usr/src/include/db.h

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 *
 *      @(#)db.h        5.19 (Berkeley) %G%
 */

#ifndef _DB_H_
#define _DB_H_

#include <sys/types.h>
#include <sys/cdefs.h>

#define RET_ERROR       -1              /* Return values. */
#define RET_SUCCESS      0
#define RET_SPECIAL      1

#define MAX_PAGE_NUMBER ULONG_MAX       /* >= # of pages in a file */
typedef u_long  pgno_t;
#define MAX_PAGE_OFFSET USHRT_MAX       /* >= # of bytes in a page */
typedef u_short index_t;
#define MAX_REC_NUMBER  ULONG_MAX       /* >= # of records in a tree */
typedef u_long  recno_t;

/* Key/data structure -- a Data-Base Thang. */
typedef struct {
        void    *data;                  /* data */
        size_t   size;                  /* data length */
} DBT;

/* Routine flags. */
#define R_CURSOR        1               /* del, put, seq */
#define R_CURSORLOG     2               /* put (RECNO) */
#define R_FIRST         3               /* seq */
#define R_IAFTER        4               /* put (RECNO) */
#define R_IBEFORE       5               /* put (RECNO) */
#define R_LAST          6               /* seq (BTREE, RECNO) */
#define R_NEXT          7               /* seq */
#define R_NOOVERWRITE   8               /* put */
#define R_PREV          9               /* seq (BTREE, RECNO) */
#define R_SETCURSOR     10              /* put (RECNO) */

typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE;

/* Access method description structure. */
typedef struct __db {
        DBTYPE type;                    /* underlying db type */
        int (*close)    __P((struct __db *));
        int (*del)      __P((const struct __db *, const DBT *, u_int));
        int (*get)      __P((const struct __db *, const DBT *, DBT *, u_int));
        int (*put)      __P((const struct __db *, DBT *, const DBT *, u_int));
        int (*seq)      __P((const struct __db *, DBT *, DBT *, u_int));
        int (*sync)     __P((const struct __db *));
        void *internal;                 /* access method private */
} DB;

#define BTREEMAGIC      0x053162
#define BTREEVERSION    3

/* Structure used to pass parameters to the btree routines. */
typedef struct {
#define R_DUP           0x01    /* duplicate keys */
        u_long flags;
        int cachesize;          /* bytes to cache */
        int maxkeypage;         /* maximum keys per page */
        int minkeypage;         /* minimum keys per page */
        int psize;              /* page size */
                                /* comparison, prefix functions */
        int (*compare)  __P((const DBT *, const DBT *));
        int (*prefix)   __P((const DBT *, const DBT *));
        int lorder;             /* byte order */
} BTREEINFO;

#define HASHMAGIC       0x061561
#define HASHVERSION     2

/* Structure used to pass parameters to the hashing routines. */
typedef struct {
        int bsize;              /* bucket size */
        int ffactor;            /* fill factor */
        int nelem;              /* number of elements */
        int cachesize;          /* bytes to cache */
        int (*hash)();          /* hash function */
        int lorder;             /* byte order */
} HASHINFO;

/* Structure used to pass parameters to the record routines. */
typedef struct {
#define R_FIXEDLEN      0x01    /* fixed-length records */
#define R_NOKEY         0x02    /* key not required */
#define R_SNAPSHOT      0x04    /* snapshot the input */
        u_long flags;
        int cachesize;          /* bytes to cache */
        int lorder;             /* byte order */
        size_t reclen;          /* record length (fixed-length records) */
        u_char bval;            /* delimiting byte (variable-length records */
} RECNOINFO;

/* Key structure for the record routines. */
typedef struct {
        u_long number;
        u_long offset;
        u_long length;
#define R_LENGTH        0x01    /* length is valid */
#define R_NUMBER        0x02    /* record number is valid */
#define R_OFFSET        0x04    /* offset is valid */
        u_char valid;
} RECNOKEY;

/*
 * Little endian <==> big endian long swap macros.
 *      BLSWAP          swap a memory location
 *      BLPSWAP         swap a referenced memory location
 *      BLSWAP_COPY     swap from one location to another
 */
#define BLSWAP(a) { \
        u_long _tmp = a; \
        ((char *)&a)[0] = ((char *)&_tmp)[3]; \
        ((char *)&a)[1] = ((char *)&_tmp)[2]; \
        ((char *)&a)[2] = ((char *)&_tmp)[1]; \
        ((char *)&a)[3] = ((char *)&_tmp)[0]; \
}
#define BLPSWAP(a) { \
        u_long _tmp = *(u_long *)a; \
        ((char *)a)[0] = ((char *)&_tmp)[3]; \
        ((char *)a)[1] = ((char *)&_tmp)[2]; \
        ((char *)a)[2] = ((char *)&_tmp)[1]; \
        ((char *)a)[3] = ((char *)&_tmp)[0]; \
}
#define BLSWAP_COPY(a, b) { \
        ((char *)&(b))[0] = ((char *)&(a))[3]; \
        ((char *)&(b))[1] = ((char *)&(a))[2]; \
        ((char *)&(b))[2] = ((char *)&(a))[1]; \
        ((char *)&(b))[3] = ((char *)&(a))[0]; \
}

/*
 * Little endian <==> big endian short swap macros.
 *      BSSWAP          swap a memory location
 *      BSPSWAP         swap a referenced memory location
 *      BSSWAP_COPY     swap from one location to another
 */
#define BSSWAP(a) { \
        u_short _tmp = a; \
        ((char *)&a)[0] = ((char *)&_tmp)[1]; \
        ((char *)&a)[1] = ((char *)&_tmp)[0]; \
}
#define BSPSWAP(a) { \
        u_short _tmp = *(u_short *)a; \
        ((char *)a)[0] = ((char *)&_tmp)[1]; \
        ((char *)a)[1] = ((char *)&_tmp)[0]; \
}
#define BSSWAP_COPY(a, b) { \
        ((char *)&(b))[0] = ((char *)&(a))[1]; \
        ((char *)&(b))[1] = ((char *)&(a))[0]; \
}

__BEGIN_DECLS
DB *dbopen __P((const char *, int, int, DBTYPE, const void *));

#ifdef __DBINTERFACE_PRIVATE
DB      *__bt_open __P((const char *, int, int, const BTREEINFO *));
DB      *__hash_open __P((const char *, int, int, const HASHINFO *));
DB      *__rec_open __P((const char *, int, int, const RECNOINFO *));
void     __dbpanic __P((DB *dbp));
#endif
__END_DECLS
#endif /* !_DB_H_ */