1 /* $NetBSD: bt_conv.c,v 1.7 1997/07/13 18:51:49 christos 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. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 */ 38 39 #include <sys/cdefs.h> 40 #if defined(LIBC_SCCS) && !defined(lint) 41 #if 0 42 static char sccsid[] = "@(#)bt_conv.c 8.5 (Berkeley) 8/17/94"; 43 #else 44 __RCSID("$NetBSD: bt_conv.c,v 1.7 1997/07/13 18:51:49 christos Exp $"); 45 #endif 46 #endif /* LIBC_SCCS and not lint */ 47 48 #include <sys/param.h> 49 50 #include <stdio.h> 51 52 #include <db.h> 53 #include "btree.h" 54 55 static void mswap __P((PAGE *)); 56 57 /* 58 * __BT_BPGIN, __BT_BPGOUT -- 59 * Convert host-specific number layout to/from the host-independent 60 * format stored on disk. 61 * 62 * Parameters: 63 * t: tree 64 * pg: page number 65 * h: page to convert 66 */ 67 void 68 __bt_pgin(t, pg, pp) 69 void *t; 70 pgno_t pg; 71 void *pp; 72 { 73 PAGE *h; 74 indx_t i, top; 75 u_char flags; 76 char *p; 77 78 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) 79 return; 80 if (pg == P_META) { 81 mswap(pp); 82 return; 83 } 84 85 h = pp; 86 M_32_SWAP(h->pgno); 87 M_32_SWAP(h->prevpg); 88 M_32_SWAP(h->nextpg); 89 M_32_SWAP(h->flags); 90 M_16_SWAP(h->lower); 91 M_16_SWAP(h->upper); 92 93 top = NEXTINDEX(h); 94 if ((h->flags & P_TYPE) == P_BINTERNAL) 95 for (i = 0; i < top; i++) { 96 M_16_SWAP(h->linp[i]); 97 p = (char *)GETBINTERNAL(h, i); 98 P_32_SWAP(p); 99 p += sizeof(u_int32_t); 100 P_32_SWAP(p); 101 p += sizeof(pgno_t); 102 if (*(u_char *)p & P_BIGKEY) { 103 p += sizeof(u_char); 104 P_32_SWAP(p); 105 p += sizeof(pgno_t); 106 P_32_SWAP(p); 107 } 108 } 109 else if ((h->flags & P_TYPE) == P_BLEAF) 110 for (i = 0; i < top; i++) { 111 M_16_SWAP(h->linp[i]); 112 p = (char *)GETBLEAF(h, i); 113 P_32_SWAP(p); 114 p += sizeof(u_int32_t); 115 P_32_SWAP(p); 116 p += sizeof(u_int32_t); 117 flags = *(u_char *)p; 118 if (flags & (P_BIGKEY | P_BIGDATA)) { 119 p += sizeof(u_char); 120 if (flags & P_BIGKEY) { 121 P_32_SWAP(p); 122 p += sizeof(pgno_t); 123 P_32_SWAP(p); 124 } 125 if (flags & P_BIGDATA) { 126 p += sizeof(u_int32_t); 127 P_32_SWAP(p); 128 p += sizeof(pgno_t); 129 P_32_SWAP(p); 130 } 131 } 132 } 133 } 134 135 void 136 __bt_pgout(t, pg, pp) 137 void *t; 138 pgno_t pg; 139 void *pp; 140 { 141 PAGE *h; 142 indx_t i, top; 143 u_char flags; 144 char *p; 145 146 if (!F_ISSET(((BTREE *)t), B_NEEDSWAP)) 147 return; 148 if (pg == P_META) { 149 mswap(pp); 150 return; 151 } 152 153 h = pp; 154 top = NEXTINDEX(h); 155 if ((h->flags & P_TYPE) == P_BINTERNAL) 156 for (i = 0; i < top; i++) { 157 p = (char *)GETBINTERNAL(h, i); 158 P_32_SWAP(p); 159 p += sizeof(u_int32_t); 160 P_32_SWAP(p); 161 p += sizeof(pgno_t); 162 if (*(u_char *)p & P_BIGKEY) { 163 p += sizeof(u_char); 164 P_32_SWAP(p); 165 p += sizeof(pgno_t); 166 P_32_SWAP(p); 167 } 168 M_16_SWAP(h->linp[i]); 169 } 170 else if ((h->flags & P_TYPE) == P_BLEAF) 171 for (i = 0; i < top; i++) { 172 p = (char *)GETBLEAF(h, i); 173 P_32_SWAP(p); 174 p += sizeof(u_int32_t); 175 P_32_SWAP(p); 176 p += sizeof(u_int32_t); 177 flags = *(u_char *)p; 178 if (flags & (P_BIGKEY | P_BIGDATA)) { 179 p += sizeof(u_char); 180 if (flags & P_BIGKEY) { 181 P_32_SWAP(p); 182 p += sizeof(pgno_t); 183 P_32_SWAP(p); 184 } 185 if (flags & P_BIGDATA) { 186 p += sizeof(u_int32_t); 187 P_32_SWAP(p); 188 p += sizeof(pgno_t); 189 P_32_SWAP(p); 190 } 191 } 192 M_16_SWAP(h->linp[i]); 193 } 194 195 M_32_SWAP(h->pgno); 196 M_32_SWAP(h->prevpg); 197 M_32_SWAP(h->nextpg); 198 M_32_SWAP(h->flags); 199 M_16_SWAP(h->lower); 200 M_16_SWAP(h->upper); 201 } 202 203 /* 204 * MSWAP -- Actually swap the bytes on the meta page. 205 * 206 * Parameters: 207 * p: page to convert 208 */ 209 static void 210 mswap(pg) 211 PAGE *pg; 212 { 213 char *p; 214 215 p = (char *)pg; 216 P_32_SWAP(p); /* magic */ 217 p += sizeof(u_int32_t); 218 P_32_SWAP(p); /* version */ 219 p += sizeof(u_int32_t); 220 P_32_SWAP(p); /* psize */ 221 p += sizeof(u_int32_t); 222 P_32_SWAP(p); /* free */ 223 p += sizeof(u_int32_t); 224 P_32_SWAP(p); /* nrecs */ 225 p += sizeof(u_int32_t); 226 P_32_SWAP(p); /* flags */ 227 p += sizeof(u_int32_t); 228 } 229