1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1990, 1993, 1994
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Mike Olson.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#if defined(LIBC_SCCS) && !defined(lint)
36static char sccsid[] = "@(#)bt_conv.c	8.5 (Berkeley) 8/17/94";
37#endif /* LIBC_SCCS and not lint */
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD$");
40
41#include <sys/param.h>
42
43#include <stdio.h>
44
45#include <db.h>
46#include "btree.h"
47
48static void mswap(PAGE *);
49
50/*
51 * __BT_BPGIN, __BT_BPGOUT --
52 *	Convert host-specific number layout to/from the host-independent
53 *	format stored on disk.
54 *
55 * Parameters:
56 *	t:	tree
57 *	pg:	page number
58 *	h:	page to convert
59 */
60void
61__bt_pgin(void *t, pgno_t pg, void *pp)
62{
63	PAGE *h;
64	indx_t i, top;
65	u_char flags;
66	char *p;
67
68	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
69		return;
70	if (pg == P_META) {
71		mswap(pp);
72		return;
73	}
74
75	h = pp;
76	M_32_SWAP(h->pgno);
77	M_32_SWAP(h->prevpg);
78	M_32_SWAP(h->nextpg);
79	M_32_SWAP(h->flags);
80	M_16_SWAP(h->lower);
81	M_16_SWAP(h->upper);
82
83	top = NEXTINDEX(h);
84	if ((h->flags & P_TYPE) == P_BINTERNAL)
85		for (i = 0; i < top; i++) {
86			M_16_SWAP(h->linp[i]);
87			p = (char *)GETBINTERNAL(h, i);
88			P_32_SWAP(p);
89			p += sizeof(u_int32_t);
90			P_32_SWAP(p);
91			p += sizeof(pgno_t);
92			if (*(u_char *)p & P_BIGKEY) {
93				p += sizeof(u_char);
94				P_32_SWAP(p);
95				p += sizeof(pgno_t);
96				P_32_SWAP(p);
97			}
98		}
99	else if ((h->flags & P_TYPE) == P_BLEAF)
100		for (i = 0; i < top; i++) {
101			M_16_SWAP(h->linp[i]);
102			p = (char *)GETBLEAF(h, i);
103			P_32_SWAP(p);
104			p += sizeof(u_int32_t);
105			P_32_SWAP(p);
106			p += sizeof(u_int32_t);
107			flags = *(u_char *)p;
108			if (flags & (P_BIGKEY | P_BIGDATA)) {
109				p += sizeof(u_char);
110				if (flags & P_BIGKEY) {
111					P_32_SWAP(p);
112					p += sizeof(pgno_t);
113					P_32_SWAP(p);
114				}
115				if (flags & P_BIGDATA) {
116					p += sizeof(u_int32_t);
117					P_32_SWAP(p);
118					p += sizeof(pgno_t);
119					P_32_SWAP(p);
120				}
121			}
122		}
123}
124
125void
126__bt_pgout(void *t, pgno_t pg, void *pp)
127{
128	PAGE *h;
129	indx_t i, top;
130	u_char flags;
131	char *p;
132
133	if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
134		return;
135	if (pg == P_META) {
136		mswap(pp);
137		return;
138	}
139
140	h = pp;
141	top = NEXTINDEX(h);
142	if ((h->flags & P_TYPE) == P_BINTERNAL)
143		for (i = 0; i < top; i++) {
144			p = (char *)GETBINTERNAL(h, i);
145			P_32_SWAP(p);
146			p += sizeof(u_int32_t);
147			P_32_SWAP(p);
148			p += sizeof(pgno_t);
149			if (*(u_char *)p & P_BIGKEY) {
150				p += sizeof(u_char);
151				P_32_SWAP(p);
152				p += sizeof(pgno_t);
153				P_32_SWAP(p);
154			}
155			M_16_SWAP(h->linp[i]);
156		}
157	else if ((h->flags & P_TYPE) == P_BLEAF)
158		for (i = 0; i < top; i++) {
159			p = (char *)GETBLEAF(h, i);
160			P_32_SWAP(p);
161			p += sizeof(u_int32_t);
162			P_32_SWAP(p);
163			p += sizeof(u_int32_t);
164			flags = *(u_char *)p;
165			if (flags & (P_BIGKEY | P_BIGDATA)) {
166				p += sizeof(u_char);
167				if (flags & P_BIGKEY) {
168					P_32_SWAP(p);
169					p += sizeof(pgno_t);
170					P_32_SWAP(p);
171				}
172				if (flags & P_BIGDATA) {
173					p += sizeof(u_int32_t);
174					P_32_SWAP(p);
175					p += sizeof(pgno_t);
176					P_32_SWAP(p);
177				}
178			}
179			M_16_SWAP(h->linp[i]);
180		}
181
182	M_32_SWAP(h->pgno);
183	M_32_SWAP(h->prevpg);
184	M_32_SWAP(h->nextpg);
185	M_32_SWAP(h->flags);
186	M_16_SWAP(h->lower);
187	M_16_SWAP(h->upper);
188}
189
190/*
191 * MSWAP -- Actually swap the bytes on the meta page.
192 *
193 * Parameters:
194 *	p:	page to convert
195 */
196static void
197mswap(PAGE *pg)
198{
199	char *p;
200
201	p = (char *)pg;
202	P_32_SWAP(p);		/* magic */
203	p += sizeof(u_int32_t);
204	P_32_SWAP(p);		/* version */
205	p += sizeof(u_int32_t);
206	P_32_SWAP(p);		/* psize */
207	p += sizeof(u_int32_t);
208	P_32_SWAP(p);		/* free */
209	p += sizeof(u_int32_t);
210	P_32_SWAP(p);		/* nrecs */
211	p += sizeof(u_int32_t);
212	P_32_SWAP(p);		/* flags */
213	p += sizeof(u_int32_t);
214}
215