1 /* $OpenBSD: bt_conv.c,v 1.10 2015/01/16 16:48:51 deraadt Exp $ */
2
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 #include <stdio.h>
36
37 #include <db.h>
38 #include "btree.h"
39
40 static void mswap(PAGE *);
41
42 /*
43 * __BT_BPGIN, __BT_BPGOUT --
44 * Convert host-specific number layout to/from the host-independent
45 * format stored on disk.
46 *
47 * Parameters:
48 * t: tree
49 * pg: page number
50 * h: page to convert
51 */
52 void
__bt_pgin(void * t,pgno_t pg,void * pp)53 __bt_pgin(void *t, pgno_t pg, void *pp)
54 {
55 PAGE *h;
56 indx_t i, top;
57 u_char flags;
58 char *p;
59
60 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
61 return;
62 if (pg == P_META) {
63 mswap(pp);
64 return;
65 }
66
67 h = pp;
68 M_32_SWAP(h->pgno);
69 M_32_SWAP(h->prevpg);
70 M_32_SWAP(h->nextpg);
71 M_32_SWAP(h->flags);
72 M_16_SWAP(h->lower);
73 M_16_SWAP(h->upper);
74
75 top = NEXTINDEX(h);
76 if ((h->flags & P_TYPE) == P_BINTERNAL)
77 for (i = 0; i < top; i++) {
78 M_16_SWAP(h->linp[i]);
79 p = (char *)GETBINTERNAL(h, i);
80 P_32_SWAP(p);
81 p += sizeof(u_int32_t);
82 P_32_SWAP(p);
83 p += sizeof(pgno_t);
84 if (*(u_char *)p & P_BIGKEY) {
85 p += sizeof(u_char);
86 P_32_SWAP(p);
87 p += sizeof(pgno_t);
88 P_32_SWAP(p);
89 }
90 }
91 else if ((h->flags & P_TYPE) == P_BLEAF)
92 for (i = 0; i < top; i++) {
93 M_16_SWAP(h->linp[i]);
94 p = (char *)GETBLEAF(h, i);
95 P_32_SWAP(p);
96 p += sizeof(u_int32_t);
97 P_32_SWAP(p);
98 p += sizeof(u_int32_t);
99 flags = *(u_char *)p;
100 if (flags & (P_BIGKEY | P_BIGDATA)) {
101 p += sizeof(u_char);
102 if (flags & P_BIGKEY) {
103 P_32_SWAP(p);
104 p += sizeof(pgno_t);
105 P_32_SWAP(p);
106 }
107 if (flags & P_BIGDATA) {
108 p += sizeof(u_int32_t);
109 P_32_SWAP(p);
110 p += sizeof(pgno_t);
111 P_32_SWAP(p);
112 }
113 }
114 }
115 }
116
117 void
__bt_pgout(void * t,pgno_t pg,void * pp)118 __bt_pgout(void *t, pgno_t pg, void *pp)
119 {
120 PAGE *h;
121 indx_t i, top;
122 u_char flags;
123 char *p;
124
125 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
126 return;
127 if (pg == P_META) {
128 mswap(pp);
129 return;
130 }
131
132 h = pp;
133 top = NEXTINDEX(h);
134 if ((h->flags & P_TYPE) == P_BINTERNAL)
135 for (i = 0; i < top; i++) {
136 p = (char *)GETBINTERNAL(h, i);
137 P_32_SWAP(p);
138 p += sizeof(u_int32_t);
139 P_32_SWAP(p);
140 p += sizeof(pgno_t);
141 if (*(u_char *)p & P_BIGKEY) {
142 p += sizeof(u_char);
143 P_32_SWAP(p);
144 p += sizeof(pgno_t);
145 P_32_SWAP(p);
146 }
147 M_16_SWAP(h->linp[i]);
148 }
149 else if ((h->flags & P_TYPE) == P_BLEAF)
150 for (i = 0; i < top; i++) {
151 p = (char *)GETBLEAF(h, i);
152 P_32_SWAP(p);
153 p += sizeof(u_int32_t);
154 P_32_SWAP(p);
155 p += sizeof(u_int32_t);
156 flags = *(u_char *)p;
157 if (flags & (P_BIGKEY | P_BIGDATA)) {
158 p += sizeof(u_char);
159 if (flags & P_BIGKEY) {
160 P_32_SWAP(p);
161 p += sizeof(pgno_t);
162 P_32_SWAP(p);
163 }
164 if (flags & P_BIGDATA) {
165 p += sizeof(u_int32_t);
166 P_32_SWAP(p);
167 p += sizeof(pgno_t);
168 P_32_SWAP(p);
169 }
170 }
171 M_16_SWAP(h->linp[i]);
172 }
173
174 M_32_SWAP(h->pgno);
175 M_32_SWAP(h->prevpg);
176 M_32_SWAP(h->nextpg);
177 M_32_SWAP(h->flags);
178 M_16_SWAP(h->lower);
179 M_16_SWAP(h->upper);
180 }
181
182 /*
183 * MSWAP -- Actually swap the bytes on the meta page.
184 *
185 * Parameters:
186 * p: page to convert
187 */
188 static void
mswap(PAGE * pg)189 mswap(PAGE *pg)
190 {
191 char *p;
192
193 p = (char *)pg;
194 P_32_SWAP(p); /* magic */
195 p += sizeof(u_int32_t);
196 P_32_SWAP(p); /* version */
197 p += sizeof(u_int32_t);
198 P_32_SWAP(p); /* psize */
199 p += sizeof(u_int32_t);
200 P_32_SWAP(p); /* free */
201 p += sizeof(u_int32_t);
202 P_32_SWAP(p); /* nrecs */
203 p += sizeof(u_int32_t);
204 P_32_SWAP(p); /* flags */
205 p += sizeof(u_int32_t);
206 }
207