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)
36 static char sccsid[] = "@(#)bt_conv.c 8.5 (Berkeley) 8/17/94";
37 #endif /* LIBC_SCCS and not lint */
38 #include <sys/param.h>
39
40 #include <stdio.h>
41
42 #include <db.h>
43 #include "btree.h"
44
45 static void mswap(PAGE *);
46
47 /*
48 * __BT_BPGIN, __BT_BPGOUT --
49 * Convert host-specific number layout to/from the host-independent
50 * format stored on disk.
51 *
52 * Parameters:
53 * t: tree
54 * pg: page number
55 * h: page to convert
56 */
57 void
__bt_pgin(void * t,pgno_t pg,void * pp)58 __bt_pgin(void *t, pgno_t pg, void *pp)
59 {
60 PAGE *h;
61 indx_t i, top;
62 u_char flags;
63 char *p;
64
65 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
66 return;
67 if (pg == P_META) {
68 mswap(pp);
69 return;
70 }
71
72 h = pp;
73 M_32_SWAP(h->pgno);
74 M_32_SWAP(h->prevpg);
75 M_32_SWAP(h->nextpg);
76 M_32_SWAP(h->flags);
77 M_16_SWAP(h->lower);
78 M_16_SWAP(h->upper);
79
80 top = NEXTINDEX(h);
81 if ((h->flags & P_TYPE) == P_BINTERNAL)
82 for (i = 0; i < top; i++) {
83 M_16_SWAP(h->linp[i]);
84 p = (char *)GETBINTERNAL(h, i);
85 P_32_SWAP(p);
86 p += sizeof(u_int32_t);
87 P_32_SWAP(p);
88 p += sizeof(pgno_t);
89 if (*(u_char *)p & P_BIGKEY) {
90 p += sizeof(u_char);
91 P_32_SWAP(p);
92 p += sizeof(pgno_t);
93 P_32_SWAP(p);
94 }
95 }
96 else if ((h->flags & P_TYPE) == P_BLEAF)
97 for (i = 0; i < top; i++) {
98 M_16_SWAP(h->linp[i]);
99 p = (char *)GETBLEAF(h, i);
100 P_32_SWAP(p);
101 p += sizeof(u_int32_t);
102 P_32_SWAP(p);
103 p += sizeof(u_int32_t);
104 flags = *(u_char *)p;
105 if (flags & (P_BIGKEY | P_BIGDATA)) {
106 p += sizeof(u_char);
107 if (flags & P_BIGKEY) {
108 P_32_SWAP(p);
109 p += sizeof(pgno_t);
110 P_32_SWAP(p);
111 }
112 if (flags & P_BIGDATA) {
113 p += sizeof(u_int32_t);
114 P_32_SWAP(p);
115 p += sizeof(pgno_t);
116 P_32_SWAP(p);
117 }
118 }
119 }
120 }
121
122 void
__bt_pgout(void * t,pgno_t pg,void * pp)123 __bt_pgout(void *t, pgno_t pg, void *pp)
124 {
125 PAGE *h;
126 indx_t i, top;
127 u_char flags;
128 char *p;
129
130 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
131 return;
132 if (pg == P_META) {
133 mswap(pp);
134 return;
135 }
136
137 h = pp;
138 top = NEXTINDEX(h);
139 if ((h->flags & P_TYPE) == P_BINTERNAL)
140 for (i = 0; i < top; i++) {
141 p = (char *)GETBINTERNAL(h, i);
142 P_32_SWAP(p);
143 p += sizeof(u_int32_t);
144 P_32_SWAP(p);
145 p += sizeof(pgno_t);
146 if (*(u_char *)p & P_BIGKEY) {
147 p += sizeof(u_char);
148 P_32_SWAP(p);
149 p += sizeof(pgno_t);
150 P_32_SWAP(p);
151 }
152 M_16_SWAP(h->linp[i]);
153 }
154 else if ((h->flags & P_TYPE) == P_BLEAF)
155 for (i = 0; i < top; i++) {
156 p = (char *)GETBLEAF(h, i);
157 P_32_SWAP(p);
158 p += sizeof(u_int32_t);
159 P_32_SWAP(p);
160 p += sizeof(u_int32_t);
161 flags = *(u_char *)p;
162 if (flags & (P_BIGKEY | P_BIGDATA)) {
163 p += sizeof(u_char);
164 if (flags & P_BIGKEY) {
165 P_32_SWAP(p);
166 p += sizeof(pgno_t);
167 P_32_SWAP(p);
168 }
169 if (flags & P_BIGDATA) {
170 p += sizeof(u_int32_t);
171 P_32_SWAP(p);
172 p += sizeof(pgno_t);
173 P_32_SWAP(p);
174 }
175 }
176 M_16_SWAP(h->linp[i]);
177 }
178
179 M_32_SWAP(h->pgno);
180 M_32_SWAP(h->prevpg);
181 M_32_SWAP(h->nextpg);
182 M_32_SWAP(h->flags);
183 M_16_SWAP(h->lower);
184 M_16_SWAP(h->upper);
185 }
186
187 /*
188 * MSWAP -- Actually swap the bytes on the meta page.
189 *
190 * Parameters:
191 * p: page to convert
192 */
193 static void
mswap(PAGE * pg)194 mswap(PAGE *pg)
195 {
196 char *p;
197
198 p = (char *)pg;
199 P_32_SWAP(p); /* magic */
200 p += sizeof(u_int32_t);
201 P_32_SWAP(p); /* version */
202 p += sizeof(u_int32_t);
203 P_32_SWAP(p); /* psize */
204 p += sizeof(u_int32_t);
205 P_32_SWAP(p); /* free */
206 p += sizeof(u_int32_t);
207 P_32_SWAP(p); /* nrecs */
208 p += sizeof(u_int32_t);
209 P_32_SWAP(p); /* flags */
210 p += sizeof(u_int32_t);
211 }
212