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This source file includes following definitions.
- __bt_pgin
- __bt_pgout
- mswap
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 * 3. 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)
34 static char sccsid[] = "@(#)bt_conv.c 8.5 (Berkeley) 8/17/94";
35 #endif /* LIBC_SCCS and not lint */
36
37 #ifdef HAVE_CONFIG_H
38 #include <config.h>
39 #endif
40 #include <stdio.h>
41
42 #include "db.h"
43 #include "btree.h"
44
45 static void mswap(PAGE *);
46
47 /**
48 * __BT_BPGIN --
49 * Convert host-specific number layout to/from the host-independent
50 * format stored on disk.
51 *
52 * @param t tree
53 * @param pg page number
54 * @param pp page to convert
55 */
56 void
57 __bt_pgin(t, pg, pp)
58 void *t;
59 pgno_t pg;
60 void *pp;
61 {
62 PAGE *h;
63 indx_t i, top;
64 u_char flags;
65 char *p;
66
67 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
68 return;
69 if (pg == P_META) {
70 mswap(pp);
71 return;
72 }
73
74 h = pp;
75 M_32_SWAP(h->pgno);
76 M_32_SWAP(h->prevpg);
77 M_32_SWAP(h->nextpg);
78 M_32_SWAP(h->flags);
79 M_16_SWAP(h->lower);
80 M_16_SWAP(h->upper);
81
82 top = NEXTINDEX(h);
83 if ((h->flags & P_TYPE) == P_BINTERNAL)
84 for (i = 0; i < top; i++) {
85 M_16_SWAP(h->linp[i]);
86 p = (char *)GETBINTERNAL(h, i);
87 P_32_SWAP(p);
88 p += sizeof(u_int32_t);
89 P_32_SWAP(p);
90 p += sizeof(pgno_t);
91 if (*(u_char *)p & P_BIGKEY) {
92 p += sizeof(u_char);
93 P_32_SWAP(p);
94 p += sizeof(pgno_t);
95 P_32_SWAP(p);
96 }
97 }
98 else if ((h->flags & P_TYPE) == P_BLEAF)
99 for (i = 0; i < top; i++) {
100 M_16_SWAP(h->linp[i]);
101 p = (char *)GETBLEAF(h, i);
102 P_32_SWAP(p);
103 p += sizeof(u_int32_t);
104 P_32_SWAP(p);
105 p += sizeof(u_int32_t);
106 flags = *(u_char *)p;
107 if (flags & (P_BIGKEY | P_BIGDATA)) {
108 p += sizeof(u_char);
109 if (flags & P_BIGKEY) {
110 P_32_SWAP(p);
111 p += sizeof(pgno_t);
112 P_32_SWAP(p);
113 }
114 if (flags & P_BIGDATA) {
115 p += sizeof(u_int32_t);
116 P_32_SWAP(p);
117 p += sizeof(pgno_t);
118 P_32_SWAP(p);
119 }
120 }
121 }
122 }
123
124 /**
125 * __BT_BPGOUT --
126 * Convert host-specific number layout to/from the host-independent
127 * format stored on disk.
128 *
129 * @param t tree
130 * @param pg page number
131 * @param pp page to convert
132 */
133 void
134 __bt_pgout(t, pg, pp)
135 void *t;
136 pgno_t pg;
137 void *pp;
138 {
139 PAGE *h;
140 indx_t i, top;
141 u_char flags;
142 char *p;
143
144 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP))
145 return;
146 if (pg == P_META) {
147 mswap(pp);
148 return;
149 }
150
151 h = pp;
152 top = NEXTINDEX(h);
153 if ((h->flags & P_TYPE) == P_BINTERNAL)
154 for (i = 0; i < top; i++) {
155 p = (char *)GETBINTERNAL(h, i);
156 P_32_SWAP(p);
157 p += sizeof(u_int32_t);
158 P_32_SWAP(p);
159 p += sizeof(pgno_t);
160 if (*(u_char *)p & P_BIGKEY) {
161 p += sizeof(u_char);
162 P_32_SWAP(p);
163 p += sizeof(pgno_t);
164 P_32_SWAP(p);
165 }
166 M_16_SWAP(h->linp[i]);
167 }
168 else if ((h->flags & P_TYPE) == P_BLEAF)
169 for (i = 0; i < top; i++) {
170 p = (char *)GETBLEAF(h, i);
171 P_32_SWAP(p);
172 p += sizeof(u_int32_t);
173 P_32_SWAP(p);
174 p += sizeof(u_int32_t);
175 flags = *(u_char *)p;
176 if (flags & (P_BIGKEY | P_BIGDATA)) {
177 p += sizeof(u_char);
178 if (flags & P_BIGKEY) {
179 P_32_SWAP(p);
180 p += sizeof(pgno_t);
181 P_32_SWAP(p);
182 }
183 if (flags & P_BIGDATA) {
184 p += sizeof(u_int32_t);
185 P_32_SWAP(p);
186 p += sizeof(pgno_t);
187 P_32_SWAP(p);
188 }
189 }
190 M_16_SWAP(h->linp[i]);
191 }
192
193 M_32_SWAP(h->pgno);
194 M_32_SWAP(h->prevpg);
195 M_32_SWAP(h->nextpg);
196 M_32_SWAP(h->flags);
197 M_16_SWAP(h->lower);
198 M_16_SWAP(h->upper);
199 }
200
201 /**
202 * MSWAP -- Actually swap the bytes on the meta page.
203 *
204 * @param pg page to convert
205 */
206 static void
207 mswap(pg)
208 PAGE *pg;
209 {
210 char *p;
211
212 p = (char *)pg;
213 P_32_SWAP(p); /* magic */
214 p += sizeof(u_int32_t);
215 P_32_SWAP(p); /* version */
216 p += sizeof(u_int32_t);
217 P_32_SWAP(p); /* psize */
218 p += sizeof(u_int32_t);
219 P_32_SWAP(p); /* free */
220 p += sizeof(u_int32_t);
221 P_32_SWAP(p); /* nrecs */
222 p += sizeof(u_int32_t);
223 P_32_SWAP(p); /* flags */
224 #if 0 /* To satisfy compiler */
225 p += sizeof(u_int32_t);
226 #endif
227 }
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