mirror of
https://git.rtems.org/rtems-libbsd/
synced 2025-10-19 05:47:23 +08:00
Added userspace db files.
This commit is contained in:
Jennifer Averett
637
freebsd-userspace/lib/libc/db/btree/bt_delete.c
Normal file
637
freebsd-userspace/lib/libc/db/btree/bt_delete.c
Normal file
@@ -0,0 +1,637 @@
|
||||
#include "port_before.h"
|
||||
|
||||
/*-
|
||||
* 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.
|
||||
* 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_delete.c 8.13 (Berkeley) 7/28/94";
|
||||
#endif /* LIBC_SCCS and not lint */
|
||||
#include <sys/cdefs.h>
|
||||
__FBSDID("$FreeBSD$");
|
||||
|
||||
#include <sys/types.h>
|
||||
|
||||
#include <errno.h>
|
||||
#include <stdio.h>
|
||||
#include <string.h>
|
||||
|
||||
#include <db.h>
|
||||
#include "btree.h"
|
||||
|
||||
static int __bt_bdelete(BTREE *, const DBT *);
|
||||
static int __bt_curdel(BTREE *, const DBT *, PAGE *, u_int);
|
||||
static int __bt_pdelete(BTREE *, PAGE *);
|
||||
static int __bt_relink(BTREE *, PAGE *);
|
||||
static int __bt_stkacq(BTREE *, PAGE **, CURSOR *);
|
||||
|
||||
/*
|
||||
* __bt_delete
|
||||
* Delete the item(s) referenced by a key.
|
||||
*
|
||||
* Return RET_SPECIAL if the key is not found.
|
||||
*/
|
||||
int
|
||||
__bt_delete(const DB *dbp, const DBT *key, u_int flags)
|
||||
{
|
||||
BTREE *t;
|
||||
CURSOR *c;
|
||||
PAGE *h;
|
||||
int status;
|
||||
|
||||
t = dbp->internal;
|
||||
|
||||
/* Toss any page pinned across calls. */
|
||||
if (t->bt_pinned != NULL) {
|
||||
mpool_put(t->bt_mp, t->bt_pinned, 0);
|
||||
t->bt_pinned = NULL;
|
||||
}
|
||||
|
||||
/* Check for change to a read-only tree. */
|
||||
if (F_ISSET(t, B_RDONLY)) {
|
||||
errno = EPERM;
|
||||
return (RET_ERROR);
|
||||
}
|
||||
|
||||
switch (flags) {
|
||||
case 0:
|
||||
status = __bt_bdelete(t, key);
|
||||
break;
|
||||
case R_CURSOR:
|
||||
/*
|
||||
* If flags is R_CURSOR, delete the cursor. Must already
|
||||
* have started a scan and not have already deleted it.
|
||||
*/
|
||||
c = &t->bt_cursor;
|
||||
if (F_ISSET(c, CURS_INIT)) {
|
||||
if (F_ISSET(c, CURS_ACQUIRE | CURS_AFTER | CURS_BEFORE))
|
||||
return (RET_SPECIAL);
|
||||
if ((h = mpool_get(t->bt_mp, c->pg.pgno, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
|
||||
/*
|
||||
* If the page is about to be emptied, we'll need to
|
||||
* delete it, which means we have to acquire a stack.
|
||||
*/
|
||||
if (NEXTINDEX(h) == 1)
|
||||
if (__bt_stkacq(t, &h, &t->bt_cursor))
|
||||
return (RET_ERROR);
|
||||
|
||||
status = __bt_dleaf(t, NULL, h, c->pg.index);
|
||||
|
||||
if (NEXTINDEX(h) == 0 && status == RET_SUCCESS) {
|
||||
if (__bt_pdelete(t, h))
|
||||
return (RET_ERROR);
|
||||
} else
|
||||
mpool_put(t->bt_mp,
|
||||
h, status == RET_SUCCESS ? MPOOL_DIRTY : 0);
|
||||
break;
|
||||
}
|
||||
/* FALLTHROUGH */
|
||||
default:
|
||||
errno = EINVAL;
|
||||
return (RET_ERROR);
|
||||
}
|
||||
if (status == RET_SUCCESS)
|
||||
F_SET(t, B_MODIFIED);
|
||||
return (status);
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_stkacq --
|
||||
* Acquire a stack so we can delete a cursor entry.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* hp: pointer to current, pinned PAGE pointer
|
||||
* c: pointer to the cursor
|
||||
*
|
||||
* Returns:
|
||||
* 0 on success, 1 on failure
|
||||
*/
|
||||
static int
|
||||
__bt_stkacq(BTREE *t, PAGE **hp, CURSOR *c)
|
||||
{
|
||||
BINTERNAL *bi;
|
||||
EPG *e;
|
||||
EPGNO *parent;
|
||||
PAGE *h;
|
||||
indx_t idx;
|
||||
pgno_t pgno;
|
||||
recno_t nextpg, prevpg;
|
||||
int exact, level;
|
||||
|
||||
/*
|
||||
* Find the first occurrence of the key in the tree. Toss the
|
||||
* currently locked page so we don't hit an already-locked page.
|
||||
*/
|
||||
h = *hp;
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
if ((e = __bt_search(t, &c->key, &exact)) == NULL)
|
||||
return (1);
|
||||
h = e->page;
|
||||
|
||||
/* See if we got it in one shot. */
|
||||
if (h->pgno == c->pg.pgno)
|
||||
goto ret;
|
||||
|
||||
/*
|
||||
* Move right, looking for the page. At each move we have to move
|
||||
* up the stack until we don't have to move to the next page. If
|
||||
* we have to change pages at an internal level, we have to fix the
|
||||
* stack back up.
|
||||
*/
|
||||
while (h->pgno != c->pg.pgno) {
|
||||
if ((nextpg = h->nextpg) == P_INVALID)
|
||||
break;
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
|
||||
/* Move up the stack. */
|
||||
for (level = 0; (parent = BT_POP(t)) != NULL; ++level) {
|
||||
/* Get the parent page. */
|
||||
if ((h = mpool_get(t->bt_mp, parent->pgno, 0)) == NULL)
|
||||
return (1);
|
||||
|
||||
/* Move to the next index. */
|
||||
if (parent->index != NEXTINDEX(h) - 1) {
|
||||
idx = parent->index + 1;
|
||||
BT_PUSH(t, h->pgno, idx);
|
||||
break;
|
||||
}
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
}
|
||||
|
||||
/* Restore the stack. */
|
||||
while (level--) {
|
||||
/* Push the next level down onto the stack. */
|
||||
bi = GETBINTERNAL(h, idx);
|
||||
pgno = bi->pgno;
|
||||
BT_PUSH(t, pgno, 0);
|
||||
|
||||
/* Lose the currently pinned page. */
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
|
||||
/* Get the next level down. */
|
||||
if ((h = mpool_get(t->bt_mp, pgno, 0)) == NULL)
|
||||
return (1);
|
||||
idx = 0;
|
||||
}
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
if ((h = mpool_get(t->bt_mp, nextpg, 0)) == NULL)
|
||||
return (1);
|
||||
}
|
||||
|
||||
if (h->pgno == c->pg.pgno)
|
||||
goto ret;
|
||||
|
||||
/* Reacquire the original stack. */
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
if ((e = __bt_search(t, &c->key, &exact)) == NULL)
|
||||
return (1);
|
||||
h = e->page;
|
||||
|
||||
/*
|
||||
* Move left, looking for the page. At each move we have to move
|
||||
* up the stack until we don't have to change pages to move to the
|
||||
* next page. If we have to change pages at an internal level, we
|
||||
* have to fix the stack back up.
|
||||
*/
|
||||
while (h->pgno != c->pg.pgno) {
|
||||
if ((prevpg = h->prevpg) == P_INVALID)
|
||||
break;
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
|
||||
/* Move up the stack. */
|
||||
for (level = 0; (parent = BT_POP(t)) != NULL; ++level) {
|
||||
/* Get the parent page. */
|
||||
if ((h = mpool_get(t->bt_mp, parent->pgno, 0)) == NULL)
|
||||
return (1);
|
||||
|
||||
/* Move to the next index. */
|
||||
if (parent->index != 0) {
|
||||
idx = parent->index - 1;
|
||||
BT_PUSH(t, h->pgno, idx);
|
||||
break;
|
||||
}
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
}
|
||||
|
||||
/* Restore the stack. */
|
||||
while (level--) {
|
||||
/* Push the next level down onto the stack. */
|
||||
bi = GETBINTERNAL(h, idx);
|
||||
pgno = bi->pgno;
|
||||
|
||||
/* Lose the currently pinned page. */
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
|
||||
/* Get the next level down. */
|
||||
if ((h = mpool_get(t->bt_mp, pgno, 0)) == NULL)
|
||||
return (1);
|
||||
|
||||
idx = NEXTINDEX(h) - 1;
|
||||
BT_PUSH(t, pgno, idx);
|
||||
}
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
if ((h = mpool_get(t->bt_mp, prevpg, 0)) == NULL)
|
||||
return (1);
|
||||
}
|
||||
|
||||
|
||||
ret: mpool_put(t->bt_mp, h, 0);
|
||||
return ((*hp = mpool_get(t->bt_mp, c->pg.pgno, 0)) == NULL);
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_bdelete --
|
||||
* Delete all key/data pairs matching the specified key.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* key: key to delete
|
||||
*
|
||||
* Returns:
|
||||
* RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
|
||||
*/
|
||||
static int
|
||||
__bt_bdelete(BTREE *t, const DBT *key)
|
||||
{
|
||||
EPG *e;
|
||||
PAGE *h;
|
||||
int deleted, exact, redo;
|
||||
|
||||
deleted = 0;
|
||||
|
||||
/* Find any matching record; __bt_search pins the page. */
|
||||
loop: if ((e = __bt_search(t, key, &exact)) == NULL)
|
||||
return (deleted ? RET_SUCCESS : RET_ERROR);
|
||||
if (!exact) {
|
||||
mpool_put(t->bt_mp, e->page, 0);
|
||||
return (deleted ? RET_SUCCESS : RET_SPECIAL);
|
||||
}
|
||||
|
||||
/*
|
||||
* Delete forward, then delete backward, from the found key. If
|
||||
* there are duplicates and we reach either side of the page, do
|
||||
* the key search again, so that we get them all.
|
||||
*/
|
||||
redo = 0;
|
||||
h = e->page;
|
||||
do {
|
||||
if (__bt_dleaf(t, key, h, e->index)) {
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
return (RET_ERROR);
|
||||
}
|
||||
if (F_ISSET(t, B_NODUPS)) {
|
||||
if (NEXTINDEX(h) == 0) {
|
||||
if (__bt_pdelete(t, h))
|
||||
return (RET_ERROR);
|
||||
} else
|
||||
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
deleted = 1;
|
||||
} while (e->index < NEXTINDEX(h) && __bt_cmp(t, key, e) == 0);
|
||||
|
||||
/* Check for right-hand edge of the page. */
|
||||
if (e->index == NEXTINDEX(h))
|
||||
redo = 1;
|
||||
|
||||
/* Delete from the key to the beginning of the page. */
|
||||
while (e->index-- > 0) {
|
||||
if (__bt_cmp(t, key, e) != 0)
|
||||
break;
|
||||
if (__bt_dleaf(t, key, h, e->index) == RET_ERROR) {
|
||||
mpool_put(t->bt_mp, h, 0);
|
||||
return (RET_ERROR);
|
||||
}
|
||||
if (e->index == 0)
|
||||
redo = 1;
|
||||
}
|
||||
|
||||
/* Check for an empty page. */
|
||||
if (NEXTINDEX(h) == 0) {
|
||||
if (__bt_pdelete(t, h))
|
||||
return (RET_ERROR);
|
||||
goto loop;
|
||||
}
|
||||
|
||||
/* Put the page. */
|
||||
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
||||
|
||||
if (redo)
|
||||
goto loop;
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_pdelete --
|
||||
* Delete a single page from the tree.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* h: leaf page
|
||||
*
|
||||
* Returns:
|
||||
* RET_SUCCESS, RET_ERROR.
|
||||
*
|
||||
* Side-effects:
|
||||
* mpool_put's the page
|
||||
*/
|
||||
static int
|
||||
__bt_pdelete(BTREE *t, PAGE *h)
|
||||
{
|
||||
BINTERNAL *bi;
|
||||
PAGE *pg;
|
||||
EPGNO *parent;
|
||||
indx_t cnt, idx, *ip, offset;
|
||||
u_int32_t nksize;
|
||||
char *from;
|
||||
|
||||
/*
|
||||
* Walk the parent page stack -- a LIFO stack of the pages that were
|
||||
* traversed when we searched for the page where the delete occurred.
|
||||
* Each stack entry is a page number and a page index offset. The
|
||||
* offset is for the page traversed on the search. We've just deleted
|
||||
* a page, so we have to delete the key from the parent page.
|
||||
*
|
||||
* If the delete from the parent page makes it empty, this process may
|
||||
* continue all the way up the tree. We stop if we reach the root page
|
||||
* (which is never deleted, it's just not worth the effort) or if the
|
||||
* delete does not empty the page.
|
||||
*/
|
||||
while ((parent = BT_POP(t)) != NULL) {
|
||||
/* Get the parent page. */
|
||||
if ((pg = mpool_get(t->bt_mp, parent->pgno, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
|
||||
idx = parent->index;
|
||||
bi = GETBINTERNAL(pg, idx);
|
||||
|
||||
/* Free any overflow pages. */
|
||||
if (bi->flags & P_BIGKEY &&
|
||||
__ovfl_delete(t, bi->bytes) == RET_ERROR) {
|
||||
mpool_put(t->bt_mp, pg, 0);
|
||||
return (RET_ERROR);
|
||||
}
|
||||
|
||||
/*
|
||||
* Free the parent if it has only the one key and it's not the
|
||||
* root page. If it's the rootpage, turn it back into an empty
|
||||
* leaf page.
|
||||
*/
|
||||
if (NEXTINDEX(pg) == 1) {
|
||||
if (pg->pgno == P_ROOT) {
|
||||
pg->lower = BTDATAOFF;
|
||||
pg->upper = t->bt_psize;
|
||||
pg->flags = P_BLEAF;
|
||||
} else {
|
||||
if (__bt_relink(t, pg) || __bt_free(t, pg))
|
||||
return (RET_ERROR);
|
||||
continue;
|
||||
}
|
||||
} else {
|
||||
/* Pack remaining key items at the end of the page. */
|
||||
nksize = NBINTERNAL(bi->ksize);
|
||||
from = (char *)pg + pg->upper;
|
||||
memmove(from + nksize, from, (char *)bi - from);
|
||||
pg->upper += nksize;
|
||||
|
||||
/* Adjust indices' offsets, shift the indices down. */
|
||||
offset = pg->linp[idx];
|
||||
for (cnt = idx, ip = &pg->linp[0]; cnt--; ++ip)
|
||||
if (ip[0] < offset)
|
||||
ip[0] += nksize;
|
||||
for (cnt = NEXTINDEX(pg) - idx; --cnt; ++ip)
|
||||
ip[0] = ip[1] < offset ? ip[1] + nksize : ip[1];
|
||||
pg->lower -= sizeof(indx_t);
|
||||
}
|
||||
|
||||
mpool_put(t->bt_mp, pg, MPOOL_DIRTY);
|
||||
break;
|
||||
}
|
||||
|
||||
/* Free the leaf page, as long as it wasn't the root. */
|
||||
if (h->pgno == P_ROOT) {
|
||||
mpool_put(t->bt_mp, h, MPOOL_DIRTY);
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
return (__bt_relink(t, h) || __bt_free(t, h));
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_dleaf --
|
||||
* Delete a single record from a leaf page.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* key: referenced key
|
||||
* h: page
|
||||
* idx: index on page to delete
|
||||
*
|
||||
* Returns:
|
||||
* RET_SUCCESS, RET_ERROR.
|
||||
*/
|
||||
int
|
||||
__bt_dleaf(BTREE *t, const DBT *key, PAGE *h, u_int idx)
|
||||
{
|
||||
BLEAF *bl;
|
||||
indx_t cnt, *ip, offset;
|
||||
u_int32_t nbytes;
|
||||
void *to;
|
||||
char *from;
|
||||
|
||||
/* If this record is referenced by the cursor, delete the cursor. */
|
||||
if (F_ISSET(&t->bt_cursor, CURS_INIT) &&
|
||||
!F_ISSET(&t->bt_cursor, CURS_ACQUIRE) &&
|
||||
t->bt_cursor.pg.pgno == h->pgno && t->bt_cursor.pg.index == idx &&
|
||||
__bt_curdel(t, key, h, idx))
|
||||
return (RET_ERROR);
|
||||
|
||||
/* If the entry uses overflow pages, make them available for reuse. */
|
||||
to = bl = GETBLEAF(h, idx);
|
||||
if (bl->flags & P_BIGKEY && __ovfl_delete(t, bl->bytes) == RET_ERROR)
|
||||
return (RET_ERROR);
|
||||
if (bl->flags & P_BIGDATA &&
|
||||
__ovfl_delete(t, bl->bytes + bl->ksize) == RET_ERROR)
|
||||
return (RET_ERROR);
|
||||
|
||||
/* Pack the remaining key/data items at the end of the page. */
|
||||
nbytes = NBLEAF(bl);
|
||||
from = (char *)h + h->upper;
|
||||
memmove(from + nbytes, from, (char *)to - from);
|
||||
h->upper += nbytes;
|
||||
|
||||
/* Adjust the indices' offsets, shift the indices down. */
|
||||
offset = h->linp[idx];
|
||||
for (cnt = idx, ip = &h->linp[0]; cnt--; ++ip)
|
||||
if (ip[0] < offset)
|
||||
ip[0] += nbytes;
|
||||
for (cnt = NEXTINDEX(h) - idx; --cnt; ++ip)
|
||||
ip[0] = ip[1] < offset ? ip[1] + nbytes : ip[1];
|
||||
h->lower -= sizeof(indx_t);
|
||||
|
||||
/* If the cursor is on this page, adjust it as necessary. */
|
||||
if (F_ISSET(&t->bt_cursor, CURS_INIT) &&
|
||||
!F_ISSET(&t->bt_cursor, CURS_ACQUIRE) &&
|
||||
t->bt_cursor.pg.pgno == h->pgno && t->bt_cursor.pg.index > idx)
|
||||
--t->bt_cursor.pg.index;
|
||||
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_curdel --
|
||||
* Delete the cursor.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* key: referenced key (or NULL)
|
||||
* h: page
|
||||
* idx: index on page to delete
|
||||
*
|
||||
* Returns:
|
||||
* RET_SUCCESS, RET_ERROR.
|
||||
*/
|
||||
static int
|
||||
__bt_curdel(BTREE *t, const DBT *key, PAGE *h, u_int idx)
|
||||
{
|
||||
CURSOR *c;
|
||||
EPG e;
|
||||
PAGE *pg;
|
||||
int curcopy, status;
|
||||
|
||||
/*
|
||||
* If there are duplicates, move forward or backward to one.
|
||||
* Otherwise, copy the key into the cursor area.
|
||||
*/
|
||||
c = &t->bt_cursor;
|
||||
F_CLR(c, CURS_AFTER | CURS_BEFORE | CURS_ACQUIRE);
|
||||
|
||||
curcopy = 0;
|
||||
if (!F_ISSET(t, B_NODUPS)) {
|
||||
/*
|
||||
* We're going to have to do comparisons. If we weren't
|
||||
* provided a copy of the key, i.e. the user is deleting
|
||||
* the current cursor position, get one.
|
||||
*/
|
||||
if (key == NULL) {
|
||||
e.page = h;
|
||||
e.index = idx;
|
||||
if ((status = __bt_ret(t, &e,
|
||||
&c->key, &c->key, NULL, NULL, 1)) != RET_SUCCESS)
|
||||
return (status);
|
||||
curcopy = 1;
|
||||
key = &c->key;
|
||||
}
|
||||
/* Check previous key, if not at the beginning of the page. */
|
||||
if (idx > 0) {
|
||||
e.page = h;
|
||||
e.index = idx - 1;
|
||||
if (__bt_cmp(t, key, &e) == 0) {
|
||||
F_SET(c, CURS_BEFORE);
|
||||
goto dup2;
|
||||
}
|
||||
}
|
||||
/* Check next key, if not at the end of the page. */
|
||||
if (idx < NEXTINDEX(h) - 1) {
|
||||
e.page = h;
|
||||
e.index = idx + 1;
|
||||
if (__bt_cmp(t, key, &e) == 0) {
|
||||
F_SET(c, CURS_AFTER);
|
||||
goto dup2;
|
||||
}
|
||||
}
|
||||
/* Check previous key if at the beginning of the page. */
|
||||
if (idx == 0 && h->prevpg != P_INVALID) {
|
||||
if ((pg = mpool_get(t->bt_mp, h->prevpg, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
e.page = pg;
|
||||
e.index = NEXTINDEX(pg) - 1;
|
||||
if (__bt_cmp(t, key, &e) == 0) {
|
||||
F_SET(c, CURS_BEFORE);
|
||||
goto dup1;
|
||||
}
|
||||
mpool_put(t->bt_mp, pg, 0);
|
||||
}
|
||||
/* Check next key if at the end of the page. */
|
||||
if (idx == NEXTINDEX(h) - 1 && h->nextpg != P_INVALID) {
|
||||
if ((pg = mpool_get(t->bt_mp, h->nextpg, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
e.page = pg;
|
||||
e.index = 0;
|
||||
if (__bt_cmp(t, key, &e) == 0) {
|
||||
F_SET(c, CURS_AFTER);
|
||||
dup1: mpool_put(t->bt_mp, pg, 0);
|
||||
dup2: c->pg.pgno = e.page->pgno;
|
||||
c->pg.index = e.index;
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
mpool_put(t->bt_mp, pg, 0);
|
||||
}
|
||||
}
|
||||
e.page = h;
|
||||
e.index = idx;
|
||||
if (curcopy || (status =
|
||||
__bt_ret(t, &e, &c->key, &c->key, NULL, NULL, 1)) == RET_SUCCESS) {
|
||||
F_SET(c, CURS_ACQUIRE);
|
||||
return (RET_SUCCESS);
|
||||
}
|
||||
return (status);
|
||||
}
|
||||
|
||||
/*
|
||||
* __bt_relink --
|
||||
* Link around a deleted page.
|
||||
*
|
||||
* Parameters:
|
||||
* t: tree
|
||||
* h: page to be deleted
|
||||
*/
|
||||
static int
|
||||
__bt_relink(BTREE *t, PAGE *h)
|
||||
{
|
||||
PAGE *pg;
|
||||
|
||||
if (h->nextpg != P_INVALID) {
|
||||
if ((pg = mpool_get(t->bt_mp, h->nextpg, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
pg->prevpg = h->prevpg;
|
||||
mpool_put(t->bt_mp, pg, MPOOL_DIRTY);
|
||||
}
|
||||
if (h->prevpg != P_INVALID) {
|
||||
if ((pg = mpool_get(t->bt_mp, h->prevpg, 0)) == NULL)
|
||||
return (RET_ERROR);
|
||||
pg->nextpg = h->nextpg;
|
||||
mpool_put(t->bt_mp, pg, MPOOL_DIRTY);
|
||||
}
|
||||
return (0);
|
||||
}
|
||||
Reference in New Issue
Block a user