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  * $FreeBSD: head/include/db.h 203964 2010-02-16 19:39:50Z imp $
  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 uint32_t        pgno_t;
  47 #define MAX_PAGE_OFFSET 65535           /* >= # of bytes in a page */
  48 typedef uint16_t        indx_t;
  49 #define MAX_REC_NUMBER  0xffffffff      /* >= # of records in a tree */
  50 typedef uint32_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 *, unsigned int);
 101         int (*get)(const struct __db *, const DBT *, DBT *, unsigned int);
 102         int (*put)(const struct __db *, DBT *, const DBT *, unsigned int);
 103         int (*seq)(const struct __db *, DBT *, DBT *, unsigned int);
 104         int (*sync)(const struct __db *, unsigned int);
 105         void *internal;                 /* Access method private. */
 106         int (*fd)(const struct __db *);
 107         void *mutex;
 108 } DB;
 109
 110 #define __DB_IS_THREADSAFE      1
 111
 112 #define BTREEMAGIC      0x053162
 113 #define BTREEVERSION    3
 114
 115 /* Structure used to pass parameters to the btree routines. */
 116 typedef struct {
 117 #define R_DUP           0x01    /* duplicate keys */
 118         unsigned long   flags;
 119         unsigned int    cachesize;      /* bytes to cache */
 120         int             maxkeypage;     /* maximum keys per page */
 121         int             minkeypage;     /* minimum keys per page */
 122         unsigned int    psize;          /* page size */
 123         int             (*compare)      /* comparison function */
 124                             (const DBT *, const DBT *);
 125         size_t          (*prefix)       /* prefix function */
 126                             (const DBT *, const DBT *);
 127         int             lorder;         /* byte order */
 128 } BTREEINFO;
 129
 130 #define HASHMAGIC       0x061561
 131 #define HASHVERSION     2
 132
 133 /* Structure used to pass parameters to the hashing routines. */
 134 typedef struct {
 135         unsigned int    bsize;          /* bucket size */
 136         unsigned int    ffactor;        /* fill factor */
 137         unsigned int    nelem;          /* number of elements */
 138         unsigned int    cachesize;      /* bytes to cache */
 139         uint32_t                        /* hash function */
 140                 (*hash)(const void *, size_t);
 141         int     lorder;         /* byte order */
 142 } HASHINFO;
 143
 144 /* Structure used to pass parameters to the record routines. */
 145 typedef struct {
 146 #define R_FIXEDLEN      0x01    /* fixed-length records */
 147 #define R_NOKEY         0x02    /* key not required */
 148 #define R_SNAPSHOT      0x04    /* snapshot the input */
 149         unsigned long   flags;
 150         unsigned int    cachesize; /* bytes to cache */
 151         unsigned int    psize;  /* page size */
 152         int             lorder; /* byte order */
 153         size_t          reclen; /* record length (fixed-length records) */
 154         unsigned char   bval;   /* delimiting byte (variable-length records */
 155         char    *bfname;        /* btree file name */
 156 } RECNOINFO;
 157
 158 #ifdef __DBINTERFACE_PRIVATE
 159 /*
 160  * Little endian <==> big endian 32-bit swap macros.
 161  *      M_32_SWAP       swap a memory location
 162  *      P_32_SWAP       swap a referenced memory location
 163  *      P_32_COPY       swap from one location to another
 164  */
 165 #define M_32_SWAP(a) {                                                  \
 166         uint32_t _tmp = a;                                              \
 167         ((char *)&a)[0] = ((char *)&_tmp)[3];                           \
 168         ((char *)&a)[1] = ((char *)&_tmp)[2];                           \
 169         ((char *)&a)[2] = ((char *)&_tmp)[1];                           \
 170         ((char *)&a)[3] = ((char *)&_tmp)[0];                           \
 171 }
 172 #define P_32_SWAP(a) {                                                  \
 173         uint32_t _tmp = *(uint32_t *)a;                                 \
 174         ((char *)a)[0] = ((char *)&_tmp)[3];                            \
 175         ((char *)a)[1] = ((char *)&_tmp)[2];                            \
 176         ((char *)a)[2] = ((char *)&_tmp)[1];                            \
 177         ((char *)a)[3] = ((char *)&_tmp)[0];                            \
 178 }
 179 #define P_32_COPY(a, b) {                                               \
 180         ((char *)&(b))[0] = ((char *)&(a))[3];                          \
 181         ((char *)&(b))[1] = ((char *)&(a))[2];                          \
 182         ((char *)&(b))[2] = ((char *)&(a))[1];                          \
 183         ((char *)&(b))[3] = ((char *)&(a))[0];                          \
 184 }
 185
 186 /*
 187  * Little endian <==> big endian 16-bit swap macros.
 188  *      M_16_SWAP       swap a memory location
 189  *      P_16_SWAP       swap a referenced memory location
 190  *      P_16_COPY       swap from one location to another
 191  */
 192 #define M_16_SWAP(a) {                                                  \
 193         uint16_t _tmp = a;                                              \
 194         ((char *)&a)[0] = ((char *)&_tmp)[1];                           \
 195         ((char *)&a)[1] = ((char *)&_tmp)[0];                           \
 196 }
 197 #define P_16_SWAP(a) {                                                  \
 198         uint16_t _tmp = *(uint16_t *)a;                                 \
 199         ((char *)a)[0] = ((char *)&_tmp)[1];                            \
 200         ((char *)a)[1] = ((char *)&_tmp)[0];                            \
 201 }
 202 #define P_16_COPY(a, b) {                                               \
 203         ((char *)&(b))[0] = ((char *)&(a))[1];                          \
 204         ((char *)&(b))[1] = ((char *)&(a))[0];                          \
 205 }
 206 #endif
 207
 208 __BEGIN_DECLS
 209 #if __BSD_VISIBLE
 210 DB *dbopen(const char *, int, mode_t, DBTYPE, const void *);
 211 #endif
 212
 213 #ifdef __DBINTERFACE_PRIVATE
 214 DB      *__bt_open(const char *, int, mode_t, const BTREEINFO *, int);
 215 DB      *__hash_open(const char *, int, mode_t, const HASHINFO *, int);
 216 DB      *__rec_open(const char *, int, mode_t, const RECNOINFO *, int);
 217 void     __dbpanic(DB *);
 218 #endif
 219 __END_DECLS
 220 #endif /* !_DB_H_ */