xref: /netbsd-src/lib/libc/db/recno/rec_utils.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: rec_utils.c,v 1.11 2007/02/03 23:46:09 christos 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 #if defined(LIBC_SCCS) && !defined(lint)
38 #if 0
39 static char sccsid[] = "@(#)rec_utils.c	8.6 (Berkeley) 7/16/94";
40 #else
41 __RCSID("$NetBSD: rec_utils.c,v 1.11 2007/02/03 23:46:09 christos Exp $");
42 #endif
43 #endif /* LIBC_SCCS and not lint */
44 
45 #include <sys/param.h>
46 
47 #include <assert.h>
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 
52 #include <db.h>
53 #include "recno.h"
54 
55 /*
56  * __rec_ret --
57  *	Build return data.
58  *
59  * Parameters:
60  *	t:	tree
61  *	e:	key/data pair to be returned
62  *   nrec:	record number
63  *    key:	user's key structure
64  *	data:	user's data structure
65  *
66  * Returns:
67  *	RET_SUCCESS, RET_ERROR.
68  */
69 int
70 __rec_ret(BTREE *t, EPG *e, recno_t nrec, DBT *key, DBT *data)
71 {
72 	RLEAF *rl;
73 	void *p;
74 
75 	if (key == NULL)
76 		goto dataonly;
77 
78 	/* We have to copy the key, it's not on the page. */
79 	if (sizeof(recno_t) > t->bt_rkey.size) {
80 		p = (void *)(t->bt_rkey.data == NULL ?
81 		    malloc(sizeof(recno_t)) :
82 		    realloc(t->bt_rkey.data, sizeof(recno_t)));
83 		if (p == NULL)
84 			return (RET_ERROR);
85 		t->bt_rkey.data = p;
86 		t->bt_rkey.size = sizeof(recno_t);
87 	}
88 	memmove(t->bt_rkey.data, &nrec, sizeof(recno_t));
89 	key->size = sizeof(recno_t);
90 	key->data = t->bt_rkey.data;
91 
92 dataonly:
93 	if (data == NULL)
94 		return (RET_SUCCESS);
95 
96 	/*
97 	 * We must copy big keys/data to make them contigous.  Otherwise,
98 	 * leave the page pinned and don't copy unless the user specified
99 	 * concurrent access.
100 	 */
101 	rl = GETRLEAF(e->page, e->index);
102 	if (rl->flags & P_BIGDATA) {
103 		if (__ovfl_get(t, rl->bytes,
104 		    &data->size, &t->bt_rdata.data, &t->bt_rdata.size))
105 			return (RET_ERROR);
106 		data->data = t->bt_rdata.data;
107 	} else if (F_ISSET(t, B_DB_LOCK)) {
108 		/* Use +1 in case the first record retrieved is 0 length. */
109 		if (rl->dsize + 1 > t->bt_rdata.size) {
110 			p = (void *)(t->bt_rdata.data == NULL ?
111 			    malloc(rl->dsize + 1) :
112 			    realloc(t->bt_rdata.data, rl->dsize + 1));
113 			if (p == NULL)
114 				return (RET_ERROR);
115 			t->bt_rdata.data = p;
116 			t->bt_rdata.size = rl->dsize + 1;
117 		}
118 		memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
119 		data->size = rl->dsize;
120 		data->data = t->bt_rdata.data;
121 	} else {
122 		data->size = rl->dsize;
123 		data->data = rl->bytes;
124 	}
125 	return (RET_SUCCESS);
126 }
127