xref: /netbsd-src/lib/libc/db/recno/rec_utils.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8)
1 /*	$NetBSD: rec_utils.c,v 1.9 2003/08/07 16:42:44 agc 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 #include <sys/cdefs.h>
33 #if defined(LIBC_SCCS) && !defined(lint)
34 #if 0
35 static char sccsid[] = "@(#)rec_utils.c	8.6 (Berkeley) 7/16/94";
36 #else
37 __RCSID("$NetBSD: rec_utils.c,v 1.9 2003/08/07 16:42:44 agc Exp $");
38 #endif
39 #endif /* LIBC_SCCS and not lint */
40 
41 #include <sys/param.h>
42 
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 
47 #include <db.h>
48 #include "recno.h"
49 
50 /*
51  * __rec_ret --
52  *	Build return data.
53  *
54  * Parameters:
55  *	t:	tree
56  *	e:	key/data pair to be returned
57  *   nrec:	record number
58  *    key:	user's key structure
59  *	data:	user's data structure
60  *
61  * Returns:
62  *	RET_SUCCESS, RET_ERROR.
63  */
64 int
65 __rec_ret(t, e, nrec, key, data)
66 	BTREE *t;
67 	EPG *e;
68 	recno_t nrec;
69 	DBT *key, *data;
70 {
71 	RLEAF *rl;
72 	void *p;
73 
74 	if (key == NULL)
75 		goto dataonly;
76 
77 	/* We have to copy the key, it's not on the page. */
78 	if (sizeof(recno_t) > t->bt_rkey.size) {
79 		p = (void *)(t->bt_rkey.data == NULL ?
80 		    malloc(sizeof(recno_t)) :
81 		    realloc(t->bt_rkey.data, sizeof(recno_t)));
82 		if (p == NULL)
83 			return (RET_ERROR);
84 		t->bt_rkey.data = p;
85 		t->bt_rkey.size = sizeof(recno_t);
86 	}
87 	memmove(t->bt_rkey.data, &nrec, sizeof(recno_t));
88 	key->size = sizeof(recno_t);
89 	key->data = t->bt_rkey.data;
90 
91 dataonly:
92 	if (data == NULL)
93 		return (RET_SUCCESS);
94 
95 	/*
96 	 * We must copy big keys/data to make them contigous.  Otherwise,
97 	 * leave the page pinned and don't copy unless the user specified
98 	 * concurrent access.
99 	 */
100 	rl = GETRLEAF(e->page, e->index);
101 	if (rl->flags & P_BIGDATA) {
102 		if (__ovfl_get(t, rl->bytes,
103 		    &data->size, &t->bt_rdata.data, &t->bt_rdata.size))
104 			return (RET_ERROR);
105 		data->data = t->bt_rdata.data;
106 	} else if (F_ISSET(t, B_DB_LOCK)) {
107 		/* Use +1 in case the first record retrieved is 0 length. */
108 		if (rl->dsize + 1 > t->bt_rdata.size) {
109 			p = (void *)(t->bt_rdata.data == NULL ?
110 			    malloc(rl->dsize + 1) :
111 			    realloc(t->bt_rdata.data, rl->dsize + 1));
112 			if (p == NULL)
113 				return (RET_ERROR);
114 			t->bt_rdata.data = p;
115 			t->bt_rdata.size = rl->dsize + 1;
116 		}
117 		memmove(t->bt_rdata.data, rl->bytes, rl->dsize);
118 		data->size = rl->dsize;
119 		data->data = t->bt_rdata.data;
120 	} else {
121 		data->size = rl->dsize;
122 		data->data = rl->bytes;
123 	}
124 	return (RET_SUCCESS);
125 }
126