GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/db/recno/rec_delete.c Lines: 0 47 0.0 %
Date: 2017-11-13 Branches: 0 31 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: rec_delete.c,v 1.10 2005/08/05 13:03:00 espie Exp $	*/
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/*-
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 * Copyright (c) 1990, 1993, 1994
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Mike Olson.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <sys/types.h>
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#include <errno.h>
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#include <stdio.h>
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#include <string.h>
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#include <db.h>
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#include "recno.h"
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static int rec_rdelete(BTREE *, recno_t);
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/*
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 * __REC_DELETE -- Delete the item(s) referenced by a key.
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 *
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 * Parameters:
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 *	dbp:	pointer to access method
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 *	key:	key to delete
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 *	flags:	R_CURSOR if deleting what the cursor references
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 *
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 * Returns:
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 *	RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
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 */
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int
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__rec_delete(const DB *dbp, const DBT *key, u_int flags)
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{
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	BTREE *t;
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	recno_t nrec;
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	int status;
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	t = dbp->internal;
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	/* Toss any page pinned across calls. */
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	if (t->bt_pinned != NULL) {
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		mpool_put(t->bt_mp, t->bt_pinned, 0);
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		t->bt_pinned = NULL;
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	}
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	switch(flags) {
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	case 0:
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		if ((nrec = *(recno_t *)key->data) == 0)
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			goto einval;
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		if (nrec > t->bt_nrecs)
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			return (RET_SPECIAL);
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		--nrec;
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		status = rec_rdelete(t, nrec);
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		break;
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	case R_CURSOR:
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		if (!F_ISSET(&t->bt_cursor, CURS_INIT))
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			goto einval;
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		if (t->bt_nrecs == 0)
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			return (RET_SPECIAL);
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		status = rec_rdelete(t, t->bt_cursor.rcursor - 1);
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		if (status == RET_SUCCESS)
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			--t->bt_cursor.rcursor;
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		break;
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	default:
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einval:		errno = EINVAL;
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		return (RET_ERROR);
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	}
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	if (status == RET_SUCCESS)
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		F_SET(t, B_MODIFIED | R_MODIFIED);
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	return (status);
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}
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/*
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 * REC_RDELETE -- Delete the data matching the specified key.
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 *
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 * Parameters:
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 *	tree:	tree
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 *	nrec:	record to delete
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 *
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 * Returns:
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 *	RET_ERROR, RET_SUCCESS and RET_SPECIAL if the key not found.
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 */
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static int
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rec_rdelete(BTREE *t, recno_t nrec)
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{
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	EPG *e;
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	PAGE *h;
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	int status;
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	/* Find the record; __rec_search pins the page. */
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	if ((e = __rec_search(t, nrec, SDELETE)) == NULL)
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		return (RET_ERROR);
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	/* Delete the record. */
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	h = e->page;
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	status = __rec_dleaf(t, h, e->index);
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	if (status != RET_SUCCESS) {
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		mpool_put(t->bt_mp, h, 0);
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		return (status);
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	}
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	mpool_put(t->bt_mp, h, MPOOL_DIRTY);
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	return (RET_SUCCESS);
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}
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/*
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 * __REC_DLEAF -- Delete a single record from a recno leaf page.
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 *
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 * Parameters:
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 *	t:	tree
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 *	idx:	index on current page to delete
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 *
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 * Returns:
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 *	RET_SUCCESS, RET_ERROR.
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 */
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int
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__rec_dleaf(BTREE *t, PAGE *h, u_int32_t idx)
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{
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	RLEAF *rl;
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	indx_t *ip, cnt, offset;
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	u_int32_t nbytes;
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	char *from;
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	void *to;
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	/*
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	 * Delete a record from a recno leaf page.  Internal records are never
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	 * deleted from internal pages, regardless of the records that caused
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	 * them to be added being deleted.  Pages made empty by deletion are
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	 * not reclaimed.  They are, however, made available for reuse.
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	 *
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	 * Pack the remaining entries at the end of the page, shift the indices
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	 * down, overwriting the deleted record and its index.  If the record
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	 * uses overflow pages, make them available for reuse.
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	 */
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	to = rl = GETRLEAF(h, idx);
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	if (rl->flags & P_BIGDATA && __ovfl_delete(t, rl->bytes) == RET_ERROR)
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		return (RET_ERROR);
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	nbytes = NRLEAF(rl);
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	/*
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	 * Compress the key/data pairs.  Compress and adjust the [BR]LEAF
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	 * offsets.  Reset the headers.
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	 */
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	from = (char *)h + h->upper;
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	memmove(from + nbytes, from, (char *)to - from);
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	h->upper += nbytes;
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	offset = h->linp[idx];
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	for (cnt = &h->linp[idx] - (ip = &h->linp[0]); cnt--; ++ip)
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		if (ip[0] < offset)
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			ip[0] += nbytes;
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	for (cnt = &h->linp[NEXTINDEX(h)] - ip; --cnt; ++ip)
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		ip[0] = ip[1] < offset ? ip[1] + nbytes : ip[1];
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	h->lower -= sizeof(indx_t);
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	--t->bt_nrecs;
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	return (RET_SUCCESS);
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}