xref: /freebsd/include/db.h (revision 2a4a1db342263067035ce69a4017c645da63455d)
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  * $FreeBSD$
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 *, u_int);
105 	int (*get)(const struct __db *, const DBT *, DBT *, u_int);
106 	int (*put)(const struct __db *, DBT *, const DBT *, u_int);
107 	int (*seq)(const struct __db *, DBT *, DBT *, u_int);
108 	int (*sync)(const struct __db *, u_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 	u_long	flags;
120 	u_int	cachesize;	/* bytes to cache */
121 	int	maxkeypage;	/* maximum keys per page */
122 	int	minkeypage;	/* minimum keys per page */
123 	u_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 	u_int	bsize;		/* bucket size */
137 	u_int	ffactor;	/* fill factor */
138 	u_int	nelem;		/* number of elements */
139 	u_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 	u_long	flags;
151 	u_int	cachesize;	/* bytes to cache */
152 	u_int	psize;		/* page size */
153 	int	lorder;		/* byte order */
154 	size_t	reclen;		/* record length (fixed-length records) */
155 	u_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_ */
220