include/db.h

   1 /*-
   2  * Copyright (c) 1990, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. All advertising materials mentioning features or use of this software
  14  *    must display the following acknowledgement:
  15  *      This product includes software developed by the University of
  16  *      California, Berkeley and its contributors.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)db.h        8.7 (Berkeley) 6/16/94
  34  * $FreeBSD: src/include/db.h,v 1.5 2002/03/26 01:35:05 bde Exp $
  35  */
  36
  37 #ifndef _DB_H_
  38 #define _DB_H_
  39
  40 #include <sys/types.h>
  41 #include <sys/cdefs.h>
  42
  43 #include <limits.h>
  44
  45 #define RET_ERROR       -1              /* Return values. */
  46 #define RET_SUCCESS      0
  47 #define RET_SPECIAL      1
  48
  49 #define MAX_PAGE_NUMBER 0xffffffff      /* >= # of pages in a file */
  50 typedef u_int32_t       pgno_t;
  51 #define MAX_PAGE_OFFSET 65535           /* >= # of bytes in a page */
  52 typedef u_int16_t       indx_t;
  53 #define MAX_REC_NUMBER  0xffffffff      /* >= # of records in a tree */
  54 typedef u_int32_t       recno_t;
  55
  56 /* Key/data structure -- a Data-Base Thang. */
  57 typedef struct {
  58         void    *data;                  /* data */
  59         size_t   size;                  /* data length */
  60 } DBT;
  61
  62 /* Routine flags. */
  63 #define R_CURSOR        1               /* del, put, seq */
  64 #define __R_UNUSED      2               /* UNUSED */
  65 #define R_FIRST         3               /* seq */
  66 #define R_IAFTER        4               /* put (RECNO) */
  67 #define R_IBEFORE       5               /* put (RECNO) */
  68 #define R_LAST          6               /* seq (BTREE, RECNO) */
  69 #define R_NEXT          7               /* seq */
  70 #define R_NOOVERWRITE   8               /* put */
  71 #define R_PREV          9               /* seq (BTREE, RECNO) */
  72 #define R_SETCURSOR     10              /* put (RECNO) */
  73 #define R_RECNOSYNC     11              /* sync (RECNO) */
  74
  75 typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE;
  76
  77 /*
  78  * !!!
  79  * The following flags are included in the dbopen(3) call as part of the
  80  * open(2) flags.  In order to avoid conflicts with the open flags, start
  81  * at the top of the 16 or 32-bit number space and work our way down.  If
  82  * the open flags were significantly expanded in the future, it could be
  83  * a problem.  Wish I'd left another flags word in the dbopen call.
  84  *
  85  * !!!
  86  * None of this stuff is implemented yet.  The only reason that it's here
  87  * is so that the access methods can skip copying the key/data pair when
  88  * the DB_LOCK flag isn't set.
  89  */
  90 #if UINT_MAX > 65535
  91 #define DB_LOCK         0x20000000      /* Do locking. */
  92 #define DB_SHMEM        0x40000000      /* Use shared memory. */
  93 #define DB_TXN          0x80000000      /* Do transactions. */
  94 #else
  95 #define DB_LOCK             0x2000      /* Do locking. */
  96 #define DB_SHMEM            0x4000      /* Use shared memory. */
  97 #define DB_TXN              0x8000      /* Do transactions. */
  98 #endif
  99
 100 /* Access method description structure. */
 101 typedef struct __db {
 102         DBTYPE type;                    /* Underlying db type. */
 103         int (*close)(struct __db *);
 104         int (*del)(const struct __db *, const DBT *, unsigned int);
 105         int (*get)(const struct __db *, const DBT *, DBT *, unsigned int);
 106         int (*put)(const struct __db *, DBT *, const DBT *, unsigned int);
 107         int (*seq)(const struct __db *, DBT *, DBT *, unsigned int);
 108         int (*sync)(const struct __db *, unsigned int);
 109         void *internal;                 /* Access method private. */
 110         int (*fd)(const struct __db *);
 111 } DB;
 112
 113 #define BTREEMAGIC      0x053162
 114 #define BTREEVERSION    3
 115
 116 /* Structure used to pass parameters to the btree routines. */
 117 typedef struct {
 118 #define R_DUP           0x01    /* duplicate keys */
 119         unsigned long   flags;
 120         unsigned int    cachesize;      /* bytes to cache */
 121         int             maxkeypage;     /* maximum keys per page */
 122         int             minkeypage;     /* minimum keys per page */
 123         unsigned int    psize;          /* page size */
 124         int             (*compare)      /* comparison function */
 125                         (const DBT *, const DBT *);
 126         size_t          (*prefix)       /* prefix function */
 127                         (const DBT *, const DBT *);
 128         int             lorder;         /* byte order */
 129 } BTREEINFO;
 130
 131 #define HASHMAGIC       0x061561
 132 #define HASHVERSION     2
 133
 134 /* Structure used to pass parameters to the hashing routines. */
 135 typedef struct {
 136         unsigned int    bsize;          /* bucket size */
 137         unsigned int    ffactor;        /* fill factor */
 138         unsigned int    nelem;          /* number of elements */
 139         unsigned int    cachesize;      /* bytes to cache */
 140         u_int32_t               /* hash function */
 141                 (*hash)(const void *, size_t);
 142         int     lorder;         /* byte order */
 143 } HASHINFO;
 144
 145 /* Structure used to pass parameters to the record routines. */
 146 typedef struct {
 147 #define R_FIXEDLEN      0x01    /* fixed-length records */
 148 #define R_NOKEY         0x02    /* key not required */
 149 #define R_SNAPSHOT      0x04    /* snapshot the input */
 150         unsigned long   flags;
 151         unsigned int    cachesize;      /* bytes to cache */
 152         unsigned int    psize;          /* page size */
 153         int             lorder;         /* byte order */
 154         size_t          reclen;         /* record length (fixed-length records) */
 155         unsigned char   bval;           /* delimiting byte (variable-length records */
 156         char    *bfname;        /* btree file name */
 157 } RECNOINFO;
 158
 159 #ifdef __DBINTERFACE_PRIVATE
 160 /*
 161  * Little endian <==> big endian 32-bit swap macros.
 162  *      M_32_SWAP       swap a memory location
 163  *      P_32_SWAP       swap a referenced memory location
 164  *      P_32_COPY       swap from one location to another
 165  */
 166 #define M_32_SWAP(a) {                                                  \
 167         u_int32_t _tmp = a;                                             \
 168         ((char *)&a)[0] = ((char *)&_tmp)[3];                           \
 169         ((char *)&a)[1] = ((char *)&_tmp)[2];                           \
 170         ((char *)&a)[2] = ((char *)&_tmp)[1];                           \
 171         ((char *)&a)[3] = ((char *)&_tmp)[0];                           \
 172 }
 173 #define P_32_SWAP(a) {                                                  \
 174         u_int32_t _tmp = *(u_int32_t *)a;                               \
 175         ((char *)a)[0] = ((char *)&_tmp)[3];                            \
 176         ((char *)a)[1] = ((char *)&_tmp)[2];                            \
 177         ((char *)a)[2] = ((char *)&_tmp)[1];                            \
 178         ((char *)a)[3] = ((char *)&_tmp)[0];                            \
 179 }
 180 #define P_32_COPY(a, b) {                                               \
 181         ((char *)&(b))[0] = ((char *)&(a))[3];                          \
 182         ((char *)&(b))[1] = ((char *)&(a))[2];                          \
 183         ((char *)&(b))[2] = ((char *)&(a))[1];                          \
 184         ((char *)&(b))[3] = ((char *)&(a))[0];                          \
 185 }
 186
 187 /*
 188  * Little endian <==> big endian 16-bit swap macros.
 189  *      M_16_SWAP       swap a memory location
 190  *      P_16_SWAP       swap a referenced memory location
 191  *      P_16_COPY       swap from one location to another
 192  */
 193 #define M_16_SWAP(a) {                                                  \
 194         u_int16_t _tmp = a;                                             \
 195         ((char *)&a)[0] = ((char *)&_tmp)[1];                           \
 196         ((char *)&a)[1] = ((char *)&_tmp)[0];                           \
 197 }
 198 #define P_16_SWAP(a) {                                                  \
 199         u_int16_t _tmp = *(u_int16_t *)a;                               \
 200         ((char *)a)[0] = ((char *)&_tmp)[1];                            \
 201         ((char *)a)[1] = ((char *)&_tmp)[0];                            \
 202 }
 203 #define P_16_COPY(a, b) {                                               \
 204         ((char *)&(b))[0] = ((char *)&(a))[1];                          \
 205         ((char *)&(b))[1] = ((char *)&(a))[0];                          \
 206 }
 207 #endif
 208
 209 __BEGIN_DECLS
 210 DB *dbopen(const char *, int, int, DBTYPE, const void *);
 211
 212 #ifdef __DBINTERFACE_PRIVATE
 213 DB      *__bt_open(const char *, int, int, const BTREEINFO *, int);
 214 DB      *__hash_open(const char *, int, int, const HASHINFO *, int);
 215 DB      *__rec_open(const char *, int, int, const RECNOINFO *, int);
 216 void     __dbpanic(DB *dbp);
 217 #endif
 218 __END_DECLS
 219 #endif /* !_DB_H_ */