xref: /dragonfly/include/db.h (revision bd5862e7)
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_ */
221