+++ /dev/null
-/*-
- * 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. All advertising materials mentioning features or use of this software
- * must display the following acknowledgement:
- * This product includes software developed by the University of
- * California, Berkeley and its contributors.
- * 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[] = "@(#)rec_delete.c 8.7 (Berkeley) 7/14/94";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/db/recno/rec_delete.c,v 1.2 2002/03/21 22:46:28 obrien Exp $");
-
-#include <sys/types.h>
-
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-
-#include <db.h>
-#include "recno.h"
-
-static int rec_rdelete(BTREE *, recno_t);
-
-/*
- * __REC_DELETE -- Delete the item(s) referenced by a key.
- *
- * Parameters:
- * dbp: pointer to access method
- * key: key to delete
- * flags: R_CURSOR if deleting what the cursor references
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
- */
-int
-__rec_delete(dbp, key, flags)
- const DB *dbp;
- const DBT *key;
- u_int flags;
-{
- BTREE *t;
- recno_t nrec;
- 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;
- }
-
- switch(flags) {
- case 0:
- if ((nrec = *(recno_t *)key->data) == 0)
- goto einval;
- if (nrec > t->bt_nrecs)
- return (RET_SPECIAL);
- --nrec;
- status = rec_rdelete(t, nrec);
- break;
- case R_CURSOR:
- if (!F_ISSET(&t->bt_cursor, CURS_INIT))
- goto einval;
- if (t->bt_nrecs == 0)
- return (RET_SPECIAL);
- status = rec_rdelete(t, t->bt_cursor.rcursor - 1);
- if (status == RET_SUCCESS)
- --t->bt_cursor.rcursor;
- break;
- default:
-einval: errno = EINVAL;
- return (RET_ERROR);
- }
-
- if (status == RET_SUCCESS)
- F_SET(t, B_MODIFIED | R_MODIFIED);
- return (status);
-}
-
-/*
- * REC_RDELETE -- Delete the data matching the specified key.
- *
- * Parameters:
- * tree: tree
- * nrec: record to delete
- *
- * Returns:
- * RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
- */
-static int
-rec_rdelete(t, nrec)
- BTREE *t;
- recno_t nrec;
-{
- EPG *e;
- PAGE *h;
- int status;
-
- /* Find the record; __rec_search pins the page. */
- if ((e = __rec_search(t, nrec, SDELETE)) == NULL)
- return (RET_ERROR);
-
- /* Delete the record. */
- h = e->page;
- status = __rec_dleaf(t, h, e->index);
- if (status != RET_SUCCESS) {
- mpool_put(t->bt_mp, h, 0);
- return (status);
- }
- mpool_put(t->bt_mp, h, MPOOL_DIRTY);
- return (RET_SUCCESS);
-}
-
-/*
- * __REC_DLEAF -- Delete a single record from a recno leaf page.
- *
- * Parameters:
- * t: tree
- * index: index on current page to delete
- *
- * Returns:
- * RET_SUCCESS, RET_ERROR.
- */
-int
-__rec_dleaf(t, h, index)
- BTREE *t;
- PAGE *h;
- u_int32_t index;
-{
- RLEAF *rl;
- indx_t *ip, cnt, offset;
- u_int32_t nbytes;
- char *from;
- void *to;
-
- /*
- * Delete a record from a recno leaf page. Internal records are never
- * deleted from internal pages, regardless of the records that caused
- * them to be added being deleted. Pages made empty by deletion are
- * not reclaimed. They are, however, made available for reuse.
- *
- * Pack the remaining entries at the end of the page, shift the indices
- * down, overwriting the deleted record and its index. If the record
- * uses overflow pages, make them available for reuse.
- */
- to = rl = GETRLEAF(h, index);
- if (rl->flags & P_BIGDATA && __ovfl_delete(t, rl->bytes) == RET_ERROR)
- return (RET_ERROR);
- nbytes = NRLEAF(rl);
-
- /*
- * Compress the key/data pairs. Compress and adjust the [BR]LEAF
- * offsets. Reset the headers.
- */
- from = (char *)h + h->upper;
- memmove(from + nbytes, from, (char *)to - from);
- h->upper += nbytes;
-
- offset = h->linp[index];
- for (cnt = &h->linp[index] - (ip = &h->linp[0]); cnt--; ++ip)
- if (ip[0] < offset)
- ip[0] += nbytes;
- for (cnt = &h->linp[NEXTINDEX(h)] - ip; --cnt; ++ip)
- ip[0] = ip[1] < offset ? ip[1] + nbytes : ip[1];
- h->lower -= sizeof(indx_t);
- --t->bt_nrecs;
- return (RET_SUCCESS);
-}
projects / apple / libc.git / blobdiff