xref: /freebsd/include/db.h (revision 1670a1c2a47d10ecccd001970b859caf93cd3b6e)
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  * $FreeBSD$
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 } 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 	unsigned long	flags;
116 	unsigned int	cachesize;	/* bytes to cache */
117 	int		maxkeypage;	/* maximum keys per page */
118 	int		minkeypage;	/* minimum keys per page */
119 	unsigned 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 	unsigned int	bsize;		/* bucket size */
133 	unsigned int	ffactor;	/* fill factor */
134 	unsigned int	nelem;		/* number of elements */
135 	unsigned int	cachesize;	/* bytes to cache */
136 	uint32_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 	unsigned long	flags;
147 	unsigned int	cachesize; /* bytes to cache */
148 	unsigned int	psize;	/* page size */
149 	int		lorder;	/* byte order */
150 	size_t		reclen;	/* record length (fixed-length records) */
151 	unsigned 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 	uint32_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 	uint32_t _tmp = *(uint32_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 	uint16_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 	uint16_t _tmp = *(uint16_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 #if __BSD_VISIBLE
207 DB *dbopen(const char *, int, int, DBTYPE, const void *);
208 #endif
209 
210 #ifdef __DBINTERFACE_PRIVATE
211 DB	*__bt_open(const char *, int, int, const BTREEINFO *, int);
212 DB	*__hash_open(const char *, int, int, const HASHINFO *, int);
213 DB	*__rec_open(const char *, int, int, const RECNOINFO *, int);
214 void	 __dbpanic(DB *dbp);
215 #endif
216 __END_DECLS
217 #endif /* !_DB_H_ */
218