1 /* $OpenBSD: rec_utils.c,v 1.10 2022/12/27 17:10:06 jmc Exp $ */
2 /*-
3 * Copyright (c) 1990, 1993, 1994
4 * The Regents of the University of California. All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * 3. Neither the name of the University nor the names of its contributors
15 * may be used to endorse or promote products derived from this software
16 * without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34
35 #include <db.h>
36 #include "recno.h"
37
38 /*
39 * __rec_ret --
40 * Build return data.
41 *
42 * Parameters:
43 * t: tree
44 * e: key/data pair to be returned
45 * nrec: record number
46 * key: user's key structure
47 * data: user's data structure
48 *
49 * Returns:
50 * RET_SUCCESS, RET_ERROR.
51 */
52 int
__rec_ret(BTREE * t,EPG * e,recno_t nrec,DBT * key,DBT * data)53 __rec_ret(BTREE *t, EPG *e, recno_t nrec, DBT *key, DBT *data)
54 {
55 RLEAF *rl;
56 void *p;
57
58 if (key == NULL)
59 goto dataonly;
60
61 /* We have to copy the key, it's not on the page. */
62 if (sizeof(recno_t) > t->bt_rkey.size) {
63 p = realloc(t->bt_rkey.data, sizeof(recno_t));
64 if (p == NULL)
65 return (RET_ERROR);
66 t->bt_rkey.data = p;
67 t->bt_rkey.size = sizeof(recno_t);
68 }
69 memmove(t->bt_rkey.data, &nrec, sizeof(recno_t));
70 key->size = sizeof(recno_t);
71 key->data = t->bt_rkey.data;
72
73 dataonly:
74 if (data == NULL)
75 return (RET_SUCCESS);
76
77 /*
78 * We must copy big keys/data to make them contiguous. Otherwise,
79 * leave the page pinned and don't copy unless the user specified
80 * concurrent access.
81 */
82 rl = GETRLEAF(e->page, e->index);
83 if (rl->flags & P_BIGDATA) {
84 if (__ovfl_get(t, rl->bytes,
85 &data->size, &t->bt_rdata.data, &t->bt_rdata.size))
86 return (RET_ERROR);
87 data->data = t->bt_rdata.data;
88 } else if (F_ISSET(t, B_DB_LOCK)) {
89 /* Use +1 in case the first record retrieved is 0 length. */
90 if (rl->dsize + 1 > t->bt_rdata.size) {
91 p = realloc(t->bt_rdata.data, rl->dsize + 1);
92 if (p == NULL)
93 return (RET_ERROR);
94 t->bt_rdata.data = p;
95 t->bt_rdata.size = rl->dsize + 1;
96 }
97 memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
98 data->size = rl->dsize;
99 data->data = t->bt_rdata.data;
100 } else {
101 data->size = rl->dsize;
102 data->data = rl->bytes;
103 }
104 return (RET_SUCCESS);
105 }
106