xref: /openbsd-src/lib/libc/db/recno/rec_utils.c (revision bec2d00aee11811f26f3f148c6197e34c35176ed)
1 /*	$NetBSD: rec_utils.c,v 1.7 1996/05/03 21:38:54 cgd 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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #if 0
38 static char sccsid[] = "@(#)rec_utils.c	8.6 (Berkeley) 7/16/94";
39 #else
40 static char rcsid[] = "$NetBSD: rec_utils.c,v 1.7 1996/05/03 21:38:54 cgd Exp $";
41 #endif
42 #endif /* LIBC_SCCS and not lint */
43 
44 #include <sys/param.h>
45 
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 
50 #include <db.h>
51 #include "recno.h"
52 
53 /*
54  * __rec_ret --
55  *	Build return data.
56  *
57  * Parameters:
58  *	t:	tree
59  *	e:	key/data pair to be returned
60  *   nrec:	record number
61  *    key:	user's key structure
62  *	data:	user's data structure
63  *
64  * Returns:
65  *	RET_SUCCESS, RET_ERROR.
66  */
67 int
68 __rec_ret(t, e, nrec, key, data)
69 	BTREE *t;
70 	EPG *e;
71 	recno_t nrec;
72 	DBT *key, *data;
73 {
74 	RLEAF *rl;
75 	void *p;
76 
77 	if (key == NULL)
78 		goto dataonly;
79 
80 	/* We have to copy the key, it's not on the page. */
81 	if (sizeof(recno_t) > t->bt_rkey.size) {
82 		p = (void *)(t->bt_rkey.data == NULL ?
83 		    malloc(sizeof(recno_t)) :
84 		    realloc(t->bt_rkey.data, sizeof(recno_t)));
85 		if (p == NULL)
86 			return (RET_ERROR);
87 		t->bt_rkey.data = p;
88 		t->bt_rkey.size = sizeof(recno_t);
89 	}
90 	memmove(t->bt_rkey.data, &nrec, sizeof(recno_t));
91 	key->size = sizeof(recno_t);
92 	key->data = t->bt_rkey.data;
93 
94 dataonly:
95 	if (data == NULL)
96 		return (RET_SUCCESS);
97 
98 	/*
99 	 * We must copy big keys/data to make them contigous.  Otherwise,
100 	 * leave the page pinned and don't copy unless the user specified
101 	 * concurrent access.
102 	 */
103 	rl = GETRLEAF(e->page, e->index);
104 	if (rl->flags & P_BIGDATA) {
105 		if (__ovfl_get(t, rl->bytes,
106 		    &data->size, &t->bt_rdata.data, &t->bt_rdata.size))
107 			return (RET_ERROR);
108 		data->data = t->bt_rdata.data;
109 	} else if (F_ISSET(t, B_DB_LOCK)) {
110 		/* Use +1 in case the first record retrieved is 0 length. */
111 		if (rl->dsize + 1 > t->bt_rdata.size) {
112 			p = (void *)(t->bt_rdata.data == NULL ?
113 			    malloc(rl->dsize + 1) :
114 			    realloc(t->bt_rdata.data, rl->dsize + 1));
115 			if (p == NULL)
116 				return (RET_ERROR);
117 			t->bt_rdata.data = p;
118 			t->bt_rdata.size = rl->dsize + 1;
119 		}
120 		memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
121 		data->size = rl->dsize;
122 		data->data = t->bt_rdata.data;
123 	} else {
124 		data->size = rl->dsize;
125 		data->data = rl->bytes;
126 	}
127 	return (RET_SUCCESS);
128 }
129