xref: /illumos-gate/usr/src/cmd/sendmail/db/include/hash.h (revision 7c478bd9)
1 /*-
2  * See the file LICENSE for redistribution information.
3  *
4  * Copyright (c) 1996, 1997, 1998
5  *	Sleepycat Software.  All rights reserved.
6  */
7 /*
8  * Copyright (c) 1990, 1993, 1994
9  *	Margo Seltzer.  All rights reserved.
10  */
11 /*
12  * Copyright (c) 1990, 1993, 1994
13  *	The Regents of the University of California.  All rights reserved.
14  *
15  * This code is derived from software contributed to Berkeley by
16  * Margo Seltzer.
17  *
18  * Redistribution and use in source and binary forms, with or without
19  * modification, are permitted provided that the following conditions
20  * are met:
21  * 1. Redistributions of source code must retain the above copyright
22  *    notice, this list of conditions and the following disclaimer.
23  * 2. Redistributions in binary form must reproduce the above copyright
24  *    notice, this list of conditions and the following disclaimer in the
25  *    documentation and/or other materials provided with the distribution.
26  * 3. All advertising materials mentioning features or use of this software
27  *    must display the following acknowledgement:
28  *	This product includes software developed by the University of
29  *	California, Berkeley and its contributors.
30  * 4. Neither the name of the University nor the names of its contributors
31  *    may be used to endorse or promote products derived from this software
32  *    without specific prior written permission.
33  *
34  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
35  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
36  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
37  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
38  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
39  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
40  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
41  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
42  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
43  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
44  * SUCH DAMAGE.
45  *
46  *	@(#)hash.h	10.14 (Sleepycat) 10/4/98
47  */
48 
49 /* Cursor structure definitions. */
50 typedef struct cursor_t {
51 	DBC		*dbc;
52 
53 	/* Per-thread information */
54 	DB_LOCK hlock;			/* Metadata page lock. */
55 	HASHHDR *hdr;			/* Pointer to meta-data page. */
56 	PAGE *split_buf;		/* Temporary buffer for splits. */
57 	struct __db_h_stat stats;	/* Hash statistics. */
58 
59 	/* Hash cursor information */
60 	db_pgno_t	bucket;		/* Bucket we are traversing. */
61 	db_pgno_t	lbucket;	/* Bucket for which we are locked. */
62 	DB_LOCK		lock;		/* Lock held on the current bucket. */
63 	PAGE		*pagep;		/* The current page. */
64 	db_pgno_t	pgno;		/* Current page number. */
65 	db_indx_t	bndx;		/* Index within the current page. */
66 	PAGE		*dpagep;	/* Duplicate page pointer. */
67 	db_pgno_t	dpgno;		/* Duplicate page number. */
68 	db_indx_t	dndx;		/* Index within a duplicate set. */
69 	db_indx_t	dup_off;	/* Offset within a duplicate set. */
70 	db_indx_t	dup_len;	/* Length of current duplicate. */
71 	db_indx_t	dup_tlen;	/* Total length of duplicate entry. */
72 	u_int32_t	seek_size;	/* Number of bytes we need for add. */
73 	db_pgno_t	seek_found_page;/* Page on which we can insert. */
74 
75 #define	H_DELETED	0x0001		/* Cursor item is deleted. */
76 #define	H_DUPONLY	0x0002		/* Dups only; do not change key. */
77 #define	H_EXPAND	0x0004		/* Table expanded. */
78 #define	H_ISDUP		0x0008		/* Cursor is within duplicate set. */
79 #define	H_NOMORE	0x0010		/* No more entries in bucket. */
80 #define	H_OK		0x0020		/* Request succeeded. */
81 #define H_DIRTY		0x0040		/* Meta-data page needs to be written */
82 #define	H_ORIGINAL	0x0080		/* Bucket lock existed on entry. */
83 	u_int32_t	flags;
84 } HASH_CURSOR;
85 
86 #define	IS_VALID(C) ((C)->bucket != BUCKET_INVALID)
87 
88 #define	SAVE_CURSOR(ORIG, COPY) {					\
89 	F_SET((ORIG), H_ORIGINAL);					\
90 	*(COPY) = *(ORIG);						\
91 }
92 
93 #define	RESTORE_CURSOR(D, ORIG, COPY, RET) {				\
94 	if ((RET) == 0) {						\
95 		if ((ORIG)->dbc->txn == NULL &&				\
96 		    (COPY)->lock != 0 && (ORIG)->lock != (COPY)->lock)	\
97 			(void)lock_put((D)->dbenv->lk_info, (COPY)->lock); \
98 	} else {							\
99 		if ((ORIG)->dbc->txn == NULL &&				\
100 		    (ORIG)->lock != 0 && (ORIG)->lock != (COPY)->lock)	\
101 			(void)lock_put((D)->dbenv->lk_info, (ORIG)->lock); \
102 		*ORIG = *COPY;						\
103 	}								\
104 }
105 
106 /*
107  * More interface macros used to get/release the meta data page.
108  */
109 #define	GET_META(D, I, R) {						\
110 	if (F_ISSET(D, DB_AM_LOCKING) &&				\
111 	    !F_ISSET((I)->dbc, DBC_RECOVER)) {				\
112 		(I)->dbc->lock.pgno = BUCKET_INVALID;			\
113 		(R) = lock_get((D)->dbenv->lk_info, (I)->dbc->locker, 	\
114 		    0, &(I)->dbc->lock_dbt, DB_LOCK_READ, &(I)->hlock);	\
115 		(R) = (R) < 0 ? EAGAIN : (R);				\
116 	}								\
117 	if ((R) == 0 && 						\
118 	    ((R) = __ham_get_page(D, 0, (PAGE **)&((I)->hdr))) != 0 &&  \
119 	    (I)->hlock != LOCK_INVALID) {				\
120 		(void)lock_put((D)->dbenv->lk_info, (I)->hlock);	\
121 		(I)->hlock = LOCK_INVALID;				\
122 	}								\
123 }
124 
125 #define	RELEASE_META(D, I) {						\
126 	if ((I)->hdr)							\
127 		(void)__ham_put_page(D, (PAGE *)(I)->hdr,		\
128 		    F_ISSET(I, H_DIRTY) ? 1 : 0);			\
129 	(I)->hdr = NULL;						\
130 	if (!F_ISSET((I)->dbc, DBC_RECOVER) &&				\
131 	    (I)->dbc->txn == NULL && (I)->hlock)			\
132 		(void)lock_put((D)->dbenv->lk_info, (I)->hlock);	\
133 	(I)->hlock = LOCK_INVALID;					\
134 	F_CLR(I, H_DIRTY);						\
135 }
136 
137 #define	DIRTY_META(D, I, R) {						\
138 	if (F_ISSET(D, DB_AM_LOCKING) &&				\
139 	    !F_ISSET((I)->dbc, DBC_RECOVER)) {				\
140 		DB_LOCK _tmp;						\
141 		(I)->dbc->lock.pgno = BUCKET_INVALID;			\
142 	    	if (((R) = lock_get((D)->dbenv->lk_info,		\
143 	    	    (I)->dbc->locker, 0, &(I)->dbc->lock_dbt,		\
144 	    	    DB_LOCK_WRITE, &_tmp)) == 0)			\
145 			(R) = lock_put((D)->dbenv->lk_info, (I)->hlock);\
146 		else if ((R) < 0)					\
147 			(R) = EAGAIN;					\
148 		(I)->hlock = _tmp;					\
149 	}								\
150 	F_SET((I), H_DIRTY);						\
151 }
152 
153 /* Test string. */
154 #define	CHARKEY			"%$sniglet^&"
155 
156 /* Overflow management */
157 /*
158  * Overflow page numbers are allocated per split point.  At each doubling of
159  * the table, we can allocate extra pages.  We keep track of how many pages
160  * we've allocated at each point to calculate bucket to page number mapping.
161  */
162 #define	BUCKET_TO_PAGE(I, B) \
163 	((B) + 1 + ((B) ? (I)->hdr->spares[__db_log2((B)+1)-1] : 0))
164 
165 #define	PGNO_OF(I, S, O) (BUCKET_TO_PAGE((I), (1 << (S)) - 1) + (O))
166 
167 /* Constraints about number of pages and how much data goes on a page. */
168 
169 #define	MAX_PAGES(H)	UINT32_T_MAX
170 #define	MINFILL		4
171 #define	ISBIG(I, N)	(((N) > ((I)->hdr->pagesize / MINFILL)) ? 1 : 0)
172 
173 /* Shorthands for accessing structure */
174 #define	NDX_INVALID	0xFFFF
175 #define	BUCKET_INVALID	0xFFFFFFFF
176 
177 /* On page duplicates are stored as a string of size-data-size triples. */
178 #define	DUP_SIZE(len)	((len) + 2 * sizeof(db_indx_t))
179 
180 /* Log messages types (these are subtypes within a record type) */
181 #define	PAIR_KEYMASK		0x1
182 #define	PAIR_DATAMASK		0x2
183 #define	PAIR_ISKEYBIG(N)	(N & PAIR_KEYMASK)
184 #define	PAIR_ISDATABIG(N)	(N & PAIR_DATAMASK)
185 #define	OPCODE_OF(N)    	(N & ~(PAIR_KEYMASK | PAIR_DATAMASK))
186 
187 #define	PUTPAIR		0x20
188 #define	DELPAIR		0x30
189 #define	PUTOVFL		0x40
190 #define	DELOVFL		0x50
191 #define	ALLOCPGNO	0x60
192 #define	DELPGNO		0x70
193 #define	SPLITOLD	0x80
194 #define	SPLITNEW	0x90
195 
196 #include "hash_auto.h"
197 #include "hash_ext.h"
198 #include "db_am.h"
199 #include "common_ext.h"
200