1 /* $NetBSD: db.h,v 1.27 2016/09/24 20:11:43 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 1990, 1993, 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)db.h 8.7 (Berkeley) 6/16/94 32 */ 33 34 #ifndef _DB_H_ 35 #define _DB_H_ 36 37 #include <sys/types.h> 38 #include <sys/cdefs.h> 39 40 #include <limits.h> 41 42 #define RET_ERROR -1 /* Return values. */ 43 #define RET_SUCCESS 0 44 #define RET_SPECIAL 1 45 46 #define MAX_PAGE_NUMBER 0xffffffff /* >= # of pages in a file */ 47 typedef uint32_t pgno_t; 48 #define MAX_PAGE_OFFSET 65535 /* >= # of bytes in a page */ 49 typedef uint16_t indx_t; 50 #define MAX_REC_NUMBER 0xffffffff /* >= # of records in a tree */ 51 typedef uint32_t recno_t; 52 53 /* Key/data structure -- a Data-Base Thang. */ 54 typedef struct { 55 void *data; /* data */ 56 size_t size; /* data length */ 57 } DBT; 58 59 /* Routine flags. */ 60 #define R_CURSOR 1 /* del, put, seq */ 61 #define __R_UNUSED 2 /* UNUSED */ 62 #define R_FIRST 3 /* seq */ 63 #define R_IAFTER 4 /* put (RECNO) */ 64 #define R_IBEFORE 5 /* put (RECNO) */ 65 #define R_LAST 6 /* seq (BTREE, RECNO) */ 66 #define R_NEXT 7 /* seq */ 67 #define R_NOOVERWRITE 8 /* put */ 68 #define R_PREV 9 /* seq (BTREE, RECNO) */ 69 #define R_SETCURSOR 10 /* put (RECNO) */ 70 #define R_RECNOSYNC 11 /* sync (RECNO) */ 71 72 /* 73 * Recursive sequential scan. 74 * 75 * This avoids using sibling pointers, permitting (possibly partial) 76 * recovery from some kinds of btree corruption. Start a sequential 77 * scan as usual, but use R_RNEXT or R_RPREV to move forward or 78 * backward. 79 * 80 * This probably doesn't work with btrees that allow duplicate keys. 81 * Database modifications during the scan can also modify the parent 82 * page stack needed for correct functioning. Intermixing 83 * non-recursive traversal by using R_NEXT or R_PREV can also make the 84 * page stack inconsistent with the cursor and cause problems. 85 */ 86 #define R_RNEXT 128 /* seq (BTREE, RECNO) */ 87 #define R_RPREV 129 /* seq (BTREE, RECNO) */ 88 89 typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE; 90 91 /* 92 * !!! 93 * The following flags are included in the dbopen(3) call as part of the 94 * open(2) flags. In order to avoid conflicts with the open flags, start 95 * at the top of the 16 or 32-bit number space and work our way down. If 96 * the open flags were significantly expanded in the future, it could be 97 * a problem. Wish I'd left another flags word in the dbopen call. 98 * 99 * !!! 100 * None of this stuff is implemented yet. The only reason that it's here 101 * is so that the access methods can skip copying the key/data pair when 102 * the DB_LOCK flag isn't set. 103 */ 104 #if UINT_MAX > 65535 105 #define DB_LOCK 0x20000000 /* Do locking. */ 106 #define DB_SHMEM 0x40000000 /* Use shared memory. */ 107 #define DB_TXN 0x80000000 /* Do transactions. */ 108 #else 109 #define DB_LOCK 0x2000 /* Do locking. */ 110 #define DB_SHMEM 0x4000 /* Use shared memory. */ 111 #define DB_TXN 0x8000 /* Do transactions. */ 112 #endif 113 114 /* Access method description structure. */ 115 typedef struct __db { 116 DBTYPE type; /* Underlying db type. */ 117 int (*close) (struct __db *); 118 int (*del) (const struct __db *, const DBT *, unsigned int); 119 int (*get) (const struct __db *, const DBT *, DBT *, unsigned int); 120 int (*put) (const struct __db *, DBT *, const DBT *, unsigned int); 121 int (*seq) (const struct __db *, DBT *, DBT *, unsigned int); 122 int (*sync) (const struct __db *, unsigned int); 123 void *internal; /* Access method private. */ 124 int (*fd) (const struct __db *); 125 } DB; 126 127 #define BTREEMAGIC 0x053162 128 #define BTREEVERSION 3 129 130 /* Structure used to pass parameters to the btree routines. */ 131 typedef struct { 132 #define R_DUP 0x01 /* duplicate keys */ 133 unsigned long flags; 134 unsigned int cachesize; /* bytes to cache */ 135 int maxkeypage; /* maximum keys per page */ 136 int minkeypage; /* minimum keys per page */ 137 unsigned int psize; /* page size */ 138 int (*compare) /* comparison function */ 139 (const DBT *, const DBT *); 140 size_t (*prefix) /* prefix function */ 141 (const DBT *, const DBT *); 142 int lorder; /* byte order */ 143 } BTREEINFO; 144 145 #define HASHMAGIC 0x061561 146 #define HASHVERSION 2 147 148 /* Structure used to pass parameters to the hashing routines. */ 149 typedef struct { 150 unsigned int bsize; /* bucket size */ 151 unsigned int ffactor; /* fill factor */ 152 unsigned int nelem; /* number of elements */ 153 unsigned int cachesize; /* bytes to cache */ 154 uint32_t /* hash function */ 155 (*hash)(const void *, size_t); 156 int lorder; /* byte order */ 157 } HASHINFO; 158 159 /* Structure used to pass parameters to the record routines. */ 160 typedef struct { 161 #define R_FIXEDLEN 0x01 /* fixed-length records */ 162 #define R_NOKEY 0x02 /* key not required */ 163 #define R_SNAPSHOT 0x04 /* snapshot the input */ 164 unsigned long flags; 165 unsigned int cachesize; /* bytes to cache */ 166 unsigned int psize; /* page size */ 167 int lorder; /* byte order */ 168 size_t reclen; /* record length (fixed-length records) */ 169 uint8_t bval; /* delimiting byte (variable-length records */ 170 char *bfname; /* btree file name */ 171 } RECNOINFO; 172 173 #ifdef __DBINTERFACE_PRIVATE 174 /* 175 * Little endian <==> big endian 32-bit swap macros. 176 * M_32_SWAP swap a memory location 177 * P_32_SWAP swap a referenced memory location 178 * P_32_COPY swap from one location to another 179 */ 180 #define M_32_SWAP(a) { \ 181 uint32_t _tmp = a; \ 182 ((char *)(void *)&a)[0] = ((char *)(void *)&_tmp)[3]; \ 183 ((char *)(void *)&a)[1] = ((char *)(void *)&_tmp)[2]; \ 184 ((char *)(void *)&a)[2] = ((char *)(void *)&_tmp)[1]; \ 185 ((char *)(void *)&a)[3] = ((char *)(void *)&_tmp)[0]; \ 186 } 187 #define P_32_SWAP(a) { \ 188 char _tmp[4]; \ 189 _tmp[0] = ((char *)(void *)a)[0]; \ 190 _tmp[1] = ((char *)(void *)a)[1]; \ 191 _tmp[2] = ((char *)(void *)a)[2]; \ 192 _tmp[3] = ((char *)(void *)a)[3]; \ 193 ((char *)(void *)a)[0] = _tmp[3]; \ 194 ((char *)(void *)a)[1] = _tmp[2]; \ 195 ((char *)(void *)a)[2] = _tmp[1]; \ 196 ((char *)(void *)a)[3] = _tmp[0]; \ 197 } 198 #define P_32_COPY(a, b) { \ 199 ((char *)(void *)&(b))[0] = ((char *)(void *)&(a))[3]; \ 200 ((char *)(void *)&(b))[1] = ((char *)(void *)&(a))[2]; \ 201 ((char *)(void *)&(b))[2] = ((char *)(void *)&(a))[1]; \ 202 ((char *)(void *)&(b))[3] = ((char *)(void *)&(a))[0]; \ 203 } 204 205 /* 206 * Little endian <==> big endian 16-bit swap macros. 207 * M_16_SWAP swap a memory location 208 * P_16_SWAP swap a referenced memory location 209 * P_16_COPY swap from one location to another 210 */ 211 #define M_16_SWAP(a) { \ 212 uint16_t _tmp = a; \ 213 ((char *)(void *)&a)[0] = ((char *)(void *)&_tmp)[1]; \ 214 ((char *)(void *)&a)[1] = ((char *)(void *)&_tmp)[0]; \ 215 } 216 #define P_16_SWAP(a) { \ 217 char _tmp[2]; \ 218 _tmp[0] = ((char *)(void *)a)[0]; \ 219 _tmp[1] = ((char *)(void *)a)[1]; \ 220 ((char *)(void *)a)[0] = _tmp[1]; \ 221 ((char *)(void *)a)[1] = _tmp[0]; \ 222 } 223 #define P_16_COPY(a, b) { \ 224 ((char *)(void *)&(b))[0] = ((char *)(void *)&(a))[1]; \ 225 ((char *)(void *)&(b))[1] = ((char *)(void *)&(a))[0]; \ 226 } 227 #endif 228 229 __BEGIN_DECLS 230 DB *dbopen(const char *, int, mode_t, DBTYPE, const void *); 231 232 #ifdef __DBINTERFACE_PRIVATE 233 234 #define _DBFIT(a, t) _DIAGASSERT(__type_fit(t, a)) 235 236 DB *__bt_open(const char *, int, mode_t, const BTREEINFO *, int); 237 DB *__hash_open(const char *, int, mode_t, const HASHINFO *, int); 238 DB *__rec_open(const char *, int, mode_t, const RECNOINFO *, int); 239 void __dbpanic(DB *); 240 struct stat; 241 int __dbopen(const char *, int, mode_t, struct stat *); 242 int __dbtemp(const char *, struct stat *); 243 #endif 244 __END_DECLS 245 #endif /* !_DB_H_ */ 246