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. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)bt_conv.c 8.5 (Berkeley) 8/17/94 37 */ 38 39 #include <sys/param.h> 40 41 #include <stdio.h> 42 43 #include <db.h> 44 #include "btree.h" 45 46 static void mswap __P((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 */ 58 void 59 __bt_pgin(t, pg, pp) 60 void *t; 61 pgno_t pg; 62 void *pp; 63 { 64 PAGE *h; 65 indx_t i, top; 66 u_char flags; 67 char *p; 68 69 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) 70 return; 71 if (pg == P_META) { 72 mswap(pp); 73 return; 74 } 75 76 h = pp; 77 M_32_SWAP(h->pgno); 78 M_32_SWAP(h->prevpg); 79 M_32_SWAP(h->nextpg); 80 M_32_SWAP(h->flags); 81 M_16_SWAP(h->lower); 82 M_16_SWAP(h->upper); 83 84 top = NEXTINDEX(h); 85 if ((h->flags & P_TYPE) == P_BINTERNAL) 86 for (i = 0; i < top; i++) { 87 M_16_SWAP(h->linp[i]); 88 p = (char *)GETBINTERNAL(h, i); 89 P_32_SWAP(p); 90 p += sizeof(u_int32_t); 91 P_32_SWAP(p); 92 p += sizeof(pgno_t); 93 if (*(u_char *)p & P_BIGKEY) { 94 p += sizeof(u_char); 95 P_32_SWAP(p); 96 p += sizeof(pgno_t); 97 P_32_SWAP(p); 98 } 99 } 100 else if ((h->flags & P_TYPE) == P_BLEAF) 101 for (i = 0; i < top; i++) { 102 M_16_SWAP(h->linp[i]); 103 p = (char *)GETBLEAF(h, i); 104 P_32_SWAP(p); 105 p += sizeof(u_int32_t); 106 P_32_SWAP(p); 107 p += sizeof(u_int32_t); 108 flags = *(u_char *)p; 109 if (flags & (P_BIGKEY | P_BIGDATA)) { 110 p += sizeof(u_char); 111 if (flags & P_BIGKEY) { 112 P_32_SWAP(p); 113 p += sizeof(pgno_t); 114 P_32_SWAP(p); 115 } 116 if (flags & P_BIGDATA) { 117 p += sizeof(u_int32_t); 118 P_32_SWAP(p); 119 p += sizeof(pgno_t); 120 P_32_SWAP(p); 121 } 122 } 123 } 124 } 125 126 void 127 __bt_pgout(t, pg, pp) 128 void *t; 129 pgno_t pg; 130 void *pp; 131 { 132 PAGE *h; 133 indx_t i, top; 134 u_char flags; 135 char *p; 136 137 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) 138 return; 139 if (pg == P_META) { 140 mswap(pp); 141 return; 142 } 143 144 h = pp; 145 top = NEXTINDEX(h); 146 if ((h->flags & P_TYPE) == P_BINTERNAL) 147 for (i = 0; i < top; i++) { 148 p = (char *)GETBINTERNAL(h, i); 149 P_32_SWAP(p); 150 p += sizeof(u_int32_t); 151 P_32_SWAP(p); 152 p += sizeof(pgno_t); 153 if (*(u_char *)p & P_BIGKEY) { 154 p += sizeof(u_char); 155 P_32_SWAP(p); 156 p += sizeof(pgno_t); 157 P_32_SWAP(p); 158 } 159 M_16_SWAP(h->linp[i]); 160 } 161 else if ((h->flags & P_TYPE) == P_BLEAF) 162 for (i = 0; i < top; i++) { 163 p = (char *)GETBLEAF(h, i); 164 P_32_SWAP(p); 165 p += sizeof(u_int32_t); 166 P_32_SWAP(p); 167 p += sizeof(u_int32_t); 168 flags = *(u_char *)p; 169 if (flags & (P_BIGKEY | P_BIGDATA)) { 170 p += sizeof(u_char); 171 if (flags & P_BIGKEY) { 172 P_32_SWAP(p); 173 p += sizeof(pgno_t); 174 P_32_SWAP(p); 175 } 176 if (flags & P_BIGDATA) { 177 p += sizeof(u_int32_t); 178 P_32_SWAP(p); 179 p += sizeof(pgno_t); 180 P_32_SWAP(p); 181 } 182 } 183 M_16_SWAP(h->linp[i]); 184 } 185 186 M_32_SWAP(h->pgno); 187 M_32_SWAP(h->prevpg); 188 M_32_SWAP(h->nextpg); 189 M_32_SWAP(h->flags); 190 M_16_SWAP(h->lower); 191 M_16_SWAP(h->upper); 192 } 193 194 /* 195 * MSWAP -- Actually swap the bytes on the meta page. 196 * 197 * Parameters: 198 * p: page to convert 199 */ 200 static void 201 mswap(pg) 202 PAGE *pg; 203 { 204 char *p; 205 206 p = (char *)pg; 207 P_32_SWAP(p); /* magic */ 208 p += sizeof(u_int32_t); 209 P_32_SWAP(p); /* version */ 210 p += sizeof(u_int32_t); 211 P_32_SWAP(p); /* psize */ 212 p += sizeof(u_int32_t); 213 P_32_SWAP(p); /* free */ 214 p += sizeof(u_int32_t); 215 P_32_SWAP(p); /* nrecs */ 216 p += sizeof(u_int32_t); 217 P_32_SWAP(p); /* flags */ 218 p += sizeof(u_int32_t); 219 } 220