1/*-
2 * Copyright (c) 1990, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Mike Olson.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#if defined(LIBC_SCCS) && !defined(lint)
34static char sccsid[] = "@(#)bt_conv.c	8.5 (Berkeley) 8/17/94";
35#endif /* LIBC_SCCS and not lint */
36#include <sys/cdefs.h>
37__FBSDID("$FreeBSD: releng/10.3/lib/libc/db/btree/bt_conv.c 189291 2009-03-02 23:47:18Z delphij $");
38
39#include <sys/param.h>
40
41#include <stdio.h>
42
43#include <db.h>
44#include "btree.h"
45
46static void mswap(PAGE *);
47
48/*
49 * __BT_BPGIN, __BT_BPGOUT --
50 *	Convert host-specific number layout to/from the host-independent
51 *	format stored on disk.
52 *
53 * Parameters:
54 *	t:	tree
55 *	pg:	page number
56 *	h:	page to convert
57 */
58void
59__bt_pgin(void *t, pgno_t pg, void *pp)
60{
61	PAGE *h;
62	indx_t i, top;
63	u_char flags;
64	char *p;
65
66	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
67		return;
68	if (pg == P_META) {
69		mswap(pp);
70		return;
71	}
72
73	h = pp;
74	M_32_SWAP(h->pgno);
75	M_32_SWAP(h->prevpg);
76	M_32_SWAP(h->nextpg);
77	M_32_SWAP(h->flags);
78	M_16_SWAP(h->lower);
79	M_16_SWAP(h->upper);
80
81	top = NEXTINDEX(h);
82	if ((h->flags & P_TYPE) == P_BINTERNAL)
83		for (i = 0; i < top; i++) {
84			M_16_SWAP(h->linp[i]);
85			p = (char *)GETBINTERNAL(h, i);
86			P_32_SWAP(p);
87			p += sizeof(u_int32_t);
88			P_32_SWAP(p);
89			p += sizeof(pgno_t);
90			if (*(u_char *)p & P_BIGKEY) {
91				p += sizeof(u_char);
92				P_32_SWAP(p);
93				p += sizeof(pgno_t);
94				P_32_SWAP(p);
95			}
96		}
97	else if ((h->flags & P_TYPE) == P_BLEAF)
98		for (i = 0; i < top; i++) {
99			M_16_SWAP(h->linp[i]);
100			p = (char *)GETBLEAF(h, i);
101			P_32_SWAP(p);
102			p += sizeof(u_int32_t);
103			P_32_SWAP(p);
104			p += sizeof(u_int32_t);
105			flags = *(u_char *)p;
106			if (flags & (P_BIGKEY | P_BIGDATA)) {
107				p += sizeof(u_char);
108				if (flags & P_BIGKEY) {
109					P_32_SWAP(p);
110					p += sizeof(pgno_t);
111					P_32_SWAP(p);
112				}
113				if (flags & P_BIGDATA) {
114					p += sizeof(u_int32_t);
115					P_32_SWAP(p);
116					p += sizeof(pgno_t);
117					P_32_SWAP(p);
118				}
119			}
120		}
121}
122
123void
124__bt_pgout(void *t, pgno_t pg, void *pp)
125{
126	PAGE *h;
127	indx_t i, top;
128	u_char flags;
129	char *p;
130
131	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
132		return;
133	if (pg == P_META) {
134		mswap(pp);
135		return;
136	}
137
138	h = pp;
139	top = NEXTINDEX(h);
140	if ((h->flags & P_TYPE) == P_BINTERNAL)
141		for (i = 0; i < top; i++) {
142			p = (char *)GETBINTERNAL(h, i);
143			P_32_SWAP(p);
144			p += sizeof(u_int32_t);
145			P_32_SWAP(p);
146			p += sizeof(pgno_t);
147			if (*(u_char *)p & P_BIGKEY) {
148				p += sizeof(u_char);
149				P_32_SWAP(p);
150				p += sizeof(pgno_t);
151				P_32_SWAP(p);
152			}
153			M_16_SWAP(h->linp[i]);
154		}
155	else if ((h->flags & P_TYPE) == P_BLEAF)
156		for (i = 0; i < top; i++) {
157			p = (char *)GETBLEAF(h, i);
158			P_32_SWAP(p);
159			p += sizeof(u_int32_t);
160			P_32_SWAP(p);
161			p += sizeof(u_int32_t);
162			flags = *(u_char *)p;
163			if (flags & (P_BIGKEY | P_BIGDATA)) {
164				p += sizeof(u_char);
165				if (flags & P_BIGKEY) {
166					P_32_SWAP(p);
167					p += sizeof(pgno_t);
168					P_32_SWAP(p);
169				}
170				if (flags & P_BIGDATA) {
171					p += sizeof(u_int32_t);
172					P_32_SWAP(p);
173					p += sizeof(pgno_t);
174					P_32_SWAP(p);
175				}
176			}
177			M_16_SWAP(h->linp[i]);
178		}
179
180	M_32_SWAP(h->pgno);
181	M_32_SWAP(h->prevpg);
182	M_32_SWAP(h->nextpg);
183	M_32_SWAP(h->flags);
184	M_16_SWAP(h->lower);
185	M_16_SWAP(h->upper);
186}
187
188/*
189 * MSWAP -- Actually swap the bytes on the meta page.
190 *
191 * Parameters:
192 *	p:	page to convert
193 */
194static void
195mswap(PAGE *pg)
196{
197	char *p;
198
199	p = (char *)pg;
200	P_32_SWAP(p);		/* magic */
201	p += sizeof(u_int32_t);
202	P_32_SWAP(p);		/* version */
203	p += sizeof(u_int32_t);
204	P_32_SWAP(p);		/* psize */
205	p += sizeof(u_int32_t);
206	P_32_SWAP(p);		/* free */
207	p += sizeof(u_int32_t);
208	P_32_SWAP(p);		/* nrecs */
209	p += sizeof(u_int32_t);
210	P_32_SWAP(p);		/* flags */
211	p += sizeof(u_int32_t);
212}
213