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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  *      @(#)db.h        8.7 (Berkeley) 6/16/94
  30  * $DragonFly: src/include/db.h,v 1.4 2005/09/19 09:05:31 asmodai Exp $
  31  */
  32
  33 #ifndef _DB_H_
  34 #define _DB_H_
  35
  36 #include <sys/types.h>
  37 #include <sys/cdefs.h>
  38
  39 #include <limits.h>
  40
  41 #define RET_ERROR       -1              /* Return values. */
  42 #define RET_SUCCESS      0
  43 #define RET_SPECIAL      1
  44
  45 #define MAX_PAGE_NUMBER 0xffffffff      /* >= # of pages in a file */
  46 typedef u_int32_t       pgno_t;
  47 #define MAX_PAGE_OFFSET 65535           /* >= # of bytes in a page */
  48 typedef u_int16_t       indx_t;
  49 #define MAX_REC_NUMBER  0xffffffff      /* >= # of records in a tree */
  50 typedef u_int32_t       recno_t;
  51
  52 /* Key/data structure -- a Data-Base Thang. */
  53 typedef struct {
  54         void    *data;                  /* data */
  55         size_t   size;                  /* data length */
  56 } DBT;
  57
  58 /* Routine flags. */
  59 #define R_CURSOR        1               /* del, put, seq */
  60 #define __R_UNUSED      2               /* UNUSED */
  61 #define R_FIRST         3               /* seq */
  62 #define R_IAFTER        4               /* put (RECNO) */
  63 #define R_IBEFORE       5               /* put (RECNO) */
  64 #define R_LAST          6               /* seq (BTREE, RECNO) */
  65 #define R_NEXT          7               /* seq */
  66 #define R_NOOVERWRITE   8               /* put */
  67 #define R_PREV          9               /* seq (BTREE, RECNO) */
  68 #define R_SETCURSOR     10              /* put (RECNO) */
  69 #define R_RECNOSYNC     11              /* sync (RECNO) */
  70
  71 typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE;
  72
  73 /*
  74  * !!!
  75  * The following flags are included in the dbopen(3) call as part of the
  76  * open(2) flags.  In order to avoid conflicts with the open flags, start
  77  * at the top of the 16 or 32-bit number space and work our way down.  If
  78  * the open flags were significantly expanded in the future, it could be
  79  * a problem.  Wish I'd left another flags word in the dbopen call.
  80  *
  81  * !!!
  82  * None of this stuff is implemented yet.  The only reason that it's here
  83  * is so that the access methods can skip copying the key/data pair when
  84  * the DB_LOCK flag isn't set.
  85  */
  86 #if UINT_MAX > 65535
  87 #define DB_LOCK         0x20000000      /* Do locking. */
  88 #define DB_SHMEM        0x40000000      /* Use shared memory. */
  89 #define DB_TXN          0x80000000      /* Do transactions. */
  90 #else
  91 #define DB_LOCK             0x2000      /* Do locking. */
  92 #define DB_SHMEM            0x4000      /* Use shared memory. */
  93 #define DB_TXN              0x8000      /* Do transactions. */
  94 #endif
  95
  96 /* Access method description structure. */
  97 typedef struct __db {
  98         DBTYPE type;                    /* Underlying db type. */
  99         int (*close)    (struct __db *);
 100         int (*del)      (const struct __db *, const DBT *, u_int);
 101         int (*get)      (const struct __db *, const DBT *, DBT *, u_int);
 102         int (*put)      (const struct __db *, DBT *, const DBT *, u_int);
 103         int (*seq)      (const struct __db *, DBT *, DBT *, u_int);
 104         int (*sync)     (const struct __db *, u_int);
 105         void *internal;                 /* Access method private. */
 106         int (*fd)       (const struct __db *);
 107 } DB;
 108
 109 #define BTREEMAGIC      0x053162
 110 #define BTREEVERSION    3
 111
 112 /* Structure used to pass parameters to the btree routines. */
 113 typedef struct {
 114 #define R_DUP           0x01    /* duplicate keys */
 115         u_long  flags;
 116         u_int   cachesize;      /* bytes to cache */
 117         int     maxkeypage;     /* maximum keys per page */
 118         int     minkeypage;     /* minimum keys per page */
 119         u_int   psize;          /* page size */
 120         int     (*compare)      /* comparison function */
 121             (const DBT *, const DBT *);
 122         size_t  (*prefix)       /* prefix function */
 123             (const DBT *, const DBT *);
 124         int     lorder;         /* byte order */
 125 } BTREEINFO;
 126
 127 #define HASHMAGIC       0x061561
 128 #define HASHVERSION     2
 129
 130 /* Structure used to pass parameters to the hashing routines. */
 131 typedef struct {
 132         u_int   bsize;          /* bucket size */
 133         u_int   ffactor;        /* fill factor */
 134         u_int   nelem;          /* number of elements */
 135         u_int   cachesize;      /* bytes to cache */
 136         u_int32_t               /* hash function */
 137                 (*hash) (const void *, size_t);
 138         int     lorder;         /* byte order */
 139 } HASHINFO;
 140
 141 /* Structure used to pass parameters to the record routines. */
 142 typedef struct {
 143 #define R_FIXEDLEN      0x01    /* fixed-length records */
 144 #define R_NOKEY         0x02    /* key not required */
 145 #define R_SNAPSHOT      0x04    /* snapshot the input */
 146         u_long  flags;
 147         u_int   cachesize;      /* bytes to cache */
 148         u_int   psize;          /* page size */
 149         int     lorder;         /* byte order */
 150         size_t  reclen;         /* record length (fixed-length records) */
 151         u_char  bval;           /* delimiting byte (variable-length records) */
 152         char    *bfname;        /* btree file name */
 153 } RECNOINFO;
 154
 155 #ifdef __DBINTERFACE_PRIVATE
 156 /*
 157  * Little endian <==> big endian 32-bit swap macros.
 158  *      M_32_SWAP       swap a memory location
 159  *      P_32_SWAP       swap a referenced memory location
 160  *      P_32_COPY       swap from one location to another
 161  */
 162 #define M_32_SWAP(a) {                                                  \
 163         u_int32_t _tmp = a;                                             \
 164         ((char *)&a)[0] = ((char *)&_tmp)[3];                           \
 165         ((char *)&a)[1] = ((char *)&_tmp)[2];                           \
 166         ((char *)&a)[2] = ((char *)&_tmp)[1];                           \
 167         ((char *)&a)[3] = ((char *)&_tmp)[0];                           \
 168 }
 169 #define P_32_SWAP(a) {                                                  \
 170         u_int32_t _tmp = *(u_int32_t *)a;                               \
 171         ((char *)a)[0] = ((char *)&_tmp)[3];                            \
 172         ((char *)a)[1] = ((char *)&_tmp)[2];                            \
 173         ((char *)a)[2] = ((char *)&_tmp)[1];                            \
 174         ((char *)a)[3] = ((char *)&_tmp)[0];                            \
 175 }
 176 #define P_32_COPY(a, b) {                                               \
 177         ((char *)&(b))[0] = ((char *)&(a))[3];                          \
 178         ((char *)&(b))[1] = ((char *)&(a))[2];                          \
 179         ((char *)&(b))[2] = ((char *)&(a))[1];                          \
 180         ((char *)&(b))[3] = ((char *)&(a))[0];                          \
 181 }
 182
 183 /*
 184  * Little endian <==> big endian 16-bit swap macros.
 185  *      M_16_SWAP       swap a memory location
 186  *      P_16_SWAP       swap a referenced memory location
 187  *      P_16_COPY       swap from one location to another
 188  */
 189 #define M_16_SWAP(a) {                                                  \
 190         u_int16_t _tmp = a;                                             \
 191         ((char *)&a)[0] = ((char *)&_tmp)[1];                           \
 192         ((char *)&a)[1] = ((char *)&_tmp)[0];                           \
 193 }
 194 #define P_16_SWAP(a) {                                                  \
 195         u_int16_t _tmp = *(u_int16_t *)a;                               \
 196         ((char *)a)[0] = ((char *)&_tmp)[1];                            \
 197         ((char *)a)[1] = ((char *)&_tmp)[0];                            \
 198 }
 199 #define P_16_COPY(a, b) {                                               \
 200         ((char *)&(b))[0] = ((char *)&(a))[1];                          \
 201         ((char *)&(b))[1] = ((char *)&(a))[0];                          \
 202 }
 203 #endif
 204
 205 __BEGIN_DECLS
 206 DB *dbopen(const char *, int, mode_t, DBTYPE, const void *);
 207
 208 #ifdef __DBINTERFACE_PRIVATE
 209 DB      *__bt_open(const char *, int, int, const BTREEINFO *, int);
 210 DB      *__hash_open(const char *, int, int, const HASHINFO *, int);
 211 DB      *__rec_open(const char *, int, int, const RECNOINFO *, int);
 212 void     __dbpanic(DB *);
 213 #endif
 214 __END_DECLS
 215 #endif /* !_DB_H_ */