1/*	$NetBSD: rec_utils.c,v 1.15 2024/05/14 19:00:43 andvar Exp $	*/
2
3/*-
4 * Copyright (c) 1990, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32#if HAVE_NBTOOL_CONFIG_H
33#include "nbtool_config.h"
34#endif
35
36#include <sys/cdefs.h>
37__RCSID("$NetBSD: rec_utils.c,v 1.15 2024/05/14 19:00:43 andvar Exp $");
38
39#include <sys/param.h>
40
41#include <assert.h>
42#include <stdio.h>
43#include <stdlib.h>
44#include <string.h>
45
46#include <db.h>
47#include "recno.h"
48
49/*
50 * __rec_ret --
51 *	Build return data.
52 *
53 * Parameters:
54 *	t:	tree
55 *	e:	key/data pair to be returned
56 *   nrec:	record number
57 *    key:	user's key structure
58 *	data:	user's data structure
59 *
60 * Returns:
61 *	RET_SUCCESS, RET_ERROR.
62 */
63int
64__rec_ret(BTREE *t, EPG *e, recno_t nrec, DBT *key, DBT *data)
65{
66	RLEAF *rl;
67	void *p;
68
69	if (key == NULL)
70		goto dataonly;
71
72	/* We have to copy the key, it's not on the page. */
73	if (sizeof(nrec) > t->bt_rkey.size) {
74		p = realloc(t->bt_rkey.data, sizeof(nrec));
75		if (p == NULL)
76			return (RET_ERROR);
77		t->bt_rkey.data = p;
78		t->bt_rkey.size = sizeof(nrec);
79	}
80	memmove(t->bt_rkey.data, &nrec, sizeof(nrec));
81	key->size = sizeof(nrec);
82	key->data = t->bt_rkey.data;
83
84dataonly:
85	if (data == NULL)
86		return (RET_SUCCESS);
87
88	/*
89	 * We must copy big keys/data to make them contiguous.  Otherwise,
90	 * leave the page pinned and don't copy unless the user specified
91	 * concurrent access.
92	 */
93	rl = GETRLEAF(e->page, e->index);
94	if (rl->flags & P_BIGDATA) {
95		if (__ovfl_get(t, rl->bytes,
96		    &data->size, &t->bt_rdata.data, &t->bt_rdata.size))
97			return (RET_ERROR);
98		data->data = t->bt_rdata.data;
99	} else if (F_ISSET(t, B_DB_LOCK)) {
100		/* Use +1 in case the first record retrieved is 0 length. */
101		if (rl->dsize + 1 > t->bt_rdata.size) {
102			p = realloc(t->bt_rdata.data, rl->dsize + 1);
103			if (p == NULL)
104				return (RET_ERROR);
105			t->bt_rdata.data = p;
106			t->bt_rdata.size = rl->dsize + 1;
107		}
108		memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
109		data->size = rl->dsize;
110		data->data = t->bt_rdata.data;
111	} else {
112		data->size = rl->dsize;
113		data->data = rl->bytes;
114	}
115	return (RET_SUCCESS);
116}
117