about summary refs log tree commit diff
path: root/db2/include/hash.h
blob: 5d85a2a3a788c66009d2049074668279652ac695 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
/*-
 * See the file LICENSE for redistribution information.
 *
 * Copyright (c) 1996, 1997, 1998
 *	Sleepycat Software.  All rights reserved.
 */
/*
 * Copyright (c) 1990, 1993, 1994
 *	Margo Seltzer.  All rights reserved.
 */
/*
 * Copyright (c) 1990, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Margo Seltzer.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)hash.h	10.14 (Sleepycat) 10/4/98
 */

/* Cursor structure definitions. */
typedef struct cursor_t {
	DBC		*dbc;

	/* Per-thread information */
	DB_LOCK hlock;			/* Metadata page lock. */
	HASHHDR *hdr;			/* Pointer to meta-data page. */
	PAGE *split_buf;		/* Temporary buffer for splits. */
	struct __db_h_stat stats;	/* Hash statistics. */

	/* Hash cursor information */
	db_pgno_t	bucket;		/* Bucket we are traversing. */
	db_pgno_t	lbucket;	/* Bucket for which we are locked. */
	DB_LOCK		lock;		/* Lock held on the current bucket. */
	PAGE		*pagep;		/* The current page. */
	db_pgno_t	pgno;		/* Current page number. */
	db_indx_t	bndx;		/* Index within the current page. */
	PAGE		*dpagep;	/* Duplicate page pointer. */
	db_pgno_t	dpgno;		/* Duplicate page number. */
	db_indx_t	dndx;		/* Index within a duplicate set. */
	db_indx_t	dup_off;	/* Offset within a duplicate set. */
	db_indx_t	dup_len;	/* Length of current duplicate. */
	db_indx_t	dup_tlen;	/* Total length of duplicate entry. */
	u_int32_t	seek_size;	/* Number of bytes we need for add. */
	db_pgno_t	seek_found_page;/* Page on which we can insert. */

#define	H_DELETED	0x0001		/* Cursor item is deleted. */
#define	H_DUPONLY	0x0002		/* Dups only; do not change key. */
#define	H_EXPAND	0x0004		/* Table expanded. */
#define	H_ISDUP		0x0008		/* Cursor is within duplicate set. */
#define	H_NOMORE	0x0010		/* No more entries in bucket. */
#define	H_OK		0x0020		/* Request succeeded. */
#define H_DIRTY		0x0040		/* Meta-data page needs to be written */
#define	H_ORIGINAL	0x0080		/* Bucket lock existed on entry. */
	u_int32_t	flags;
} HASH_CURSOR;

#define	IS_VALID(C) ((C)->bucket != BUCKET_INVALID)

#define	SAVE_CURSOR(ORIG, COPY) {					\
	F_SET((ORIG), H_ORIGINAL);					\
	*(COPY) = *(ORIG);						\
}

#define	RESTORE_CURSOR(D, ORIG, COPY, RET) {				\
	if ((RET) == 0) {						\
		if ((ORIG)->dbc->txn == NULL &&				\
		    (COPY)->lock != 0 && (ORIG)->lock != (COPY)->lock)	\
			(void)lock_put((D)->dbenv->lk_info, (COPY)->lock); \
	} else {							\
		if ((ORIG)->dbc->txn == NULL &&				\
		    (ORIG)->lock != 0 && (ORIG)->lock != (COPY)->lock)	\
			(void)lock_put((D)->dbenv->lk_info, (ORIG)->lock); \
		*ORIG = *COPY;						\
	}								\
}

/*
 * More interface macros used to get/release the meta data page.
 */
#define	GET_META(D, I, R) {						\
	if (F_ISSET(D, DB_AM_LOCKING) &&				\
	    !F_ISSET((I)->dbc, DBC_RECOVER)) {				\
		(I)->dbc->lock.pgno = BUCKET_INVALID;			\
		(R) = lock_get((D)->dbenv->lk_info, (I)->dbc->locker, 	\
		    0, &(I)->dbc->lock_dbt, DB_LOCK_READ, &(I)->hlock);	\
		(R) = (R) < 0 ? EAGAIN : (R);				\
	}								\
	if ((R) == 0 && 						\
	    ((R) = __ham_get_page(D, 0, (PAGE **)&((I)->hdr))) != 0 &&  \
	    (I)->hlock != LOCK_INVALID) {				\
		(void)lock_put((D)->dbenv->lk_info, (I)->hlock);	\
		(I)->hlock = LOCK_INVALID;				\
	}								\
}

#define	RELEASE_META(D, I) {						\
	if ((I)->hdr)							\
		(void)__ham_put_page(D, (PAGE *)(I)->hdr,		\
		    F_ISSET(I, H_DIRTY) ? 1 : 0);			\
	(I)->hdr = NULL;						\
	if (!F_ISSET((I)->dbc, DBC_RECOVER) &&				\
	    (I)->dbc->txn == NULL && (I)->hlock)			\
		(void)lock_put((D)->dbenv->lk_info, (I)->hlock);	\
	(I)->hlock = LOCK_INVALID;					\
	F_CLR(I, H_DIRTY);						\
}

#define	DIRTY_META(D, I, R) {						\
	if (F_ISSET(D, DB_AM_LOCKING) &&				\
	    !F_ISSET((I)->dbc, DBC_RECOVER)) {				\
		DB_LOCK _tmp;						\
		(I)->dbc->lock.pgno = BUCKET_INVALID;			\
	    	if (((R) = lock_get((D)->dbenv->lk_info,		\
	    	    (I)->dbc->locker, 0, &(I)->dbc->lock_dbt,		\
	    	    DB_LOCK_WRITE, &_tmp)) == 0)			\
			(R) = lock_put((D)->dbenv->lk_info, (I)->hlock);\
		else if ((R) < 0)					\
			(R) = EAGAIN;					\
		(I)->hlock = _tmp;					\
	}								\
	F_SET((I), H_DIRTY);						\
}

/* Test string. */
#define	CHARKEY			"%$sniglet^&"

/* Overflow management */
/*
 * Overflow page numbers are allocated per split point.  At each doubling of
 * the table, we can allocate extra pages.  We keep track of how many pages
 * we've allocated at each point to calculate bucket to page number mapping.
 */
#define	BUCKET_TO_PAGE(I, B) \
	((B) + 1 + ((B) ? (I)->hdr->spares[__db_log2((B)+1)-1] : 0))

#define	PGNO_OF(I, S, O) (BUCKET_TO_PAGE((I), (1 << (S)) - 1) + (O))

/* Constraints about number of pages and how much data goes on a page. */

#define	MAX_PAGES(H)	UINT32_T_MAX
#define	MINFILL		4
#define	ISBIG(I, N)	(((N) > ((I)->hdr->pagesize / MINFILL)) ? 1 : 0)

/* Shorthands for accessing structure */
#define	NDX_INVALID	0xFFFF
#define	BUCKET_INVALID	0xFFFFFFFF

/* On page duplicates are stored as a string of size-data-size triples. */
#define	DUP_SIZE(len)	((len) + 2 * sizeof(db_indx_t))

/* Log messages types (these are subtypes within a record type) */
#define	PAIR_KEYMASK		0x1
#define	PAIR_DATAMASK		0x2
#define	PAIR_ISKEYBIG(N)	(N & PAIR_KEYMASK)
#define	PAIR_ISDATABIG(N)	(N & PAIR_DATAMASK)
#define	OPCODE_OF(N)    	(N & ~(PAIR_KEYMASK | PAIR_DATAMASK))

#define	PUTPAIR		0x20
#define	DELPAIR		0x30
#define	PUTOVFL		0x40
#define	DELOVFL		0x50
#define	ALLOCPGNO	0x60
#define	DELPGNO		0x70
#define	SPLITOLD	0x80
#define	SPLITNEW	0x90

#include "hash_auto.h"
#include "hash_ext.h"
#include "db_am.h"
#include "common_ext.h"