID || sz == 0)
|
|
abort();
|
|
#endif
|
|
if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
|
|
return (RET_ERROR);
|
|
|
|
/* Don't delete chains used by internal pages. */
|
|
if (h->flags & P_PRESERVE) {
|
|
mpool_put(t->bt_mp, h, 0);
|
|
return (RET_SUCCESS);
|
|
}
|
|
|
|
/* Step through the chain, calling the free routine for each page. */
|
|
temp = t->bt_psize - BTDATAOFF;
|
|
_DBFIT(temp, uint32_t);
|
|
plen = (uint32_t)temp;
|
|
for (;; sz -= plen) {
|
|
pg = h->nextpg;
|
|
__bt_free(t, h);
|
|
if (sz <= plen)
|
|
break;
|
|
if ((h = mpool_get(t->bt_mp, pg, 0)) == NULL)
|
|
return (RET_ERROR);
|
|
}
|
|
return (RET_SUCCESS);
|
|
}
|